How can I make wxWidgets controls accept middle-button clicks?

Question

I have a scenario in which I would like some wxWidgets controls to respond to middle-button mouse clicks, behaving in exactly the same way as they normally would for a left click, except that I should be able to tell it's a middle click and do something different in my application.

Specifically, I am working with buttons and sliders, and want the buttons to be pressable and the slider to be draggable with the middle button. I'm in Windows (and that's the only platform I care about), in case that makes a difference.

After poking through the wx docs a bit I didn't find any way to set which mouse buttons a control listens to. So, my first idea was to write an event handler that captures middle-button events, translates them to the corresponding left-button events, and tells wx to process them:

void OnMouseEvent(wxMouseEvent & wxevent)
{
    wxMouseEvent wxeventTranslated = wxevent;

    if (wxevent.MiddleDown())
    {
        wxeventTranslated.SetEventType(wxEVT_LEFT_DOWN);
    }
    else if (wxevent.MiddleUp())
    {
        wxeventTranslated.SetEventType(wxEVT_LEFT_UP);
    }
    else
    {
        return;
    }

    m_pWxbutton->ProcessWindowEvent(wxeventTranslated);
}

(here m_pWxbutton is the wxButton where the events are registered). It didn't work: the mouse event handler is called, but I never get a wxEVT_COMMAND_BUTTON_CLICKED event, nor does the button enter the "pressed" visual state in the GUI. I also tried a version where I changed the event type on the passed-in event and then called Skip(), but that had the same result.

Admittedly for buttons it would be easy to just detect the click myself, but I am hoping to get this to work for sliders as well, and I don't relish the idea of reimplementing all the mouse logic for those. :)

How can I translate mouse events and get them to behave like native GUI events? Or, is there a completely different approach I should try?

VZ. VZ. · Accepted Answer · 2012-09-15T10:57:14

You can't modify the behaviour of the standard controls like this -- this is why they're standard. You can, of course, use custom button-like controls handling the mouse in any way you want but there is no portable way to modify the standard controls to do what you want, at best you can use platform-specific code and on some platforms this could be completely impossible.

How can I make wxWidgets controls accept middle-button clicks?

1 Answers