Re: Moveable Goocanvas::Widgets

[Damon Chaplin <damon karuna eclipse co uk>]

On Sun, 2009-02-22 at 13:51 +0100, Robert Gründler wrote:

> This resulted in the next workaround, listening to the motion notify 
> event on the canvas itself, handling the dragging logic in there, which 
> brought me to a point where i'm really stuck now. The 
> motion_notify_event from the Goocanvas::Canvas itself is dispatched 
> correctly, even if the mouse is over a child Widget. However, i'm not 
> receiving the signal anymore as soon as the left mouse button is clicked 
> on a widget on the canvas...
> 
> _canvas->signal_motion_notify_event().connect(sigc::mem_fun(*this, 
> &MyWindow::on_canvas_motion_notify_event, false);
> 
> bool MyWindow::on_canvas_motion_notify_event(GdkEventMotion* event) { // 
> <-- not called when the mouse button has been pressed on a widget on the 
> canvas
>   std::cout << "motion detected" << std::endl; 
> }

It might be better to connect to the "event" signal of the embedded
widgets. That way you should get all the events aimed at the widget
before anything gets a chance to interfere.

Also, make sure you call gtk_widget_set_events() on the embedded widget
with all the types of events you need.

Damon