答:
This issue was previously reported a as bug:

https://netbeans.org/bugzilla/show_bug.cgi?id=270350

but this error is caused by unicode characters like "\u00b3"

This issues were closed and fixed in the last version:

https://github.com/javaparser/javaparser/issues/1159
https://github.com/javaparser/javaparser/issues/404
https://github.com/javaparser/javaparser/pull/411

Upgrade to the latest version!

Title: Gradle Build failed for the task "processBasicDebugResources" error: com.github.javaparser.TokenMgrError


来源: stackexchange

问:
have classes in separte files access it's other c++
Well I have 2 classes in 2 header and 2 cpp files

```<code>#class1.h
#ifndef class1_h
#define class1_h
class myclass;
#endif

#class2.h
#ifndef class2_h
#define class2_h
class anotherclass;
#endif

#class1.cpp

class myclass
{
    anotherclass test1;
}

#class2.cpp

class anotherclass
{
    myclass test2;
}
</code>```

And of course a simple main
Well I think it's obvious why this thing wont even compile
my question here is how to make it compile?

Having the classes in different files is mandatory..

答: Header files define class interfaces.  Source code '.cpp' files are using for the implementation.  Your source code has the implementation and the class interface.</p>

ContentLicense: CC BY-SA 3.0

Body:
Well I have 2 classes in 2 header and 2 cpp files

#class1.h
#ifndef class1_h
#define class1_h
class myclass;
#endif

#class2.h
#ifndef class2_h
#define class2_h
class anotherclass;
#endif

#class1.cpp

class myclass
{
    anotherclass test1;
}

#class2.cpp

class anotherclass
{
    myclass test2;
}

And of course a simple main
Well I think it's obvious why this thing wont even compile
my question here is how to make it compile?

Having the classes in different files is mandatory..


问:
Read data from serial port in FreeRTOS
We have a issue during reading data from serial port. The C function which is used to read data have a argument for the data size in bytes. In order to read data  we need to know in advance the size of the incoming data. We use RFID reader via serial port connection. Data is send to Nucleo board in different size each time.
The other problem that we face is the Nucleo interruption during reading data. When we receive the data in height speed we need to initiate it again. This leads to data loss in height data transfer speeds.
One possible solution will be to use DMA(direct memory access) but we are not familiar wit this approach.
Can you propose some solution?</p>

答: I find your question confusing as you don't clearly state what the issue you are having is and you make assumptions that others will know how the functions you are calling are implemented.  In any case is sounds unrelated to FreeRTOS.</p>

Title: Read data from serial port in FreeRTOS


问:
I can't transfer my class variable into another class
Really desperate to ask this. I need to transfer my CipherText into another class, and it doesn't work. What am I missing? Sorry for the long post. (I've already removed the some GUI(tkinter) codes in those 2 class.) I can't seem to find solutions here. Would Gladly appreciate for some help. Thanks!!!

```<code>class Decmesbuttons():

   def decmescommand(self):
       datenow = str(datetime.datetime.now().date())
       timenow = str(datetime.datetime.now().time())

       privk = privkeyvarS.get()

       #No key found error
       try:
           pathpriv = r'/home/gene/Desktop/ppl/keys/' + privk
           loadprivkey = M2Crypto.RSA.load_key (pathpriv + '/' + privk + '-private.key')

       except IOError:
           tkMessageBox.showwarning("Warning!", "No "+ privk + " key found.")

       #Wrong key error & printing of the decrypted message
       try:
           PlainText = loadprivkey.private_decrypt (Ciphertext, M2Crypto.RSA.pkcs1_oaep_padding)

           if PlainText != "":
               tkMessageBox.showinfo("DECRYPTED!","Message decrypted by " + privk + " :" + Plaintext)

       except:
           tkMessageBox.showwarning("Warning!", "Wrong key!")

class Encmesbuttons():

    def encmescommand(self):
        datenow = str(datetime.datetime.now().date())
        timenow = str(datetime.datetime.now().time())

        m = messagevarS.get()
        pk = pubkeyvarS.get()

        #Input of selected message to encrypt

        em = m + '\n' + '-'
        if not m:
            tkMessageBox.showwarning("Warning!", "No message to encrypt")

        else:
            #add to log
            logkey = open ('log'+datenow+'.txt', 'a')
            logkey.write(timenow +'-'  + ' Some user inputted a message.' + "\n")
            logkey.close()

            f = open ('message.txt', 'w')
            f.write(str(m))
            f.close()

        try:
            #select the public key owner to send your encrypted message

            pathpub = r'/home/gene/Desktop/ppl/keys/' + pk
            loadpub = M2Crypto.RSA.load_pub_key (pathpub+ '/' + pk + '-public.key')

            global CT
            CipherText = loadpub.public_encrypt (m, M2Crypto.RSA.pkcs1_oaep_padding)
            CT = CipherText

            #Print the ciphered message

            tkMessageBox.showinfo("The encrypted message",str(CipherText.encode('base64')))

            #write ciphered text to file
            f = open ('encryption.txt', 'w')
            f.write(str(CipherText.encode ('base64')))
            f.close()

            #add to log
            logkey = open ('log'+datenow+'.txt', 'a')
            logkey.write(timenow +'-' + 'Some user has encrypted the message and selected ' + pk + ' as the receiver' +  "\n")
            logkey.close()

        except IOError:
            tkMessageBox.showwarning("Warning!", "No public key inputted")
</code>```

I need this variable:

```<code>CipherText = loadpub.public_encrypt (m, M2Crypto.RSA.pkcs1_oaep_padding)
</code>```

to be in this line (the one with the Here sign):

```<code> PlainText = loadprivkey.private_decrypt (**HERE**, M2Crypto.RSA.pkcs1_oaep_padding)
</code>```

答: The problem is your scoping.  You have CipherText defined inside a method.  Try taking out CipherText and making it a global variable in your class.  Then you will be able to access it by calling Encmesbuttons.CipherText.

Body:
Really desperate to ask this. I need to transfer my CipherText into another class, and it doesn't work. What am I missing? Sorry for the long post. (I've already removed the some GUI(tkinter) codes in those 2 class.) I can't seem to find solutions here. Would Gladly appreciate for some help. Thanks!!!

class Decmesbuttons():

   def decmescommand(self):
       datenow = str(datetime.datetime.now().date())
       timenow = str(datetime.datetime.now().time())

       privk = privkeyvarS.get()

       #No key found error
       try:
           pathpriv = r'/home/gene/Desktop/ppl/keys/' + privk
           loadprivkey = M2Crypto.RSA.load_key (pathpriv + '/' + privk + '-private.key')

       except IOError:
           tkMessageBox.showwarning("Warning!", "No "+ privk + " key found.")

       #Wrong key error & printing of the decrypted message
       try:
           PlainText = loadprivkey.private_decrypt (Ciphertext, M2Crypto.RSA.pkcs1_oaep_padding)

           if PlainText != "":
               tkMessageBox.showinfo("DECRYPTED!","Message decrypted by " + privk + " :" + Plaintext)

       except:
           tkMessageBox.showwarning("Warning!", "Wrong key!")

class Encmesbuttons():

    def encmescommand(self):
        datenow = str(datetime.datetime.now().date())
        timenow = str(datetime.datetime.now().time())

        m = messagevarS.get()
        pk = pubkeyvarS.get()

        #Input of selected message to encrypt

        em = m + '\n' + '-'
        if not m:
            tkMessageBox.showwarning("Warning!", "No message to encrypt")

        else:
            #add to log
            logkey = open ('log'+datenow+'.txt', 'a')
            logkey.write(timenow +'-'  + ' Some user inputted a message.' + "\n")
            logkey.close()

            f = open ('message.txt', 'w')
            f.write(str(m))
            f.close()

        try:
            #select the public key owner to send your encrypted message

            pathpub = r'/home/gene/Desktop/ppl/keys/' + pk
            loadpub = M2Crypto.RSA.load_pub_key (pathpub+ '/' + pk + '-public.key')

            global CT
            CipherText = loadpub.public_encrypt (m, M2Crypto.RSA.pkcs1_oaep_padding)
            CT = CipherText

            #Print the ciphered message

            tkMessageBox.showinfo("The encrypted message",str(CipherText.encode('base64')))

            #write ciphered text to file
            f = open ('encryption.txt', 'w')
            f.write(str(CipherText.encode ('base64')))
            f.close()

            #add to log
            logkey = open ('log'+datenow+'.txt', 'a')
            logkey.write(timenow +'-' + 'Some user has encrypted the message and selected ' + pk + ' as the receiver' +  "\n")
            logkey.close()

        except IOError:
            tkMessageBox.showwarning("Warning!", "No public key inputted")

I need this variable:

CipherText = loadpub.public_encrypt (m, M2Crypto.RSA.pkcs1_oaep_padding)

to be in this line (the one with the Here sign):

 PlainText = loadprivkey.private_decrypt (**HERE**, M2Crypto.RSA.pkcs1_oaep_padding)


