wxPython panel SetBackgroundColour on button event

Question

I am trying to add a feature to a calculator i have made with wxpython, i want there to be a button , that when clicked changes the background colour (the panel). To show you my code i have made a smaller program, that should only change colour, and even in this one i get the same outcome: the background colour doesn't change, nothing happens when i click the button, and i dont even receive any errormessahe.Actually, the calculator does change colour, but not in the way i want it to, it only changes the colour of the text (a wx.StaticText), and it's not really meant to do that. Anyway, here is the code :

import wx

class calc(wx.Frame):


    def __init__(self,parent,id):
        wx.Frame.__init__(self,parent,id,"Calculator",size=(400,400))
        global panel
        panel=wx.Panel(self)
        a=wx.Button(panel,label="GO",pos=(100,100),size=(50,50))
        self.Bind(wx.EVT_BUTTON, self.change, a)
    def change(self,event):
        panel.SetBackgroundColour("red")






if __name__=="__main__":
    app=wx.App(False)
    frame=calc(parent=None,id=-1)
    frame.Show()
    app.MainLoop()

when i run this, the frame with the button show up, and when i click on the button, nothing happens!! Does anybody know what is wrong with this? Thanks in advice!!!

Answer 1

While your code worked for me on Xubuntu 14.04, wxPython 2.8.12 and Python 2.7, I went ahead and rewrote it slightly to remove the global and clean it up a bit:

import wx

class calc(wx.Frame):

    def __init__(self):
        wx.Frame.__init__(self, None, title="Calculator", size=(400,400))
        self.panel = wx.Panel(self)

        a = wx.Button(self.panel, label="GO", pos=(100,100), size=(50,50))
        self.Bind(wx.EVT_BUTTON, self.change, a)

    def change(self,event):
        self.panel.SetBackgroundColour("red")
        self.Refresh()  # for windows

if __name__=="__main__":
    app = wx.App(False)
    frame = calc()
    frame.Show()
    app.MainLoop()

This also works for me.