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Dialog is not modal when ProgressDialog and Dialog are opened in sequence

I'm running wxPython 4.0.1 msw (phoenix) with Python 3.6.5 on a Windows7 machine, as well as wxPython 2.9.4 with Python 2.7.
I'm observing an issue with a modal dialog, which doesn't block the access to its parent window behind. This only occurs if I run a progress dialog followed by a modal dialog. This behavior is somehow related to custom dialogs. Integrated dialogs like wx.MessageDialog doesn't seem to have this issue.
To isolate the issue, I've written an example. The first two buttons open either the progress or the modal dialog and work properly. The third button opens both dialogs in sequence. In this case the modal functionality of the custom dialog doesn't work and I'm able to access and close the mainframe. Which causes multiple issues.
Dialog is not modal, the main window can be accessed and closed
import wx
class SomeDialog(wx.Dialog):
def __init__(self, parent):
wx.Dialog.__init__(self, parent, title='SomeDialog',
style=wx.DEFAULT_DIALOG_STYLE)
self.button_ok = wx.Button(self, wx.ID_OK, size=(120,-1))
hsizer = wx.BoxSizer(wx.HORIZONTAL)
hsizer.Add(self.button_ok, 0, wx.ALL|wx.ALIGN_CENTER, 10)
self.SetSizer(hsizer)
self.SetSize(self.BestSize)
self.Layout()
class TestFrame(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, -1, size=(400, 400))
self.button_progress = wx.Button(self, -1, 'Show Progress')
self.button_modal = wx.Button(self, -1, 'Show Modal')
self.button_both = wx.Button(self, -1, 'Show Both')
self.Bind(wx.EVT_BUTTON, self.on_button, self.button_progress)
self.Bind(wx.EVT_BUTTON, self.on_button, self.button_modal)
self.Bind(wx.EVT_BUTTON, self.on_button, self.button_both)
sizer = wx.BoxSizer()
sizer.Add(self.button_progress)
sizer.Add(self.button_modal)
sizer.Add(self.button_both)
self.SetSizer(sizer)
def on_button(self, event):
if event.EventObject is self.button_progress:
self._show_progress_dialog()
elif event.EventObject is self.button_modal:
self._show_modal_dialog()
else:
self._show_progress_dialog()
self._show_modal_dialog()
def _show_progress_dialog(self):
max = 10
dlg = wx.ProgressDialog('Progress dialog example', 'Some message',
maximum=max, parent=self,
style=wx.PD_APP_MODAL|wx.PD_AUTO_HIDE)
keepGoing = True
count = 0
while keepGoing and count < max:
count += 1
wx.MilliSleep(250)
wx.Yield()
(keepGoing, skip) = dlg.Update(count)
dlg.Destroy()
def _show_modal_dialog(self):
with SomeDialog(self) as dlg:
dlg.CenterOnParent()
dlg.ShowModal()
if __name__ == '__main__':
app = wx.App()
frame = TestFrame()
frame.Show()
app.MainLoop()
In case this is an issue in the wxpython framework and not an issue with my implementation, it would be great if someone could provide me a workaround to show such dialogs in sequence.

This looks like a bug to me. I'm not sure why its happening, but one workaround would be to use wx.CallLater
changing _show_modal_dialog to:
def _show_modal_dialog(self):
def _make_dialog():
with SomeDialog(self) as dlg:
dlg.CenterOnParent()
dlg.ShowModal()
wx.CallLater(50, _make_dialog) # 50 mils is arbitrary
Seems to resolve the issue of the dialog not acting modalish. The problem with this workaround is that it will be non-blocking, meaning that any code that has to wait for the dialog to return has to be moved into the dialog class or passed to the dialog as a callback.

In the meantime I found a workaround myself which I like to share.
I added a handler catching the windows close event.
class TestFrame(wx.Frame):
def __init__(self):
#...
self.Bind(wx.EVT_CLOSE, self.on_close)
This event function checks if some child dialog is open and modal and performs a veto.
def on_close(self, event):
# In case any modal dialog is open, prevent the frame from closing.
for children in (c for c in self.Children if isinstance(c, wx.Dialog)):
if children.IsModal():
event.Veto()
return
event.Skip()
This is also only a workaround, but I seems to work for my use cases.