问:
tkinter gui which loads a flie and can print out the file name
I am starting with python and I already created a nice plotting function with matplotlib. Now I want to insert the function into a GUI using tkinter.
As I learned from youtube and this forum I should use classes.
Unfortunately I have some problems with that. What I have so far (where I do not understand everything in detail) is:

```<code>import tkinter as tk
from tkinter import filedialog

LARGE_FONT=('Verdana',12)

class XPSPlotApp(tk.Tk):

    def __init__(self, *args,**kwargs):
        tk.Tk.__init__(self, *args,**kwargs)
        container=tk.Frame(self)

        container.pack(side='top',fill='both',expand=True)
        container.grid_rowconfigure(0,weight=1)#0 is min size
        container.grid_columnconfigure(0,weight=1)

        #adding a menubar#
        self.menuBar = tk.Menu(master=self)
        self.filemenu = tk.Menu(self.menuBar, tearoff=0)
        self.filemenu.add_command(label="Open", command=self.browse_file)
        self.filemenu.add_command(label="Quit!", command=self.quit)
        self.menuBar.add_cascade(label="File", menu=self.filemenu)
        self.config(menu=self.menuBar)

        self.frames={}

        for F in (HRXPSPlotter, SurveyXPSPlotter):

            frame=F(container,self)

            self.frames[F]=frame

            frame.grid(row=0,column=1,sticky='nsew')

        self.show_frame(HRXPSPlotter)

    def show_frame(self, cont):
        frame=self.frames[cont]
        frame.tkraise()

    #Question if it should be here because maybe overwrites the filename   form other window?
    def browse_file(self):
        self.filename =  filedialog.askopenfilename(initialdir = "E:/Images",title = "choose your file",filetypes = (("txt files","*.txt"),("all files","*.*")))
        print(self.filename)
    def printFN(self):
        print(self.filename)

class HRXPSPlotter(tk.Frame):

    def __init__(self,parent, controller):
        tk.Frame.__init__(self,parent)
        lable=tk.Label(self,text='Sart Page',font=LARGE_FONT)
        lable.pack(pady=10,padx=10)
        #button to go to another page
        button1=tk.Button(self, text='Visit Page 1',command=lambda:controller.show_frame(SurveyXPSPlotter))
        button1.pack()

class SurveyXPSPlotter(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        lable=tk.Label(self,text='Page One',font=LARGE_FONT)
        lable.pack(pady=10,padx=10)
        button1=tk.Button(self, text='Back to Page 1',command=lambda:controller.show_frame(HRXPSPlotter))
        button1.pack()

app=XPSPlotApp()
app.mainloop()
</code>```

The program has two pages (because I want to use different plotter) and a menu which can open a file from a directory.

Now I want to implement a function which plots the filename+filepath when I  click a button, but I do not get it work? The problem is simply that I do not really know where I have to define the function — in the __init__ or in the subclasses? and also...

How the command=lambda:controller works, it is still magic for me!

Why are the subclasses (e.g. pageOne) methods of tk.Frame and not tk.Tk like the __init__?

答:
I'm not going to address all your three sub-questions directly because it would wind-up being a whole mini-tutorial on tkinter. However I can show you how to add a Button to do the plotting. Note especially the lines with the comment # ADDED on them.

Below a modified version of your code with a number of things added showing where and how to put a plotting function function could be put in. I've also changed the coding style so it follows the PEP 8 - Style Guide for Python Code more closely and is much more readable.

In a several spots I also changed the name of variables to make it clearer how this kind of gui architecture based on tkinter operates.

```<code>import tkinter as tk
from tkinter import filedialog
LARGE_FONT=('Verdana', 12)

class XPSPlotApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        container = tk.Frame(self)
        container.pack(side='top', fill='both', expand=True)
        container.grid_rowconfigure(0, weight=1)  # 0 is min size
        container.grid_columnconfigure(0, weight=1)

        # Add menubar and subcommands.
        self.menuBar = tk.Menu(master=self)
        self.filemenu = tk.Menu(self.menuBar, tearoff=0)
        self.filemenu.add_command(label="Open", command=self.browse_file)
        self.filemenu.add_command(label="Plot", command=self.plot_file)  # ADDED
        self.filemenu.add_command(label="Quit!", command=self.quit)
        self.menuBar.add_cascade(label="File", menu=self.filemenu)
        self.config(menu=self.menuBar)

        self.frames={}

        for FrameSubclass in (HRXPSPlotter, SurveyXPSPlotter):
            frame = FrameSubclass(container, self)  # create class instance.
            self.frames[FrameSubclass] = frame
            frame.grid(row=0, column=1, sticky='nsew')

        self.show_frame(HRXPSPlotter)

    def show_frame(self, subclass):
        frame = self.frames[subclass]
        frame.tkraise()

    def browse_file(self):
        self.filename = filedialog.askopenfilename(
            initialdir="E:/Images", title="Choose your file",
            filetypes=(("text files", "*.txt"), ("all files", "*.*"))
        )
        print(self.filename)

    def plot_file(self):  # ADDED
        try:
            print('Plotting:', self.filename)
        except AttributeError:
            print('No filename has been selected to plot!')

class HRXPSPlotter(tk.Frame):
    def __init__(self, parent, controller):
        super().__init__(parent)
        label = tk.Label(self, text='Start Page', font=LARGE_FONT)
        label.pack(pady=10, padx=10)
        # Button to go to another page.
        button1 = tk.Button(self, text='Visit Page 1',
                        command=lambda: controller.show_frame(SurveyXPSPlotter))
        button1.pack()

class SurveyXPSPlotter(tk.Frame):
    def __init__(self, parent, controller):
        super().__init__(parent)
        label = tk.Label(self, text='Page One', font=LARGE_FONT)
        label.pack(pady=10, padx=10)
        # Button to go to another page.
        button1 = tk.Button(self, text='Back to Page 1',
                        command=lambda: controller.show_frame(HRXPSPlotter))
        button1.pack()

app=XPSPlotApp()
app.mainloop()
</code>```

The command=lambda: controller.show_frame(<tk.Frame subclass>) arguments used to construct the tk.Buttons creates an anonymous function which calls controller.show_frame(<tk.Frame subclass>) when the corresponding button is pressed (as opposed to it happening as the Button itself is created).

The show_frame() function looks up the Frame subclass instance in the self.frames dictionary that was created in the XPSPlotApp class __init__() method and "raises" it so it becomes as the top-most frame displayed (which effectively hides all the rest of them which are the same size and at the same position but now "below" it).

Body:
I am starting with python and I already created a nice plotting function with matplotlib. Now I want to insert the function into a GUI using tkinter.
As I learned from youtube and this forum I should use classes.
Unfortunately I have some problems with that. What I have so far (where I do not understand everything in detail) is:

import tkinter as tk
from tkinter import filedialog

LARGE_FONT=('Verdana',12)

class XPSPlotApp(tk.Tk):

    def __init__(self, *args,**kwargs):
        tk.Tk.__init__(self, *args,**kwargs)
        container=tk.Frame(self)

        container.pack(side='top',fill='both',expand=True)
        container.grid_rowconfigure(0,weight=1)#0 is min size
        container.grid_columnconfigure(0,weight=1)

        #adding a menubar#
        self.menuBar = tk.Menu(master=self)
        self.filemenu = tk.Menu(self.menuBar, tearoff=0)
        self.filemenu.add_command(label="Open", command=self.browse_file)
        self.filemenu.add_command(label="Quit!", command=self.quit)
        self.menuBar.add_cascade(label="File", menu=self.filemenu)
        self.config(menu=self.menuBar)

        self.frames={}

        for F in (HRXPSPlotter, SurveyXPSPlotter):

            frame=F(container,self)

            self.frames[F]=frame

            frame.grid(row=0,column=1,sticky='nsew')

        self.show_frame(HRXPSPlotter)

    def show_frame(self, cont):
        frame=self.frames[cont]
        frame.tkraise()

    #Question if it should be here because maybe overwrites the filename   form other window?
    def browse_file(self):
        self.filename =  filedialog.askopenfilename(initialdir = "E:/Images",title = "choose your file",filetypes = (("txt files","*.txt"),("all files","*.*")))
        print(self.filename)
    def printFN(self):
        print(self.filename)

class HRXPSPlotter(tk.Frame):

    def __init__(self,parent, controller):
        tk.Frame.__init__(self,parent)
        lable=tk.Label(self,text='Sart Page',font=LARGE_FONT)
        lable.pack(pady=10,padx=10)
        #button to go to another page
        button1=tk.Button(self, text='Visit Page 1',command=lambda:controller.show_frame(SurveyXPSPlotter))
        button1.pack()

class SurveyXPSPlotter(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        lable=tk.Label(self,text='Page One',font=LARGE_FONT)
        lable.pack(pady=10,padx=10)
        button1=tk.Button(self, text='Back to Page 1',command=lambda:controller.show_frame(HRXPSPlotter))
        button1.pack()

app=XPSPlotApp()
app.mainloop()

The program has two pages (because I want to use different plotter) and a menu which can open a file from a directory.

Now I want to implement a function which plots the filename+filepath when I  click a button, but I do not get it work? The problem is simply that I do not really know where I have to define the function — in the __init__ or in the subclasses? and also...

How the command=lambda:controller works, it is still magic for me!

Why are the subclasses (e.g. pageOne) methods of tk.Frame and not tk.Tk like the __init__?

Body:
I'm not going to address all your three sub-questions directly because it would wind-up being a whole mini-tutorial on tkinter. However I can show you how to add a Button to do the plotting. Note especially the lines with the comment # ADDED on them.

