title: Issue Adding Android Dialog
body: <p>so I am currently working on a basic event organiser, it will store events for a convention and allow the user to store the events they're interested in.</p>
  
  <p>However I am having issues, as i want to add a dialog to each buttons press so it will display the events information and give the user the option if they want to add it or not.</p>
  
  <p>The issue i am having with the code is the following, which occours onclick.</p>
  
  <p><strong><em>android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application</em></strong></p>
  
  <p>Below is the code for the eventbutton itself which is displayed on screen </p>
  
  <pre><code>   public class EventButton extends Button
  {
      public Button button = this;
      public Event event;
      public String eventHost;
      public String eventName;
      public String eventLocation;
      public Calendar eventDate;
      private LinearLayout screen;
  
      public EventButton(Context context , Event pEvent){
          super(context);
          eventDate = pEvent.eventDate;
          eventName = pEvent.eventName;
          eventHost = pEvent.eventHost;
          eventLocation = pEvent.eventLocation;
          event = pEvent;
          setOnClick();
  
          this.setText(eventName + "\n " + eventHost);
      }
  
       public void setOnClick() {
          button.setOnClickListener(new View.OnClickListener() {
              public void onClick(View v) {
  
  
  
                  int timeTilEvent =getTimeDifference();
                  int day = eventDate.get(eventDate.DAY_OF_MONTH);
                  int month=eventDate.get(eventDate.MONTH);
                  int year=eventDate.get(eventDate.YEAR);
                  int hour=eventDate.get(eventDate.HOUR_OF_DAY);
                  int minute=eventDate.get(eventDate.MINUTE);
                  String minutestring=""+ minute;
  
                  if(minutestring.length()==1){
                      minutestring = "0"+minute;
                  }
                  String dateOutput= day + "/" + month +"/" + year + "\n " + hour + ":" + minutestring;
  
                  AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
                  builder.setMessage("Event:" + eventName + "\n Host:" + eventHost + "\n Location: " + eventLocation + "\n When: " + dateOutput);
                  builder.setTitle("do you wish to add this event to your watch list?");
  
                  if(!FileManager.eventList.contains(event)) {
                      builder.setPositiveButton("add interest", new DialogInterface.OnClickListener() {
                          public void onClick(DialogInterface dialog, int id) {
                              FileManager.writeToFile(new Event(eventHost, eventName, eventLocation, eventDate), getContext());
                              FileManager.readFromFile(getContext());
                          }
                      });
                  }
                  else if(FileManager.eventList.contains(event)) {
                      builder.setPositiveButton("remove interest", new DialogInterface.OnClickListener() {
                          public void onClick(DialogInterface dialog, int id) {
                              FileManager.eventList.remove(event);
                              FileManager.writeToFile(new Event(eventHost, eventName, eventLocation, eventDate), getContext());
                              FileManager.readFromFile(getContext());
                          }
                      });
                  }
  
                  builder.setPositiveButton("cancel", new DialogInterface.OnClickListener() {
                      public void onClick(DialogInterface dialog, int id) {
                      }
                  });
  
                  AlertDialog dialog = builder.create();
                  dialog.show();
  </code></pre>
  
  <p>Main class (showing how the buttons are created)</p>
  
  <pre><code>  public class MainActivity extends AppCompatActivity {
  
      public Calendar setupDate(int year, int month, int day , int hour, int minute){
          return new GregorianCalendar(year,month,day,hour,minute);
      }    
  
      ArrayList&lt;EventButton&gt; buttons = new ArrayList&lt;EventButton&gt;();
  
      public void addButtonToList(String pHost, String pName,String pEventLocation, Calendar pDate){
          Event event = new Event(pHost, pName, pEventLocation, pDate);
          buttons.add(new EventButton(getBaseContext(),event));
      }
  
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.content_main);
  
          addButtonToList("Host ", " Event", "location", setupDate(2016, 04, 03, 10, 00));
         addButtonToList("Host ", " Event", "location", setupDate(2016, 04, 03, 10, 00));
  
  
  
          LinearLayout ll = (LinearLayout) findViewById(R.id.LinearLayout1);
          LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(ActionBar.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
  
          for(int count=0;count &lt; buttons.size();count++){
              if(buttons.get(count) != null) {
                  buttons.get(count).AddButtonToScreen(ll, lp);
              }
          }
  
  
  