Exiting from a thread causes unresponsive GUI

This is a follow-up to my previous question, wxPython popup from calling imported function.
I was able to figure out a way to create a wxPython dialog window to determine if a thread my GUI called should continue its execution. What I did was simply create the dialog window in the thread itself. However, once I made the thread exit by clicking "no" in this popup, the close button in my GUI became unresponsive, and I couldn't close the GUI itself. Once again, your help is much appreciated!
GUI code:
import sys
import os
import re
import subprocess
import threading
import wx
import errno, os, stat, shutil
import extern_func
#this object redirects the external function output to the text box
class RedirectText(object):
def __init__(self,aWxTextCtrl):
self.out=aWxTextCtrl
def write(self,string):
self.out.WriteText(string)
#GUI code here
class progFrame(wx.Frame):
def __init__(self, parent):
wx.Frame.__init__(self, parent, title="functionGUI", size=(800, 600), style=wx.DEFAULT_FRAME_STYLE ^ wx.RESIZE_BORDER)
panel = wx.Panel(self)
#more things....
self.closeButton = wx.Button(panel, wx.ID_OK, "Run", pos=(250, 300))
self.runButton = wx.Button(panel, wx.ID_OK, "Run", pos=(200, 300))
self.out=wx.TextCtrl(panel, style=wx.TE_MULTILINE|wx.VSCROLL|wx.TE_READONLY, pos = (300, 50), size=(500, 200))
#Run button event
self.Bind(wx.EVT_BUTTON, self.OnRun, self.runButton)
#close button event
self.Bind(wx.EVT_BUTTON, self.OnClose, self.closeButton)
#command prompt output to frame
redir=RedirectText(self.out)
sys.stdout=redir
self.Show()
def OnRun(self, event):
t=threading.Thread(target=self.__run)
t.start()
def OnClose(self, event):
self.Destroy()
#external function call
def __run(self):
externFunc()
if __name__ == '__main__':
app = wx.App(False)
progFrame(None)
app.MainLoop()
External function code:
import sys
def externFunc():
print "Starting execution..."
#a bunch of code...
#this is the code for the Yes/No prompt and what introduced the buggy behavior
if(os.path.isdir(mirror_source_path) or os.path.isdir(mirror_dest_path)):
app = wx.App(False)
dlg = wx.MessageDialog(None, "Something bad happened. Continue?","Warning",wx.YES_NO | wx.ICON_QUESTION)
retCode = dlg.ShowModal()
if (retCode == wx.ID_YES):
print "Continuing."
else:
print "Aborted."
return None
sys.exit(0)
dlg.Destroy()
#more function code...
print "Success!"

You cannot have 2 wxPython main loops running at the same time. That will cause some pretty screwy behavior. Personally I think I would split this code into 2 threads. When the first one finishes, it sends a message using wx.CallAfter and pubsub or wx.PostEvent and at that time you can do your if statement in a wxPython handler.
If you continue, then you spin up a second thread with the rest of the function code.

wxPython event starts up at startup

So I am a complete beginner at python and usually code in C/C++ or Java. In the process of developing a GUI my events keep getting called at the start of the program running instead of when I click the button. (i know my indents are wrong because I needed to put it into a code block). How do I make my events only get called when I left click the button?
def __init__(self, parent, title):
super(QuadDash, self).__init__(parent, title=title, size=(1024, 780))
self.SetBackgroundColour("white")
pnl = wx.Panel(self)
cbtn = wx.Button(pnl, label='Start Quad', pos=(20,30))
self.Bind(wx.EVT_LEFT_DOWN, self.start_quad_event(), cbtn)
self.Show(True)
def start_quad_event(self):
dlg = wx.MessageDialog(self, "Test", "ABC", wx.YES_NO | wx.ICON_QUESTION)
dlg.ShowModal()
if __name__ == '__main__':
app = wx.App()
qd = QuadDash(None, title='QuadCopter Dashboard')
app.MainLoop()

The offending line is:
self.Bind(wx.EVT_LEFT_DOWN, self.start_quad_event(), cbtn)
You actually call start_quad_event() and pass the result to bind().
The correct line is:
self.Bind(wx.EVT_LEFT_DOWN, self.start_quad_event, cbtn)
Note: No parentheses. Here you actually pass the function to bind().