Below a modified version of your code with a number of things added showing where and how to put a plotting function function could be put in. I've also changed the coding style so it follows the PEP 8 - Style Guide for Python Code more closely and is much more readable.

In a several spots I also changed the name of variables to make it clearer how this kind of gui architecture based on tkinter operates.

import tkinter as tk
from tkinter import filedialog
LARGE_FONT=('Verdana', 12)

class XPSPlotApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        container = tk.Frame(self)
        container.pack(side='top', fill='both', expand=True)
        container.grid_rowconfigure(0, weight=1)  # 0 is min size
        container.grid_columnconfigure(0, weight=1)

        # Add menubar and subcommands.
        self.menuBar = tk.Menu(master=self)
        self.filemenu = tk.Menu(self.menuBar, tearoff=0)
        self.filemenu.add_command(label="Open", command=self.browse_file)
        self.filemenu.add_command(label="Plot", command=self.plot_file)  # ADDED
        self.filemenu.add_command(label="Quit!", command=self.quit)
        self.menuBar.add_cascade(label="File", menu=self.filemenu)
        self.config(menu=self.menuBar)

        self.frames={}

        for FrameSubclass in (HRXPSPlotter, SurveyXPSPlotter):
            frame = FrameSubclass(container, self)  # create class instance.
            self.frames[FrameSubclass] = frame
            frame.grid(row=0, column=1, sticky='nsew')

        self.show_frame(HRXPSPlotter)

    def show_frame(self, subclass):
        frame = self.frames[subclass]
        frame.tkraise()

    def browse_file(self):
        self.filename = filedialog.askopenfilename(
            initialdir="E:/Images", title="Choose your file",
            filetypes=(("text files", "*.txt"), ("all files", "*.*"))
        )
        print(self.filename)

    def plot_file(self):  # ADDED
        try:
            print('Plotting:', self.filename)
        except AttributeError:
            print('No filename has been selected to plot!')

class HRXPSPlotter(tk.Frame):
    def __init__(self, parent, controller):
        super().__init__(parent)
        label = tk.Label(self, text='Start Page', font=LARGE_FONT)
        label.pack(pady=10, padx=10)
        # Button to go to another page.
        button1 = tk.Button(self, text='Visit Page 1',
                        command=lambda: controller.show_frame(SurveyXPSPlotter))
        button1.pack()

class SurveyXPSPlotter(tk.Frame):
    def __init__(self, parent, controller):
        super().__init__(parent)
        label = tk.Label(self, text='Page One', font=LARGE_FONT)
        label.pack(pady=10, padx=10)
        # Button to go to another page.
        button1 = tk.Button(self, text='Back to Page 1',
                        command=lambda: controller.show_frame(HRXPSPlotter))
        button1.pack()

app=XPSPlotApp()
app.mainloop()

The command=lambda: controller.show_frame(<tk.Frame subclass>) arguments used to construct the tk.Buttons creates an anonymous function which calls controller.show_frame(<tk.Frame subclass>) when the corresponding button is pressed (as opposed to it happening as the Button itself is created).

The show_frame() function looks up the Frame subclass instance in the self.frames dictionary that was created in the XPSPlotApp class __init__() method and "raises" it so it becomes as the top-most frame displayed (which effectively hides all the rest of them which are the same size and at the same position but now "below" it).


问:
return null notificationId in NotificationHub
I use Microsoft.Azure.NotificationHubs in VS2017. when I try to send a notification by SendAppleNativeNotificationAsync method this doesn't return notificationId, this is null.  I have the Standard pricing for Notification Hub

enter image description here

答: I worked with REST API I did a simple test and it worked correctly Send an APNS Native Notification, azure-notificationhubs here I found everything necessary for my problem</p>


问:
WordPress Plugin Development
Besides the CODEX what resources do you recommend to help a person new to creating plugins help create a WordPress plugin. I have an idea, but need a bit better explanation than what is in the CODEX to get started.

UPDATE: Is there a book that I could buy to help me out with this?

答:
I think one of the most important resources is the code used in other plugins.

Not necessarily doing what yours does, but ones that use have features you want to implement.

For example, if you want to find how to create an options page, you are going to work it out pretty quickly if you see how all the others do it.

OwnerDisplayName: Mike Wills

ContentLicense: CC BY-SA 2.5

Title: WordPress Plugin Development

LastEditorDisplayName: Mike Wills

OwnerDisplayName: Stephen Baugh


问:
I need help writing a complex SELECT statement
i am trying to write an sql statement that will select items from one table and order it by the result of the other table..

the 2 tables are:

events:
id, name

attendance:
user, event

ive got this statement:

```<code>SELECT *
FROM `attendance`
WHERE event='1'
  AND user IN (1,2,3,4,5,6,7,8,9,10,11,12,13,444,153)
</code>```

I am using this to get the number of friends that coming to event number 1.

now I want to combine that statement with another one to create a statement that select all the events, and order it by the number of friends that going...
how can i write that statement?

Thank you very much, Amir.

答:
You could also use a join like:</p>

```<code>SELECT events.id, COUNT(attendance.user) AS attending
FROM attendance INNER JOIN events ON attendance.event = events.id
WHERE (attendance.user IN (1,2,3,4,5,6,7,8,9,10,11,12,13,444,153))
GROUP BY events.id
ORDER BY attending DESC
</code>```

Body:
i am trying to write an sql statement that will select items from one table and order it by the result of the other table..

the 2 tables are:

events:
id, name

attendance:
user, event

ive got this statement:

SELECT *
FROM `attendance`
WHERE event='1'
  AND user IN (1,2,3,4,5,6,7,8,9,10,11,12,13,444,153)

I am using this to get the number of friends that coming to event number 1.

now I want to combine that statement with another one to create a statement that select all the events, and order it by the number of friends that going...
how can i write that statement?

Thank you very much, Amir.

Body:
You could also use a join like:

SELECT events.id, COUNT(attendance.user) AS attending
FROM attendance INNER JOIN events ON attendance.event = events.id
WHERE (attendance.user IN (1,2,3,4,5,6,7,8,9,10,11,12,13,444,153))
GROUP BY events.id
ORDER BY attending DESC


问:
what tag should i use for text? html5
What tag should i use for small amount of text. For example it is good practise to use p tag for every "small" text like here "username" and pasword" or for day/month/year, should i use also p tag? </p>

```<code><div class="login-area">
    <p>Username:</p>
    <input type="text">
    <p>Password:</p>
    <input type="password">
</div>
</code>```

答:
Use</p>

```<code><label for="name">Your Form label</label>
<input type="text" name="name">

<label for="password">Your Form label</label>
<input type="password" name="password>
</code>```

Title: what tag should i use for text? html5

Body:
What tag should i use for small amount of text. For example it is good practise to use p tag for every "small" text like here "username" and pasword" or for day/month/year, should i use also p tag?

Username:

    <input type="text">

Password:

    <input type="password">

Body:
Use

<label for="name">Your Form label</label>
<input type="text" name="name">

<label for="password">Your Form label</label>
<input type="password" name="password>


问:
C# LUIS Chatbot extract all intents from LuisResult
I have a chatbot that is connected with LUIS, I know although the dialog will only go into the one with the highest matching intent, however I would still want to display the scores of the rest of the intents, is there a way to do that?
I already have

```<code>[LuisModel("XXXX", "XXXX", Verbose = true)]
</code>```

So far this is what I'm using:

```<code>    [LuisIntent("")]
    [LuisIntent("None")]
    public async Task None(IDialogContext context, LuisResult result)
    {

        string allIntents = "";

        //Loop throught all intents found in JSON
        foreach (var foundIntent in result.Intents)
        {
            allIntents += ("Intent: " + foundIntent.Intent + "\n\n" + "Score: " + foundIntent.Score + "\n\n");
        }
        await context.PostAsync(allIntents);
        context.Wait(this.MessageReceived);
    }
</code>```

And my JSON is like

```<code>{
  "query": "hey there",
  "topScoringIntent": {
  "intent": "None",
  "score": 0.17292054
  },
  "intents": [
    {
      "intent": "None",
      "score": 0.17292054
    },
    {
      "intent": "intentSearch",
      "score": 0.122199811
    },
    {
      "intent": "fromIntent",
      "score": 0.0327471271
    },
    {
      "intent": "goWithIntent",
      "score": 0.010828237
    }
  ],
  "entities": []
}
</code>```

However my bot will only return the none intent and its score. Is there a way of returning all of the intent inside a dialog?

EDIT: The answer somehow worked on a new project and I don't know why

答:
You have to set the verbose flag to true in your LuisModelAttribute like so:

```<code>[LuisModel("e7a9c2d5-0b92-47d3-9d73-xxxxxxxxxxxx",
"4941fa348c49494db1e8e8xxxxxxxxxx", Verbose = true)]
</code>```