          }
  </code></pre>
  
  <p>Any help will be greatly appreciated thanks</p>
  
  <p>(the catlog output if anyone was interested or needed it)</p>
  
  <pre><code>    04-03 18:26:20.267 4335-4335/? E/Zygote: v2
  04-03 18:26:20.267 4335-4335/? I/libpersona: KNOX_SDCARD checking this for 10160
  04-03 18:26:20.267 4335-4335/? I/libpersona: KNOX_SDCARD not a persona
  04-03 18:26:20.267 4335-4335/? I/SELinux: Function: selinux_compare_spd_ram , priority [2] , priority version is VE=SEPF_SM-G361F_5.1.1_0043
  04-03 18:26:20.267 4335-4335/? E/SELinux: [DEBUG] get_category: variable seinfo: default sensitivity: NULL, cateogry: NULL
  04-03 18:26:20.277 4335-4335/? I/art: Late-enabling -Xcheck:jni
  04-03 18:26:20.287 4335-4335/? D/TimaKeyStoreProvider: in addTimaSignatureService
  04-03 18:26:20.307 4335-4335/? D/TimaKeyStoreProvider: TimaSignature is unavailable
  04-03 18:26:20.307 4335-4335/? D/ActivityThread: Added TimaKesytore provider
  04-03 18:26:20.307 4335-4335/? I/SAMP: ActivityThread() - SAMP_ENABLE : true
  04-03 18:26:20.357 4335-4335/com.example.daniel.myapplication D/ContextImpl: ContextImpl running for user UserHandle{0} 0
  04-03 18:26:20.367 4335-4335/com.example.daniel.myapplication D/ContextImpl: ContextImpl running for user UserHandle{0} 0
  04-03 18:26:20.367 4335-4335/com.example.daniel.myapplication W/ResourcesManager: getTopLevelResources: null for user  0
  04-03 18:26:20.437 4335-4335/com.example.daniel.myapplication D/ContextImpl: ContextImpl running for user UserHandle{0} 0
  04-03 18:26:20.447 4335-4335/com.example.daniel.myapplication D/ContextImpl: ContextImpl running for user UserHandle{0} 0
  04-03 18:26:20.447 4335-4335/com.example.daniel.myapplication W/ResourcesManager: getTopLevelResources: null for user  0
  04-03 18:26:20.447 4335-4335/com.example.daniel.myapplication W/ResourcesManager: getTopLevelResources: null for user  0
  04-03 18:26:20.457 4335-4335/com.example.daniel.myapplication D/DisplayManager: DisplayManager()
  04-03 18:26:20.497 4335-4335/com.example.daniel.myapplication D/PhoneWindow: *FMB* installDecor mIsFloating : false
  04-03 18:26:20.497 4335-4335/com.example.daniel.myapplication D/PhoneWindow: *FMB* installDecor flags : -2139029248
  04-03 18:26:20.557 4335-4398/com.example.daniel.myapplication D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
  04-03 18:26:20.577 4335-4335/com.example.daniel.myapplication D/PhoneWindow: *FMB* isFloatingMenuEnabled mFloatingMenuBtn : null
  04-03 18:26:20.577 4335-4335/com.example.daniel.myapplication D/PhoneWindow: *FMB* isFloatingMenuEnabled return false
  04-03 18:26:20.627 4335-4398/com.example.daniel.myapplication I/OpenGLRenderer: Initialized EGL, version 1.4
  04-03 18:26:20.627 4335-4398/com.example.daniel.myapplication D/GC: &lt;tid=4398&gt; OES20 ===&gt; GC Version   : GC version rls_5011p6_GC5.5.14 
  04-03 18:26:20.637 4335-4398/com.example.daniel.myapplication D/OpenGLRenderer: Enabling debug mode 0
  04-03 18:26:20.757 4335-4335/com.example.daniel.myapplication W/IInputConnectionWrapper: showStatusIcon on inactive InputConnection
  04-03 18:26:20.757 4335-4335/com.example.daniel.myapplication I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@25ba99d time:70384960
  04-03 18:26:32.137 4335-4335/com.example.daniel.myapplication I/Timeline: Timeline: Activity_idle id: android.os.BinderProxy@25ba99d time:70396347
  04-03 18:26:33.527 4335-4335/com.example.daniel.myapplication D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
  04-03 18:26:33.647 4335-4335/com.example.daniel.myapplication D/PhoneWindow: *FMB* installDecor mIsFloating : true
  04-03 18:26:33.647 4335-4335/com.example.daniel.myapplication D/PhoneWindow: *FMB* installDecor flags : 8388610
  04-03 18:26:33.687 4335-4335/com.example.daniel.myapplication D/AndroidRuntime: Shutting down VM
  04-03 18:26:33.687 4335-4335/com.example.daniel.myapplication E/AndroidRuntime: FATAL EXCEPTION: main
                                                                                  Process: com.example.daniel.myapplication, PID: 4335
                                                                                  android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
                                                                                      at android.view.ViewRootImpl.setView(ViewRootImpl.java:578)
                                                                                      at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:282)
                                                                                      at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:85)
                                                                                      at android.app.Dialog.show(Dialog.java:298)
                                                                                      at com.example.daniel.myapplication.EventButton$1.onClick(EventButton.java:195)
                                                                                      at android.view.View.performClick(View.java:5076)
                                                                                      at android.view.View$PerformClick.run(View.java:20279)
                                                                                      at android.os.Handler.handleCallback(Handler.java:739)
                                                                                      at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                                      at android.os.Looper.loop(Looper.java:135)
                                                                                      at android.app.ActivityThread.main(ActivityThread.java:5910)
                                                                                      at java.lang.reflect.Method.invoke(Native Method)
                                                                                      at java.lang.reflect.Method.invoke(Method.java:372)
                                                                                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1405)
                                                                                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1200)
  </code></pre>