wxPython: Calling an event manually

Question

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

Answer 1

You mean you want to have an event dispatch?

::wxPostEvent void wxPostEvent(wxEvtHandler *dest, wxEvent& event)

In a GUI application, this function posts event to the specified dest object using wxEvtHandler::AddPendingEvent. Otherwise, it dispatches event immediately using wxEvtHandler::ProcessEvent. See the respective documentation for details (and caveats).

Include files

<wx/app.h>

wxPython API docs

Answer 2

I think you want wx.PostEvent.

There's also some info about posting events from other thread for long running tasks on the wxPython wiki.

Answer 3

Old topic, but I think I've got this figured out after being confused about it for a long time, so if anyone else comes through here looking for the answer, this might help.

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 to someone.