This is the code to get all the intents, which you can get your scores from

```<code>    [LuisIntent("greeting")]
    public async Task Greeting(IDialogContext context, LuisResult result)
    {
        string allIntents = "";
        //Loop throught all intents found in JSON
        foreach (var foundIntent in result.Intents)
        {
            allIntents += ("Intent: " + foundIntent.Intent + "\n\n" + "Score: " + foundIntent.Score + "\n\n");
        }
        await context.PostAsync(allIntents);

        context.Wait(this.MessageReceived);
    }
</code>```

using this code I got this result:

Body:
I have a chatbot that is connected with LUIS, I know although the dialog will only go into the one with the highest matching intent, however I would still want to display the scores of the rest of the intents, is there a way to do that?
I already have

[LuisModel("XXXX", "XXXX", Verbose = true)]

So far this is what I'm using:

    [LuisIntent("")]
    [LuisIntent("None")]
    public async Task None(IDialogContext context, LuisResult result)
    {

        string allIntents = "";

        //Loop throught all intents found in JSON
        foreach (var foundIntent in result.Intents)
        {
            allIntents += ("Intent: " + foundIntent.Intent + "\n\n" + "Score: " + foundIntent.Score + "\n\n");
        }
        await context.PostAsync(allIntents);
        context.Wait(this.MessageReceived);
    }

And my JSON is like

{
  "query": "hey there",
  "topScoringIntent": {
  "intent": "None",
  "score": 0.17292054
  },
  "intents": [
    {
      "intent": "None",
      "score": 0.17292054
    },
    {
      "intent": "intentSearch",
      "score": 0.122199811
    },
    {
      "intent": "fromIntent",
      "score": 0.0327471271
    },
    {
      "intent": "goWithIntent",
      "score": 0.010828237
    }
  ],
  "entities": []
}

However my bot will only return the none intent and its score. Is there a way of returning all of the intent inside a dialog?

EDIT: The answer somehow worked on a new project and I don't know why

Body:
You have to set the verbose flag to true in your LuisModelAttribute like so:

[LuisModel("e7a9c2d5-0b92-47d3-9d73-xxxxxxxxxxxx",
"4941fa348c49494db1e8e8xxxxxxxxxx", Verbose = true)]

This is the code to get all the intents, which you can get your scores from

    [LuisIntent("greeting")]
    public async Task Greeting(IDialogContext context, LuisResult result)
    {
        string allIntents = "";
        //Loop throught all intents found in JSON
        foreach (var foundIntent in result.Intents)
        {
            allIntents += ("Intent: " + foundIntent.Intent + "\n\n" + "Score: " + foundIntent.Score + "\n\n");
        }
        await context.PostAsync(allIntents);

        context.Wait(this.MessageReceived);
    }

using this code I got this result:


问:
Find the second largest number in array
I have an array of three element like [31,23,12] and I want to find the second largest element and its related position without rearranging the array.

Example :

```<code>array = [21,23,34]
</code>```

Second_largest = 23;

Position is = 1;

答:
```<code>var elements = [21,23,34]

var largest = -Infinity

// Find largest
for (var i=0; i < elements.length; i++) {
  if (elements[i] > largest) largest = elements[i]
}

var second_largest = -Infinity
var second_largest_position = -1

// Find second largest
for (var i=0; i < elements.length; i++) {
  if (elements[i] > second_largest && elements[i] < largest) {
    second_largest = elements[i]
    second_largest_position = i
  }
}

console.log(second_largest, second_largest_position)
</code>```

Title: Find the second largest number in array

Body:
I have an array of three element like [31,23,12] and I want to find the second largest element and its related position without rearranging the array.

Example :

array = [21,23,34]

Second_largest = 23;

Position is = 1;


问:
National Weather Service API Internal server error

I keep getting error 500 when trying to get data using their new API, even when I include UserAgent string that they request: https://forecast-v3.weather.gov/documentation

```<code>HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://api.weather.gov/points/40,-90/forecast/hourly");

request.UserAgent = "WeatherTest/v1.0 (http://www.website.com/; Email@email.com)";

// exception occurs here
using (Stream stream = request.GetResponse().GetResponseStream())
{
    using (StreamReader streamReader = new StreamReader(stream))
    {
        var jsonData = streamReader.ReadToEnd();
    }
}
</code>```

But I can use the endpoint on a browser just fine using the same url: https://api.weather.gov/points/40,-90/forecast/hourly

I have also tested this code with another API (Weather Underground) and it works, but my boss wants me to use National Weather Service api instead. Any help is appreciated!

答:
The documentation you provided gives you an answer:

Content Negotiation

The API will use Accept headers to modify the
response returned. See the FAQ tab for more information. Parameters
include: Version of the API, defaults to the oldest Format of the
response, default in specifications An example of the Accept header
would be "Accept: application/vnd.noaa.dwml+xml;version=1"

Add:

request.Headers.Add("Accept", "application/vnd.noaa.dwml+json;version=1"); and you'll get a JSON response.

Body:
I keep getting error 500 when trying to get data using their new API, even when I include UserAgent string that they request: https://forecast-v3.weather.gov/documentation

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://api.weather.gov/points/40,-90/forecast/hourly");

request.UserAgent = "WeatherTest/v1.0 (http://www.website.com/; Email@email.com)";

// exception occurs here
using (Stream stream = request.GetResponse().GetResponseStream())
{
    using (StreamReader streamReader = new StreamReader(stream))
    {
        var jsonData = streamReader.ReadToEnd();
    }
}

But I can use the endpoint on a browser just fine using the same url: https://api.weather.gov/points/40,-90/forecast/hourly

I have also tested this code with another API (Weather Underground) and it works, but my boss wants me to use National Weather Service api instead. Any help is appreciated!


问:
ASP secure user login in different access level and restricted access pages
Im building an ASP website with user login. Does any one knows what is the best and must secure way to make login page and make pages restricted access? I know some ways and used them for some website but sometimes they were not that secure. There is couple access level for this website. Admin, User, Sales Team, and couple more. Thanks.</p>

答:
Assuming you are using IIS as your web server, you can let it handle your website security by using the different available authentication methods.

http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/9b619620-4f88-488b-8243-e6bc7caf61ad.mspx?mfr=true

http://www.authenticationtutorial.com/tutorial/

Perhaps the best authentication method for you would be Windows Integrated Authentication since it allows you to create groups (or maybe use the existing ones) to give access to certain directories or pages.


问:
Vector of object pointers returns odd values
I have a task to create an object Stos which would feature a heap of objects Obiekt, to which I could add things as I please.

In order to make the program better support dynamic arrays I decided to use a Vector.
The whole implementation seems to run perfectly, the returned value is completely off.
Here is an example with code:

```<code>class Obiekt {
private:
    int id;

public:
    Obiekt::Obiekt(int i) {
        id = i;
    }

    void Obiekt::display() {
        cout << "This object has id of: " << id << endl;
    }
};

class Stos {
private:
    vector < Obiekt* > stos;
public:
    Stos::Stos(Obiekt n) {
        add(n);
    }

    void Stos::add(Obiekt n) {
        stos.push_back(&n);
    }

    void Stos::display() {
        cout << endl << "===HEAP DISPLAY===" << endl;
        for (int i = 0; i < stos.size(); i++) {
            stos[i]->display();
        }
    }
};

void Zad1()
{
    Obiekt obj1(5);
    Obiekt obj2(23);

    Stos s1(obj1);
    s1.add(obj2);
    s1.display();

    getchar();
}
</code>```

And the outcome being:

===HEAP DISPLAY===

This object has id of: -858993460

This object has id of:9805925

I'm not a cpp expert, and believe the issue is related to the stos.push_back(&n) portion, but I can't catch the moment the id gets so distorted.

It's probably a noob question, so sorry for that on start.

Any help would be amazing.

答:
The issue with your code as O'Neil correctly explained is that you're adding the pointer to a copy of the Obiekt object. So basically, you create your object in main, and pass it to the constructor and the .add function in Stos. You then add the pointer to the vector. When the function finishes, the copy that was passed is destroyed and the pointer in your vector is dangling.
There are two ways to fix this:

1 Pass by reference

This is very simple, basically you just add an ampersand to your function parameters. For instance:

```<code>void Stos::add(Obiekt &n) {
    stos.push_back(&n);
}
</code>```

This will ensure that the object isn't destroyed at the end of the function

2 Don't use pointers

Another way of getting your problem to work is to avoid using pointers at all. Your vector will actually copy the contents of the Obiekt object into it. For example:

```<code>vector < Obiekt > stos; // notice how we define it without the pointer type
</code>```

...

```<code>void Stos::add(Obiekt n) {
    stos.push_back(n); // Creates copy which will then contain the correct value
}
</code>```

Body:
I have a task to create an object Stos which would feature a heap of objects Obiekt, to which I could add things as I please.

In order to make the program better support dynamic arrays I decided to use a Vector.
The whole implementation seems to run perfectly, the returned value is completely off.
Here is an example with code:

class Obiekt {
private:
    int id;

public:
    Obiekt::Obiekt(int i) {
        id = i;
    }

    void Obiekt::display() {
        cout << "This object has id of: " << id << endl;
    }
};

class Stos {
private:
    vector < Obiekt* > stos;
public:
    Stos::Stos(Obiekt n) {
        add(n);
    }

    void Stos::add(Obiekt n) {
        stos.push_back(&n);
    }

    void Stos::display() {
        cout << endl << "===HEAP DISPLAY===" << endl;
        for (int i = 0; i < stos.size(); i++) {
            stos[i]->display();
        }
    }
};

void Zad1()
{
    Obiekt obj1(5);
    Obiekt obj2(23);

    Stos s1(obj1);
    s1.add(obj2);
    s1.display();

    getchar();
}

And the outcome being:

===HEAP DISPLAY===

This object has id of: -858993460

This object has id of:9805925

I'm not a cpp expert, and believe the issue is related to the stos.push_back(&n) portion, but I can't catch the moment the id gets so distorted.

