WxPython - trigger checkbox event while setting its value in the code

Question

Consider the following piece of code:

import wx

class MyFrame(wx.Frame):
    def __init__(self, *args, **kwds):
        wx.Frame.__init__(self, *args, **kwds)
        self.cb1 = wx.CheckBox(self, -1, "CheckBox 1")
        self.cb2 = wx.CheckBox(self, -1, "CheckBox 2")
        self.cb3 = wx.CheckBox(self, -1, "CheckBox 3")

        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(self.cb1, 0, wx.ADJUST_MINSIZE, 0)
        sizer.Add(self.cb2, 0, wx.ADJUST_MINSIZE, 0)
        sizer.Add(self.cb3, 0, wx.ADJUST_MINSIZE, 0)

        self.SetSizer(sizer)
        self.Layout()

        self.Bind(wx.EVT_CHECKBOX, self.OnCb1, self.cb1)
        self.Bind(wx.EVT_CHECKBOX, self.OnCb2, self.cb2)

    def OnCb1(self, evt):
        self.cb2.SetValue(evt.IsChecked())

    def OnCb2(self, evt):
        self.cb3.SetValue(evt.IsChecked())


if __name__ == "__main__":
    app = wx.PySimpleApp(0)
    frame = MyFrame(None, -1, "")
    app.SetTopWindow(frame)
    frame.Show()
    app.MainLoop()

Here I have 3 checkboxes bound together, so cb2 gets checked when cb1 does and cb3 gets checked when cb2 does. However, when I set the value of cb2 in OnCb1 routine, the cb2 checkbox event is not triggered, and cb3 checkbox remains unchecked. So I'd like to find a way to trigger somehow cb2 event manually to check all 3 boxes at once when checking only cb1. I'd be very grateful if anyone gives me a hint.

Answer 1

Use wx.PostEvent... like so:

class launcherWindow(wx.Frame):
    def __init__(self):
        wx.Frame.__init__(self, parent=None, title='New Window')
        #now add the main body, start with a panel
        panel = wx.Panel(self)
        #instantiate a new dropdown
        self.productDropDown = wx.ComboBox(panel, size=wx.DefaultSize, style = wx.CB_READONLY)

        #get the products and product subtypes
        self.productDict = self.getProductsAndSubtypes()

        #setup subtypes first, just in case, since onProductSelection will reference this
        self.productSubtypeDropDown = wx.ComboBox(panel, size=wx.DefaultSize, style = wx.CB_READONLY)

        #add products
        for product in self.productDict.keys():
            self.productDropDown.Append(product)

        #bind selection event
        self.productDropDown.Bind(wx.EVT_COMBOBOX, self.onProductSelection)

        #set default selection
        self.productDropDown.SetSelection(0)

        #pretend that we clicked the product selection, so it's event gets called
        wx.PostEvent(self.productDropDown, wx.CommandEvent(wx.wxEVT_COMMAND_COMBOBOX_SELECTED))

        #now add the dropdown to a sizer, set the sizer for the panel, fit the panel, etc...

    def onProductSelection(self, event):
        productSelected = self.productDropDown.GetStringSelection()
        productSubtypes = self.productDict[productSelected]

        #clear any existing product subtypes, since each product may have different ones
        self.productSubtypeDropDown.Clear()

        for productSubtype in productSubtypes:
            self.productSubtypeDropDown.Append(productSubtype)

        #select the first item by default
        self.productSubtypeDropDown.SetSelection(0)