Re: How to emit predefined signals in gtkmm.

[Chris Vine <chris cvine freeserve co uk>]

On Sunday 05 November 2006 11:38, German Diago Gomez wrote:
> Hello. My question is quite simple, but I haven't been able to find such
> thing in the gtkmm documentation.
>  I'm using cairo and a Gtk::DrawingArea derived class to draw inside a
> window in Gtk.
> The problem is that I get data from three entries in a function, and
> after that, I want to update the drawing of the area when a button is
> clicked. To update the drawing, if I'm right, I must do it from the
> on_expose_event overriden function in the Gtk::DrawingArea derived
> class. Since I want to update immediatly after calling the slot
> connected to signal_clicked() in my button, I must emit a signal
> signal_expose_event() if I'm not wrong.
>   I looked at the documentation and I realized that
> signal_expose_event() doesn't return a sigc::signal but a proxy object.
> How can I emit a signal so that on_expose_event is called after clicking
> the button from the slot called for the button?

To generate an expose event, use Gtk::Widget::queue_draw() and 
Gtk::Widget::queue_draw_area() (or if you want to go down to the gdk level, 
you can use Gdk::Window::invalidate_region() directly).

Chris