It's probably a noob question, so sorry for that on start.

Any help would be amazing.

Body:
The issue with your code as O'Neil correctly explained is that you're adding the pointer to a copy of the Obiekt object. So basically, you create your object in main, and pass it to the constructor and the .add function in Stos. You then add the pointer to the vector. When the function finishes, the copy that was passed is destroyed and the pointer in your vector is dangling.
There are two ways to fix this:

1 Pass by reference

This is very simple, basically you just add an ampersand to your function parameters. For instance:

void Stos::add(Obiekt &n) {
    stos.push_back(&n);
}

This will ensure that the object isn't destroyed at the end of the function

2 Don't use pointers

Another way of getting your problem to work is to avoid using pointers at all. Your vector will actually copy the contents of the Obiekt object into it. For example:

vector < Obiekt > stos; // notice how we define it without the pointer type

...

void Stos::add(Obiekt n) {
    stos.push_back(n); // Creates copy which will then contain the correct value
}


问:
Create a bar diagram with matplotlib with x-axis date and width is a time-delta
I have a simple dataset that I would like to display in a bar chart corresponding to a weight collected at different times. I want it cumulative with an error bar I have estimated before. Since the weight corresponds to an accumulation during a certain period of time, I want the bar to be the width of the time it represents.

The entry file is in the form:

```<code>Date    Weight  Deviation
2017-05-04  500 100
2017-05-08  7.4 0.3
2017-05-13  6.4 0.3
2017-05-21  8.7 0.27
2017-06-06  16.8    0.7
2017-06-07  14.4    0.6
2017-06-18  13.7    0.6
2017-06-25  16.3    0.7
2017-07-02  17  0
2017-07-09  17  0
2017-07-26  20  0
2017-08-11  19  0
2017-08-23  12  0
2017-09-03  27  0
2017-09-11  15  0
2017-09-16  60  0
</code>```

Here the code:

```<code>import os, sys, datetime
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.dates as mdates

DATA  = np.genfromtxt(Path_to_File, dtype=[('Date','datetime64[D]'),('Weight', 'float32'), ('Deviation', 'float32')], delimiter ='\t', skip_header = 1)
Days  = np.zeros(len(DATA)-1, dtype = 'datetime64[D]')
Duration = np.zeros(len(DATA)-1, dtype = 'timedelta64[D]')
for i in range(1, len(DATA)):
    DayOut = DATA[i][0]
    DayIn  = DATA[i-1][0]
    Duration[i-1] = DayOut - DayIn
    Days[i-1] = DayIn + Duration[i-1]/2

fig2 = plt.figure()
ax = fig2.add_subplot(111)
fig2.suptitle('FigureTitle', fontsize=16)
ax.xaxis_date()
ax.xaxis.set_major_formatter(mdates.DateFormatter('%d/%m'))
ax.xaxis.set_major_locator(mdates.DayLocator(interval=7))
ax.bar(Days, DATA['Weight'].cumsum()[1:], width=Duration, yerr = DATA['Deviation'][1:])
ax.set_ylabel('Cumulative weight (kg)')
ax.set_xlabel('Date')
plt.show()
</code>```

I get this error message

```<code>Cannot cast ufunc less input from dtype('<m8[D]') to dtype('<m8') with casting rule 'same_kind'
</code>```

It is tricky because I think it gets annoyed between dates(datetime64), the Days array and duration for the width (timedelta64), the Duration array.
I am a bit stuck, I suppose I have to do a duration only axis? Any experience, or suggestions?
Thanks in advance

答:
Matplotlib cannot handle numpy.datetime64 currently. It would rely on pandas for the conversion to datetime objects. Since here you would anyways want to set the width of the bars in days, an easy solution without the use of pandas would be to convert the dates to datetime (done below via .tolist()). The duration can be calculated by first converting the datetimes to numbers and taking their difference.

```<code>Days  = [x.tolist() for x in DATA["Date"]]
Duration = np.diff(mdates.date2num(Days))
</code>```

I guess the rest of the code can stay the same, although I did not understand why you'd leave out the first element so I changed that to omitting the last ([:-1]).

```<code>import numpy as np
import matplotlib.pyplot as plt
import matplotlib.dates as mdates

DATA  = np.genfromtxt("data/datetabdelim.txt", dtype=[('Date','datetime64[D]'),('Weight', 'float32'), ('Deviation', 'float32')],
                                                      delimiter ='\t', skip_header = 1)
Days  = [x.tolist() for x in DATA["Date"]]
Duration = np.diff(mdates.date2num(Days))

fig2 = plt.figure()
ax = fig2.add_subplot(111)
fig2.suptitle('FigureTitle', fontsize=16)
ax.xaxis_date()
ax.xaxis.set_major_formatter(mdates.DateFormatter('%d/%m'))
ax.xaxis.set_major_locator(mdates.DayLocator(interval=7))
bars = ax.bar(Days[:-1], DATA['Weight'].cumsum()[:-1], width=Duration,
              yerr = DATA['Deviation'][:-1], edgecolor="k", alpha=0.5, align="edge")
ax.set_ylabel('Cumulative weight (kg)')
ax.set_xlabel('Date')
fig2.autofmt_xdate()
plt.show()
</code>```

Body:
I have a simple dataset that I would like to display in a bar chart corresponding to a weight collected at different times. I want it cumulative with an error bar I have estimated before. Since the weight corresponds to an accumulation during a certain period of time, I want the bar to be the width of the time it represents.

The entry file is in the form:

Date    Weight  Deviation
2017-05-04  500 100
2017-05-08  7.4 0.3
2017-05-13  6.4 0.3
2017-05-21  8.7 0.27
2017-06-06  16.8    0.7
2017-06-07  14.4    0.6
2017-06-18  13.7    0.6
2017-06-25  16.3    0.7
2017-07-02  17  0
2017-07-09  17  0
2017-07-26  20  0
2017-08-11  19  0
2017-08-23  12  0
2017-09-03  27  0
2017-09-11  15  0
2017-09-16  60  0

Here the code:

import os, sys, datetime
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.dates as mdates

DATA  = np.genfromtxt(Path_to_File, dtype=[('Date','datetime64[D]'),('Weight', 'float32'), ('Deviation', 'float32')], delimiter ='\t', skip_header = 1)
Days  = np.zeros(len(DATA)-1, dtype = 'datetime64[D]')
Duration = np.zeros(len(DATA)-1, dtype = 'timedelta64[D]')
for i in range(1, len(DATA)):
    DayOut = DATA[i][0]
    DayIn  = DATA[i-1][0]
    Duration[i-1] = DayOut - DayIn
    Days[i-1] = DayIn + Duration[i-1]/2

fig2 = plt.figure()
ax = fig2.add_subplot(111)
fig2.suptitle('FigureTitle', fontsize=16)
ax.xaxis_date()
ax.xaxis.set_major_formatter(mdates.DateFormatter('%d/%m'))
ax.xaxis.set_major_locator(mdates.DayLocator(interval=7))
ax.bar(Days, DATA['Weight'].cumsum()[1:], width=Duration, yerr = DATA['Deviation'][1:])
ax.set_ylabel('Cumulative weight (kg)')
ax.set_xlabel('Date')
plt.show()

I get this error message

Cannot cast ufunc less input from dtype('<m8[D]') to dtype('<m8') with casting rule 'same_kind'

It is tricky because I think it gets annoyed between dates(datetime64), the Days array and duration for the width (timedelta64), the Duration array.
I am a bit stuck, I suppose I have to do a duration only axis? Any experience, or suggestions?
Thanks in advance

Body:
Matplotlib cannot handle numpy.datetime64 currently. It would rely on pandas for the conversion to datetime objects. Since here you would anyways want to set the width of the bars in days, an easy solution without the use of pandas would be to convert the dates to datetime (done below via .tolist()). The duration can be calculated by first converting the datetimes to numbers and taking their difference.

Days  = [x.tolist() for x in DATA["Date"]]
Duration = np.diff(mdates.date2num(Days))

I guess the rest of the code can stay the same, although I did not understand why you'd leave out the first element so I changed that to omitting the last ([:-1]).

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.dates as mdates

DATA  = np.genfromtxt("data/datetabdelim.txt", dtype=[('Date','datetime64[D]'),('Weight', 'float32'), ('Deviation', 'float32')],
                                                      delimiter ='\t', skip_header = 1)
Days  = [x.tolist() for x in DATA["Date"]]
Duration = np.diff(mdates.date2num(Days))

fig2 = plt.figure()
ax = fig2.add_subplot(111)
fig2.suptitle('FigureTitle', fontsize=16)
ax.xaxis_date()
ax.xaxis.set_major_formatter(mdates.DateFormatter('%d/%m'))
ax.xaxis.set_major_locator(mdates.DayLocator(interval=7))
bars = ax.bar(Days[:-1], DATA['Weight'].cumsum()[:-1], width=Duration,
              yerr = DATA['Deviation'][:-1], edgecolor="k", alpha=0.5, align="edge")
ax.set_ylabel('Cumulative weight (kg)')
ax.set_xlabel('Date')
fig2.autofmt_xdate()
plt.show()


问:
How to format dates and times?
I'm trying to get make a comments section for a website with the backend written in python. As of now, everything works fine except I cannot figure out how to format the date and time the way I want.

What I am trying to have at the time of posting is either of these:

Posted on Tue, 06/12/18 at - 11:20

or

Posted on 06/12/18 at - 11:21

Currently, what I have when the method is called is this:

```<code>import time
from datetime import *

time = ("Posted on " + str(datetime.now().day) + "/"
        + str(datetime.now().month) + " at: " + str(datetime.now().hour)
        + ":" + str(datetime.now().minute))
</code>```

答:
You can use datetime.datetime.strftime() to build any format you want:

```<code>import datetime

time = datetime.datetime.now().strftime("Posted on %d/%m/%y at - %H:%M")

print(time)  # Posted on 07/12/17 at - 00:29
</code>```

Read up more on special classes you can use when building your date: strftime() and strptime() Behavior

Title: How to format dates and times?

Body:
I'm trying to get make a comments section for a website with the backend written in python. As of now, everything works fine except I cannot figure out how to format the date and time the way I want.

What I am trying to have at the time of posting is either of these:

Posted on Tue, 06/12/18 at - 11:20

or

Posted on 06/12/18 at - 11:21

Currently, what I have when the method is called is this:

import time
from datetime import *

time = ("Posted on " + str(datetime.now().day) + "/"
        + str(datetime.now().month) + " at: " + str(datetime.now().hour)
        + ":" + str(datetime.now().minute))

Body:
You can use datetime.datetime.strftime() to build any format you want:

import datetime

time = datetime.datetime.now().strftime("Posted on %d/%m/%y at - %H:%M")

print(time)  # Posted on 07/12/17 at - 00:29

Read up more on special classes you can use when building your date: strftime() and strptime() Behavior


Title: How to format dates and times?

Body:
datetime.datetime.now().strftime('%d/%m/%y at - %H:%M')
'06/12/17 at - 16:29'


问:
Mixing columns and rows resolving in an error
I'm trying to create a form for my app containing two columns inside a row. Should look something like this:

But when I run this code:

```<code>@override
  Widget build(BuildContext context) {
    return /*new Padding (
      padding: const EdgeInsets.all(15.0),
      child: */new ListView (
      //mainAxisAlignment: MainAxisAlignment.start,
        children: <Widget>[new Row (children: <Widget>[
          // Goal  + Amount
          new ListTile (
              title: new Column (
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[new Expanded(child: new TextField(
                    controller: widget._NameController,
                    style: new TextStyle (
                      fontSize: 20.0,
                      color: Colors.black,
                    ),
                    decoration: new InputDecoration(
                        labelText: 'Name'
                    ),
                  )), new Expanded(child:
                  new FlatButton(
                    onPressed: _showDatePicker,
                    child: new Text(
                        PARTIAL_DATE_FORMAT.format(_pickedDate)),
                  )),
                  ]
              )
          ),
          // Goal Deadline
          new ListTile (
              title: new Column (
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[new Expanded(child: new ListTile (
                      title: new TextField(
                        //controller: widget._TextController,,
                        style: new TextStyle (
                            fontSize: 20.0,
                            color: Colors.black
                        ),
                        decoration: new InputDecoration(
                            labelText: 'Amount'
                        ),
                      )
                  )), new Expanded(child:
                  new FlatButton(
                    onPressed: _showTimePicker,
                    child: new Text(_pickedTime.format(context)),
                  )),
                  ]
              )
          ),
        ]),
        // Goal Description
        new ListTile (
            title: new TextField(
              controller: widget._DescriptionController,
              style: new TextStyle (
                  fontSize: 20.0,
                  color: Colors.black
              ),
              decoration: new InputDecoration(
                  labelText: 'Description'
              ),
            )
        ),
        ]
    );
  }
</code>```

It resolves in this error:

```<code>I/flutter ( 2837): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter ( 2837): The following assertion was thrown during performLayout():
I/flutter ( 2837): RenderFlex children have non-zero flex but incoming width constraints are unbounded.
I/flutter ( 2837): When a row is in a parent that does not provide a finite width constraint, for example if it is in a
I/flutter ( 2837): horizontal scrollable, it will try to shrink-wrap its children along the horizontal axis. Setting a
I/flutter ( 2837): flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining
I/flutter ( 2837): space in the horizontal direction.
I/flutter ( 2837): These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child
I/flutter ( 2837): cannot simultaneously expand to fit its parent.
I/flutter ( 2837): Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible
I/flutter ( 2837): children (using Flexible rather than Expanded). This will allow the flexible children to size
I/flutter ( 2837): themselves to less than the infinite remaining space they would otherwise be forced to take, and
I/flutter ( 2837): then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum
I/flutter ( 2837): constraints provided by the parent.
I/flutter ( 2837): The affected RenderFlex is:
I/flutter ( 2837):   RenderFlex#770e0 relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837): The creator information is set to:
I/flutter ( 2837):   Row ← Padding ← ConstrainedBox ← Container ← Listener ← _GestureSemantics ← RawGestureDetector ←
I/flutter ( 2837):   GestureDetector ← InkWell ← ListTile ← Row ← RepaintBoundary-[<0>] ← ⋯
I/flutter ( 2837): The nearest ancestor providing an unbounded width constraint is:
I/flutter ( 2837):   RenderFlex#47431 relayoutBoundary=up3 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):   creator: Row ← RepaintBoundary-[<0>] ← NotificationListener<KeepAliveNotification> ← KeepAlive ←
I/flutter ( 2837):   AutomaticKeepAlive ← SliverList ← Viewport ← _ScrollableScope ← IgnorePointer-[GlobalKey#60f18] ←
I/flutter ( 2837):   Listener ← _GestureSemantics ←
I/flutter ( 2837):   RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#f4728] ← ⋯
I/flutter ( 2837):   parentData: <none> (can use size)
I/flutter ( 2837):   constraints: BoxConstraints(w=381.4, 0.0<=h<=Infinity)
I/flutter ( 2837):   size: MISSING
I/flutter ( 2837):   direction: horizontal
I/flutter ( 2837):   mainAxisAlignment: start
I/flutter ( 2837):   mainAxisSize: max
I/flutter ( 2837):   crossAxisAlignment: center
I/flutter ( 2837):   textDirection: ltr
I/flutter ( 2837):   verticalDirection: downSee also: https://flutter.io/layout/
I/flutter ( 2837): If this message did not help you determine the problem, consider using debugDumpRenderTree():
I/flutter ( 2837):   https://flutter.io/debugging/#rendering-layer
I/flutter ( 2837):   http://docs.flutter.io/flutter/rendering/debugDumpRenderTree.html
I/flutter ( 2837): If none of the above helps enough to fix this problem, please don't hesitate to file a bug:
I/flutter ( 2837):   https://github.com/flutter/flutter/issues/new
I/flutter ( 2837): When the exception was thrown, this was the stack:
I/flutter ( 2837): #0      RenderFlex.performLayout.<anonymous closure> (package:flutter/src/rendering/flex.dart:690:11)
I/flutter ( 2837): #1      RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:711:10)
I/flutter ( 2837): #2      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #3      RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11)
I/flutter ( 2837): #4      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #5      RenderConstrainedBox.performLayout (package:flutter/src/rendering/proxy_box.dart:257:13)
I/flutter ( 2837): #6      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #7      RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #8      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #9      RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #10     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #11     RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:737:15)
I/flutter ( 2837): #12     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #13     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #14     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #15     RenderSliverList.performLayout (package:flutter/src/rendering/sliver_list.dart:164:27)
I/flutter ( 2837): #16     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #17     RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:286:13)
I/flutter ( 2837): #18     RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:979:12)
I/flutter ( 2837): #19     RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:903:20)
I/flutter ( 2837): #20     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #21     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #22     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #23     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #24     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #25     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #26     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #27     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #28     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #29     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #30     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #31     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #32     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #33     RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11)
I/flutter ( 2837): #34     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #35     MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:124:11)
I/flutter ( 2837): #36     _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:91:7)
I/flutter ( 2837): #37     MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:194:7)
I/flutter ( 2837): #38     RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:338:14)
I/flutter ( 2837): #39     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #40     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #41     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #42     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #43     _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1005:24)
I/flutter ( 2837): #44     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #45     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #46     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #47     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #48     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #49     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #50     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #51     RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2747:14)
I/flutter ( 2837): #52     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #53     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #54     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #55     RenderStack.performLayout (package:flutter/src/rendering/stack.dart:466:15)
I/flutter ( 2837): #56     RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1837:7)
I/flutter ( 2837): #57     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:1126:18)
I/flutter ( 2837): #58     BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:262
:19)
I/flutter ( 2837): #59     BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/bin
ding.dart:581:22)
I/flutter ( 2837): #60     BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rende
ring/binding.dart:200:5)
I/flutter ( 2837): #61     BindingBase&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:713:15)
I/flutter ( 2837): #62     BindingBase&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:649:9)
I/flutter ( 2837): #63     _invoke (file:///b/build/slave/Linux_Engine/build/src/flutter/lib/ui/hooks.dart:91)
I/flutter ( 2837): #64     _drawFrame (file:///b/build/slave/Linux_Engine/build/src/flutter/lib/ui/hooks.dart:80)
I/flutter ( 2837): The following RenderObject was being processed when the exception was fired:
I/flutter ( 2837):   RenderFlex#770e0 relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):   creator: Row ← Padding ← ConstrainedBox ← Container ← Listener ← _GestureSemantics ←
I/flutter ( 2837):   RawGestureDetector ← GestureDetector ← InkWell ← ListTile ← Row ← RepaintBoundary-[<0>] ← ⋯
I/flutter ( 2837):   parentData: offset=Offset(0.0, 0.0) (can use size)
I/flutter ( 2837):   constraints: BoxConstraints(0.0<=w<=Infinity, h=56.0)
I/flutter ( 2837):   size: MISSING
I/flutter ( 2837):   direction: horizontal
I/flutter ( 2837):   mainAxisAlignment: start
I/flutter ( 2837):   mainAxisSize: max
I/flutter ( 2837):   crossAxisAlignment: center
I/flutter ( 2837):   textDirection: ltr
I/flutter ( 2837):   verticalDirection: down
I/flutter ( 2837): This RenderObject had the following descendants (showing up to depth 5):
I/flutter ( 2837):   RenderFlex#5610b NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):     RenderSemanticsGestureHandler#6d25d NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):       RenderPointerListener#4eb7b NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):         RenderConstrainedBox#3d105 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):           RenderStack#f6a43 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):     RenderConstrainedBox#13bd4 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):       RenderSemanticsGestureHandler#905d0 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):         RenderPointerListener#ec2c3 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):           RenderPadding#2b663 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837): ════════════════════════════════════════════════════════════════════════════════════════════════════
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/sliver_multi_box_adaptor.dart': Failed assertion: line 458 pos 12: 'child.hasSiz
e': is not true.
I/flutter ( 2837): Another exception was thrown: NoSuchMethodError: The method 'debugAssertIsValid' was called on null.
I/flutter ( 2837): Another exception was thrown: NoSuchMethodError: The getter 'visible' was called on null.
</code>```

I'm very new to flutter and having a lot of trouble working with it due to the lack of information on the internet about that.

答:
I have a created a simple example to show you how you can approach building the desired layout, the usage of ListTile in your code is really confusing and should not be used in this way. The information you provided are not clear enough on what the different elements in your layout represents. That is why I am filling them with a Container, you should be able to provide any widget as child of the container to get started.