wxPython change mouse cursor to notify a long running operation

I am building a Python program that searches things on a remote website.
Sometimes the operation takes many seconds and I believe that the user will not notice the status bar message "Search Operation in progress".
Therefore, I would like to change the mouse cursor to highlight that the program is still waiting for a result.
This is the method I am using:
def OnButtonSearchClick( self, event ):
"""
If there is text in the search text, launch a SearchOperation.
"""
searched_value = self.m_search_text.GetValue()
if not searched_value:
return
# clean eventual previous results
self.EnableButtons(False)
self.CleanSearchResults()
operations.SearchOperation(self.m_frame, searched_value)
I tried two different approaches, both before the last line:
wx.BeginBusyCursor()
self.m_frame.SetCursor(wx.StockCursor(wx.CURSOR_WAIT))
None of them are working.
I am using KDE under GNU/Linux. This does not work under Gnome, too
Any hints? Thank you

I asked Robin Dunn, the maker of wxPython about this, and it looks like this should work, but doesn't. However, if you call the panel's SetCursor(), it DOES work or so I'm told. Here's an example you can try:
import wx
########################################################################
class MyForm(wx.Frame):
#----------------------------------------------------------------------
def __init__(self):
wx.Frame.__init__(self, None, wx.ID_ANY, "Tutorial")
# Add a self.panel so it looks the correct on all platforms
self.panel = wx.Panel(self, wx.ID_ANY)
btn = wx.Button(self.panel, label="Change Cursor")
btn.Bind(wx.EVT_BUTTON, self.changeCursor)
sizer = wx.BoxSizer(wx.HORIZONTAL)
sizer.Add(btn)
self.panel.SetSizer(sizer)
#----------------------------------------------------------------------
def changeCursor(self, event):
""""""
myCursor= wx.StockCursor(wx.CURSOR_WAIT)
self.panel.SetCursor(myCursor)
#----------------------------------------------------------------------
# Run the program
if __name__ == "__main__":
app = wx.PySimpleApp()
frame = MyForm().Show()
app.MainLoop()

How do I safely destroy a dialog window of a wxPython application?

I created a wxPython application which shows some messages on a dialog window. The dialog window is needed to be force-destroyed by the application before I click the dialog OK button. I used wx.lib.delayedresult to make the destroy call.
My code is:
import wx
dlg=wx.MessageDialog(somewindow,'somemessage')
from wx.lib.delayedresult import startWorker
def _c(d):
dlg.EndModal(0)
dlg.Destroy()
def _w():
import time
time.sleep(1.0)
startWorker(_c,_w)
dlg.ShowModal()
This can do what I desire to do while I got a error message below:
(python:15150): Gtk-CRITICAL **: gtk_widget_destroy: assertion `GTK_IS_WIDGET (widget)' failed
How do I "safely" destroy a dialog without clicking the dialog button?

It has been a while since I have used wxWidgets but I think your dlg.Destroy() may be in the wrong place. Try moving it into the main thread.
import wx
dlg=wx.MessageDialog(somewindow,'somemessage')
from wx.lib.delayedresult import startWorker
def _c(d):
dlg.EndModal(0)
def _w():
import time
time.sleep(1.0)
startWorker(_c,_w)
dlg.ShowModal()
dlg.Destroy()

I would use a wx.Timer()
import wx
########################################################################
class MyDialog(wx.Dialog):
""""""
#----------------------------------------------------------------------
def __init__(self):
"""Constructor"""
wx.Dialog.__init__(self, None, title="Test")
timer = wx.Timer(self)
self.Bind(wx.EVT_TIMER, self.onTimer, timer)
timer.Start(5000)
self.ShowModal()
#----------------------------------------------------------------------
def onTimer(self, event):
""""""
print "in onTimer"
self.Destroy()
if __name__ == "__main__":
app = wx.App(False)
dlg = MyDialog()
app.MainLoop()
See also http://www.blog.pythonlibrary.org/2009/08/25/wxpython-using-wx-timers/

My problem with dlg.Destroy() is that it is not exiting the prompt.
I have done following to exit the prompt:
def OnCloseWindow(self, e):
dial = wx.MessageDialog(None, 'Are you sure to quit?', 'Question',
wx.YES_NO | wx.NO_DEFAULT | wx.ICON_QUESTION)
ret = dial.ShowModal()
if ret == wx.ID_YES:
self.Destroy()
sys.exit(0)
sys.exit(0) will exit the prompt and move to next line.