wxPython: Calling an event manually

Question

How can I call a specific event manually from my own code?

Answer 1

To manually post an event, you can use:

self.GetEventHandler().ProcessEvent(event)

(wxWidgets docs here, wxPython docs here)

or

wx.PostEvent(self.GetEventHandler(), event)

(wxWidgets docs, wxPython docs)

where event is the event you want to post. Construct the event with e.g.

wx.PyCommandEvent(wx.EVT_BUTTON.typeId, self.GetId())

​​​​​​if you want to post a EVT_BUTTON event. Making it a PyCommandEvent means that it will propagate upwards; other event types don't propagate by default.

You can also create custom events that can carry whatever data you want them to. Here's an example:

myEVT_CUSTOM = wx.NewEventType()

EVT_CUSTOM = wx.PyEventBinder(myEVT_CUSTOM, 1)

class MyEvent(wx.PyCommandEvent):

    def __init__(self, evtType, id):

        wx.PyCommandEvent.__init__(self, evtType, id)

        myVal = None

    def SetMyVal(self, val):

        self.myVal = val

    def GetMyVal(self):

        return self.myVal

(I think I found this code in a mailing list archive somewhere, but I can't seem to find it again. If this is your example, thanks! Please add a comment and take credit for it!)

So now, to Post a custom event:

event = MyEvent(myEVT_CUSTOM, self.GetId())

event.SetMyVal('here is some custom data')

self.GetEventHandler().ProcessEvent(event)

and you can bind it just like any other event

self.Bind(EVT_CUSTOM, self.on_event)

and get the custom data in the event handler

def on_event(self, e):

    data = e.GetMyVal()

    print 'custom data is: {0}'.format(data)

Or include the custom data in the event constructor and save a step:

class MyEvent(wx.PyCommandEvent):

    def __init__(self, evtType, id, val = None):

        wx.PyCommandEvent.__init__(self, evtType, id)

        self.myVal = val

etc.

Hope this is helpful