```<code>import "package:flutter/material.dart";

class Layout extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(),
      body: new Padding(
          padding: const EdgeInsets.all(30.0),
          child:new Column(
        children: <Widget>[
          new Row(
            children: <Widget>[
              new SizedBox(
               height: 30.0 ,
                width: 200.0,
                child: new Container(color: Colors.redAccent,),
              ),
              new Container(width: 40.0,),
              new SizedBox(
                height: 30.0,
                width: 50.0,
                child: new Container(color:Colors.amberAccent),
              )
            ],
          ),
          new Container(height: 30.0,),
          new Row(
            children: <Widget>[
              new SizedBox(
                height: 40.0 ,
                width: 100.0,
                child: new Container(color: Colors.redAccent,),
              ),
              new Container(width: 140.0,),
              new SizedBox(
                height: 40.0,
                width: 50.0,
                child: new Container(color:Colors.amberAccent),
              )
            ],
          ),
          new Container(height: 30.0,),
           new Container(color: Colors.tealAccent,width: 290.0,height: 320.0,)

        ],
      ),),
    );
  }
}
</code>```

Update

I believe you are trying to do similar layout to the following one, the real problem with your code is using ListTile, ListTiles are used to store minimal information (like contact lists for example), and should not be used to contain nested widgets because they are limited in size.

