wx.Python: Passing control between multiple panels

Question

I\'m a newbie to wxPython, and have researched similar questions, but can\'t specifically find an answer to my question. I\'m creating two panels with a splitter. Each panel has

Answer 1

A clean design can be achieve using pubsub:

import wx
import wx.grid as gridlib
from wx.lib.pubsub import pub

#import pyodbc

class RightPanel(wx.Panel):
    """"""

    def __init__(self, parent):
        """Constructor"""
        wx.Panel.__init__(self, parent=parent)        

        grid = gridlib.Grid(self)
        grid.CreateGrid(5,5)

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(grid, 0, wx.EXPAND)
        self.SetSizer(sizer)

        pub.subscribe(self.changeColourEvent, "MOOD_CHANGE")


    def changeColourEvent(self, value):
        self.SetBackgroundColour(value)
        self.Refresh()


class LeftPanel(wx.Panel):
    """"""

    def __init__(self, parent):
        """Constructor"""
        wx.Panel.__init__(self, parent=parent)  

        self.create_controls()
        self.SetBackgroundColour("grey")


    def create_controls(self):

        self.h_sizer = wx.BoxSizer(wx.HORIZONTAL)
        self.v_sizer = wx.BoxSizer(wx.VERTICAL)

        self.bbutton = wx.Button(self, label="Got dem blues?!")
        self.bbutton.Bind(wx.EVT_BUTTON, self.blues_button_pressed)     

        self.hbutton = wx.Button(self, label="Happy happy!")
        self.hbutton.Bind(wx.EVT_BUTTON, self.happy_button_pressed)     

        self.v_sizer.Add(self.bbutton, 0)
        self.v_sizer.Add(self.hbutton, 0)

        self.v_sizer.Add(self.h_sizer, 0, wx.EXPAND)
        self.SetSizer(self.v_sizer)


    def blues_button_pressed(self,event):
        pub.sendMessage("MOOD_CHANGE", value = "blue")        


    def happy_button_pressed(self,event):
        pub.sendMessage("MOOD_CHANGE", value = "yellow")        


class MyForm(wx.Frame):

    def __init__(self):
        wx.Frame.__init__(self, None, wx.ID_ANY, "DB Viewer",size=(350, 250))

        splitter = wx.SplitterWindow(self)
        leftP = LeftPanel(splitter)
        rightP = RightPanel(splitter)

        splitter.SplitVertically(leftP, rightP)
        splitter.SetMinimumPaneSize(20)

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(splitter, 1, wx.EXPAND)
        self.SetSizer(sizer)

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

The advantage that this sort of approach brings is that it means that no pane is dependent on the design of any other pane. You can see that neither MyForm nor RightPanel needs to know whether LeftPanel is deciding that it's time to change colour based on a button or a checkbox or any other mechanism. In this code, MyForm cares only about instantiating two panes. It does not get tangled up in the logic of what goes between them.

It's also readily extensible in the type of information that objects (in this case, panes) can pass to each other.

It also allows for other elements to be added to the design that care about the same kinds of thing (in my example case, mood changes) without impacting the code of anything other than themself.