text: """A CallTip window class for Tkinter/IDLE.
  
  After ToolTip.py, which uses ideas gleaned from PySol
  Used by the CallTips IDLE extension.
  
  """
  from Tkinter import *
  
  HIDE_VIRTUAL_EVENT_NAME = "<<calltipwindow-hide>>"
  HIDE_SEQUENCES = ("<Key-Escape>", "<FocusOut>")
  CHECKHIDE_VIRTUAL_EVENT_NAME = "<<calltipwindow-checkhide>>"
  CHECKHIDE_SEQUENCES = ("<KeyRelease>", "<ButtonRelease>")
  CHECKHIDE_TIME = 100 # miliseconds
  
  MARK_RIGHT = "calltipwindowregion_right"
  
  class CallTip:
  
      def __init__(self, widget):
          self.widget = widget
          self.tipwindow = self.label = None
          self.parenline = self.parencol = None
          self.lastline = None
          self.hideid = self.checkhideid = None
  
      def position_window(self):
          """Check if needs to reposition the window, and if so - do it."""
          curline = int(self.widget.index("insert").split('.')[0])
          if curline == self.lastline:
              return
          self.lastline = curline
          self.widget.see("insert")
          if curline == self.parenline:
              box = self.widget.bbox("%d.%d" % (self.parenline,
                                                self.parencol))
          else:
              box = self.widget.bbox("%d.0" % curline)
          if not box:
              box = list(self.widget.bbox("insert"))
              # align to left of window
              box[0] = 0
              box[2] = 0
          x = box[0] + self.widget.winfo_rootx() + 2
          y = box[1] + box[3] + self.widget.winfo_rooty()
          self.tipwindow.wm_geometry("+%d+%d" % (x, y))
  
      def showtip(self, text, parenleft, parenright):
          """Show the calltip, bind events which will close it and reposition it.
          """
          # truncate overly long calltip
          if len(text) >= 79:
              textlines = text.splitlines()
              for i, line in enumerate(textlines):
                  if len(line) > 79:
                      textlines[i] = line[:75] + ' ...'
              text = '\n'.join(textlines)
          self.text = text
          if self.tipwindow or not self.text:
              return
  
          self.widget.mark_set(MARK_RIGHT, parenright)
          self.parenline, self.parencol = map(
              int, self.widget.index(parenleft).split("."))
  
          self.tipwindow = tw = Toplevel(self.widget)
          self.position_window()
          # remove border on calltip window
          tw.wm_overrideredirect(1)
          try:
              # This command is only needed and available on Tk >= 8.4.0 for OSX
              # Without it, call tips intrude on the typing process by grabbing
              # the focus.
              tw.tk.call("::tk::unsupported::MacWindowStyle", "style", tw._w,
                         "help", "noActivates")
          except TclError:
              pass
          self.label = Label(tw, text=self.text, justify=LEFT,
                             background="#ffffe0", relief=SOLID, borderwidth=1,
                             font = self.widget['font'])
          self.label.pack()
  
          self.checkhideid = self.widget.bind(CHECKHIDE_VIRTUAL_EVENT_NAME,
                                              self.checkhide_event)
          for seq in CHECKHIDE_SEQUENCES:
              self.widget.event_add(CHECKHIDE_VIRTUAL_EVENT_NAME, seq)
          self.widget.after(CHECKHIDE_TIME, self.checkhide_event)
          self.hideid = self.widget.bind(HIDE_VIRTUAL_EVENT_NAME,
                                         self.hide_event)
          for seq in HIDE_SEQUENCES:
              self.widget.event_add(HIDE_VIRTUAL_EVENT_NAME, seq)
  
      def checkhide_event(self, event=None):
          if not self.tipwindow:
              # If the event was triggered by the same event that unbinded
              # this function, the function will be called nevertheless,
              # so do nothing in this case.
              return
          curline, curcol = map(int, self.widget.index("insert").split('.'))
          if curline < self.parenline or \
             (curline == self.parenline and curcol <= self.parencol) or \
             self.widget.compare("insert", ">", MARK_RIGHT):
              self.hidetip()
          else:
              self.position_window()
              self.widget.after(CHECKHIDE_TIME, self.checkhide_event)
  
      def hide_event(self, event):
          if not self.tipwindow:
              # See the explanation in checkhide_event.
              return
          self.hidetip()
  
      def hidetip(self):
          if not self.tipwindow:
              return
  
          for seq in CHECKHIDE_SEQUENCES:
              self.widget.event_delete(CHECKHIDE_VIRTUAL_EVENT_NAME, seq)
          self.widget.unbind(CHECKHIDE_VIRTUAL_EVENT_NAME, self.checkhideid)
          self.checkhideid = None
          for seq in HIDE_SEQUENCES:
              self.widget.event_delete(HIDE_VIRTUAL_EVENT_NAME, seq)
          self.widget.unbind(HIDE_VIRTUAL_EVENT_NAME, self.hideid)
          self.hideid = None
  
          self.label.destroy()
          self.label = None
          self.tipwindow.destroy()
          self.tipwindow = None
  
          self.widget.mark_unset(MARK_RIGHT)
          self.parenline = self.parencol = self.lastline = None
  
      def is_active(self):
          return bool(self.tipwindow)
  
  
  
  ###############################
  #
  # Test Code
  #
  class container: # Conceptually an editor_window
      def __init__(self):
          root = Tk()
          text = self.text = Text(root)
          text.pack(side=LEFT, fill=BOTH, expand=1)
          text.insert("insert", "string.split")
          root.update()
          self.calltip = CallTip(text)
  
          text.event_add("<<calltip-show>>", "(")
          text.event_add("<<calltip-hide>>", ")")
          text.bind("<<calltip-show>>", self.calltip_show)
          text.bind("<<calltip-hide>>", self.calltip_hide)
  
          text.focus_set()
          root.mainloop()
  
      def calltip_show(self, event):
          self.calltip.showtip("Hello world")
  
      def calltip_hide(self, event):
          self.calltip.hidetip()
  
  def main():
      # Test code
      c=container()
  
  if __name__=='__main__':
      main()
  