Secondly, I was only doing the previous example as a demonstration, however, yes you are correct about the fixed size problems. In order to avoid this you can use check FractionallySizedBox, or like I did at the very end of the ListView here, using MediaQuery.of(context).size.height*0.3 gave me a Container with height that is 30% of the total screen height.

```<code>    import "package:flutter/material.dart";

class Layout extends StatefulWidget {
  @override
  _LayoutState createState() => new _LayoutState();
}

class _LayoutState extends State<Layout> {
  String time = "Set Time";
  String date = "Set Date ";

  String dropDownString;

  _showDate(BuildContext context) async {
    var datePicked = await showDatePicker(context: context,
        initialDate: new DateTime.now(),
        firstDate: new DateTime(2010, 2),
        lastDate: new DateTime(2018, 1));

    setState(() {
      date = "${datePicked.month}/${datePicked.day}/${datePicked.year}";
    });
  }

  _showTime(BuildContext context) async {
    var timePicked = await showTimePicker(
        context: context, initialTime: new TimeOfDay.now());
    setState(() {
      time = "${timePicked.hour}:${timePicked.minute} ";
    });
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(title: new Text("Layout Example"),),
      body: new Padding(padding: const EdgeInsets.all(20.0),
        child: new ListView(
          //shrinkWrap: true,
          children: <Widget>[
            new Row(
              children: <Widget>[

                new Expanded(child: new TextField()),
                new Expanded(child: new FlatButton(
                    onPressed: () => _showDate(context),
                    child: new Text(date))),

              ],
            ),
            new Row(
              children: <Widget>[
                new Expanded(child: new TextField()),
                new Expanded(child: new FlatButton(
                    onPressed: () => _showTime(context),
                    child: new Text(time))),
              ],),
            new TextField(
              maxLines: 5,
            ),
            new Container(
              height: MediaQuery.of(context).size.height*0.3,
              color: Colors.tealAccent,
            )

          ],
        ),
      ),
    );
  }
}
</code>```

Body:
I'm trying to create a form for my app containing two columns inside a row. Should look something like this:

But when I run this code:

@override
  Widget build(BuildContext context) {
    return /*new Padding (
      padding: const EdgeInsets.all(15.0),
      child: */new ListView (
      //mainAxisAlignment: MainAxisAlignment.start,
        children: <Widget>[new Row (children: <Widget>[
          // Goal  + Amount
          new ListTile (
              title: new Column (
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[new Expanded(child: new TextField(
                    controller: widget._NameController,
                    style: new TextStyle (
                      fontSize: 20.0,
                      color: Colors.black,
                    ),
                    decoration: new InputDecoration(
                        labelText: 'Name'
                    ),
                  )), new Expanded(child:
                  new FlatButton(
                    onPressed: _showDatePicker,
                    child: new Text(
                        PARTIAL_DATE_FORMAT.format(_pickedDate)),
                  )),
                  ]
              )
          ),
          // Goal Deadline
          new ListTile (
              title: new Column (
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[new Expanded(child: new ListTile (
                      title: new TextField(
                        //controller: widget._TextController,,
                        style: new TextStyle (
                            fontSize: 20.0,
                            color: Colors.black
                        ),
                        decoration: new InputDecoration(
                            labelText: 'Amount'
                        ),
                      )
                  )), new Expanded(child:
                  new FlatButton(
                    onPressed: _showTimePicker,
                    child: new Text(_pickedTime.format(context)),
                  )),
                  ]
              )
          ),
        ]),
        // Goal Description
        new ListTile (
            title: new TextField(
              controller: widget._DescriptionController,
              style: new TextStyle (
                  fontSize: 20.0,
                  color: Colors.black
              ),
              decoration: new InputDecoration(
                  labelText: 'Description'
              ),
            )
        ),
        ]
    );
  }

It resolves in this error:

I/flutter ( 2837): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter ( 2837): The following assertion was thrown during performLayout():
I/flutter ( 2837): RenderFlex children have non-zero flex but incoming width constraints are unbounded.
I/flutter ( 2837): When a row is in a parent that does not provide a finite width constraint, for example if it is in a
I/flutter ( 2837): horizontal scrollable, it will try to shrink-wrap its children along the horizontal axis. Setting a
I/flutter ( 2837): flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining
I/flutter ( 2837): space in the horizontal direction.
I/flutter ( 2837): These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child
I/flutter ( 2837): cannot simultaneously expand to fit its parent.
I/flutter ( 2837): Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible
I/flutter ( 2837): children (using Flexible rather than Expanded). This will allow the flexible children to size
I/flutter ( 2837): themselves to less than the infinite remaining space they would otherwise be forced to take, and
I/flutter ( 2837): then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum
I/flutter ( 2837): constraints provided by the parent.
I/flutter ( 2837): The affected RenderFlex is:
I/flutter ( 2837):   RenderFlex#770e0 relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837): The creator information is set to:
I/flutter ( 2837):   Row ← Padding ← ConstrainedBox ← Container ← Listener ← _GestureSemantics ← RawGestureDetector ←
I/flutter ( 2837):   GestureDetector ← InkWell ← ListTile ← Row ← RepaintBoundary-[<0>] ← ⋯
I/flutter ( 2837): The nearest ancestor providing an unbounded width constraint is:
I/flutter ( 2837):   RenderFlex#47431 relayoutBoundary=up3 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):   creator: Row ← RepaintBoundary-[<0>] ← NotificationListener<KeepAliveNotification> ← KeepAlive ←
I/flutter ( 2837):   AutomaticKeepAlive ← SliverList ← Viewport ← _ScrollableScope ← IgnorePointer-[GlobalKey#60f18] ←
I/flutter ( 2837):   Listener ← _GestureSemantics ←
I/flutter ( 2837):   RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#f4728] ← ⋯
I/flutter ( 2837):   parentData: <none> (can use size)
I/flutter ( 2837):   constraints: BoxConstraints(w=381.4, 0.0<=h<=Infinity)
I/flutter ( 2837):   size: MISSING
I/flutter ( 2837):   direction: horizontal
I/flutter ( 2837):   mainAxisAlignment: start
I/flutter ( 2837):   mainAxisSize: max
I/flutter ( 2837):   crossAxisAlignment: center
I/flutter ( 2837):   textDirection: ltr
I/flutter ( 2837):   verticalDirection: downSee also: https://flutter.io/layout/
I/flutter ( 2837): If this message did not help you determine the problem, consider using debugDumpRenderTree():
I/flutter ( 2837):   https://flutter.io/debugging/#rendering-layer
I/flutter ( 2837):   http://docs.flutter.io/flutter/rendering/debugDumpRenderTree.html
I/flutter ( 2837): If none of the above helps enough to fix this problem, please don't hesitate to file a bug:
I/flutter ( 2837):   https://github.com/flutter/flutter/issues/new
I/flutter ( 2837): When the exception was thrown, this was the stack:
I/flutter ( 2837): #0      RenderFlex.performLayout.<anonymous closure> (package:flutter/src/rendering/flex.dart:690:11)
I/flutter ( 2837): #1      RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:711:10)
I/flutter ( 2837): #2      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #3      RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11)
I/flutter ( 2837): #4      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #5      RenderConstrainedBox.performLayout (package:flutter/src/rendering/proxy_box.dart:257:13)
I/flutter ( 2837): #6      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #7      RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #8      RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #9      RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #10     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #11     RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:737:15)
I/flutter ( 2837): #12     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #13     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #14     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #15     RenderSliverList.performLayout (package:flutter/src/rendering/sliver_list.dart:164:27)
I/flutter ( 2837): #16     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #17     RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:286:13)
I/flutter ( 2837): #18     RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:979:12)
I/flutter ( 2837): #19     RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:903:20)
I/flutter ( 2837): #20     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #21     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #22     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #23     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #24     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #25     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #26     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #27     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #28     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #29     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #30     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #31     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #32     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #33     RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:197:11)
I/flutter ( 2837): #34     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #35     MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:124:11)
I/flutter ( 2837): #36     _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:91:7)
I/flutter ( 2837): #37     MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:194:7)
I/flutter ( 2837): #38     RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:338:14)
I/flutter ( 2837): #39     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #40     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #41     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #42     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #43     _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1005:24)
I/flutter ( 2837): #44     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #45     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #46     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #47     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #48     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #49     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #50     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #51     RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:2747:14)
I/flutter ( 2837): #52     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #53     RenderBox&RenderObjectWithChildMixin&RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:107:13)
I/flutter ( 2837): #54     RenderObject.layout (package:flutter/src/rendering/object.dart:1962:7)
I/flutter ( 2837): #55     RenderStack.performLayout (package:flutter/src/rendering/stack.dart:466:15)
I/flutter ( 2837): #56     RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1837:7)
I/flutter ( 2837): #57     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:1126:18)
I/flutter ( 2837): #58     BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:262
:19)
I/flutter ( 2837): #59     BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/bin
ding.dart:581:22)
I/flutter ( 2837): #60     BindingBase&SchedulerBinding&GestureBinding&ServicesBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rende
ring/binding.dart:200:5)
I/flutter ( 2837): #61     BindingBase&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:713:15)
I/flutter ( 2837): #62     BindingBase&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:649:9)
I/flutter ( 2837): #63     _invoke (file:///b/build/slave/Linux_Engine/build/src/flutter/lib/ui/hooks.dart:91)
I/flutter ( 2837): #64     _drawFrame (file:///b/build/slave/Linux_Engine/build/src/flutter/lib/ui/hooks.dart:80)
I/flutter ( 2837): The following RenderObject was being processed when the exception was fired:
I/flutter ( 2837):   RenderFlex#770e0 relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):   creator: Row ← Padding ← ConstrainedBox ← Container ← Listener ← _GestureSemantics ←
I/flutter ( 2837):   RawGestureDetector ← GestureDetector ← InkWell ← ListTile ← Row ← RepaintBoundary-[<0>] ← ⋯
I/flutter ( 2837):   parentData: offset=Offset(0.0, 0.0) (can use size)
I/flutter ( 2837):   constraints: BoxConstraints(0.0<=w<=Infinity, h=56.0)
I/flutter ( 2837):   size: MISSING
I/flutter ( 2837):   direction: horizontal
I/flutter ( 2837):   mainAxisAlignment: start
I/flutter ( 2837):   mainAxisSize: max
I/flutter ( 2837):   crossAxisAlignment: center
I/flutter ( 2837):   textDirection: ltr
I/flutter ( 2837):   verticalDirection: down
I/flutter ( 2837): This RenderObject had the following descendants (showing up to depth 5):
I/flutter ( 2837):   RenderFlex#5610b NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):     RenderSemanticsGestureHandler#6d25d NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):       RenderPointerListener#4eb7b NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):         RenderConstrainedBox#3d105 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):           RenderStack#f6a43 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):     RenderConstrainedBox#13bd4 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):       RenderSemanticsGestureHandler#905d0 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):         RenderPointerListener#ec2c3 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837):           RenderPadding#2b663 NEEDS-LAYOUT NEEDS-PAINT
I/flutter ( 2837): ════════════════════════════════════════════════════════════════════════════════════════════════════
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/box.dart': Failed assertion: line 1433 pos 12: 'hasSize': is not true.
I/flutter ( 2837): Another exception was thrown: 'package:flutter/src/rendering/sliver_multi_box_adaptor.dart': Failed assertion: line 458 pos 12: 'child.hasSiz
e': is not true.
I/flutter ( 2837): Another exception was thrown: NoSuchMethodError: The method 'debugAssertIsValid' was called on null.
I/flutter ( 2837): Another exception was thrown: NoSuchMethodError: The getter 'visible' was called on null.

I'm very new to flutter and having a lot of trouble working with it due to the lack of information on the internet about that.

Body:
I have a created a simple example to show you how you can approach building the desired layout, the usage of ListTile in your code is really confusing and should not be used in this way. The information you provided are not clear enough on what the different elements in your layout represents. That is why I am filling them with a Container, you should be able to provide any widget as child of the container to get started.

import "package:flutter/material.dart";

class Layout extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(),
      body: new Padding(
          padding: const EdgeInsets.all(30.0),
          child:new Column(
        children: <Widget>[
          new Row(
            children: <Widget>[
              new SizedBox(
               height: 30.0 ,
                width: 200.0,
                child: new Container(color: Colors.redAccent,),
              ),
              new Container(width: 40.0,),
              new SizedBox(
                height: 30.0,
                width: 50.0,
                child: new Container(color:Colors.amberAccent),
              )
            ],
          ),
          new Container(height: 30.0,),
          new Row(
            children: <Widget>[
              new SizedBox(
                height: 40.0 ,
                width: 100.0,
                child: new Container(color: Colors.redAccent,),
              ),
              new Container(width: 140.0,),
              new SizedBox(
                height: 40.0,
                width: 50.0,
                child: new Container(color:Colors.amberAccent),
              )
            ],
          ),
          new Container(height: 30.0,),
           new Container(color: Colors.tealAccent,width: 290.0,height: 320.0,)

        ],
      ),),
    );
  }
}

Update

I believe you are trying to do similar layout to the following one, the real problem with your code is using ListTile, ListTiles are used to store minimal information (like contact lists for example), and should not be used to contain nested widgets because they are limited in size.

Secondly, I was only doing the previous example as a demonstration, however, yes you are correct about the fixed size problems. In order to avoid this you can use check FractionallySizedBox, or like I did at the very end of the ListView here, using MediaQuery.of(context).size.height*0.3 gave me a Container with height that is 30% of the total screen height.

    import "package:flutter/material.dart";

class Layout extends StatefulWidget {
  @override
  _LayoutState createState() => new _LayoutState();
}

class _LayoutState extends State<Layout> {
  String time = "Set Time";
  String date = "Set Date ";

  String dropDownString;

  _showDate(BuildContext context) async {
    var datePicked = await showDatePicker(context: context,
        initialDate: new DateTime.now(),
        firstDate: new DateTime(2010, 2),
        lastDate: new DateTime(2018, 1));

    setState(() {
      date = "${datePicked.month}/${datePicked.day}/${datePicked.year}";
    });
  }

  _showTime(BuildContext context) async {
    var timePicked = await showTimePicker(
        context: context, initialTime: new TimeOfDay.now());
    setState(() {
      time = "${timePicked.hour}:${timePicked.minute} ";
    });
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(title: new Text("Layout Example"),),
      body: new Padding(padding: const EdgeInsets.all(20.0),
        child: new ListView(
          //shrinkWrap: true,
          children: <Widget>[
            new Row(
              children: <Widget>[

                new Expanded(child: new TextField()),
                new Expanded(child: new FlatButton(
                    onPressed: () => _showDate(context),
                    child: new Text(date))),

              ],
            ),
            new Row(
              children: <Widget>[
                new Expanded(child: new TextField()),
                new Expanded(child: new FlatButton(
                    onPressed: () => _showTime(context),
                    child: new Text(time))),
              ],),
            new TextField(
              maxLines: 5,
            ),
            new Container(
              height: MediaQuery.of(context).size.height*0.3,
              color: Colors.tealAccent,
            )

          ],
        ),
      ),
    );
  }
}