GTK+ Forums

ichbinsnur · Joined: 16 Mar 2008 Posts: 4

Hi,
i have a very hard problem with a drawing area and i couldn't find a solution for that problem.
I created 2 (dialog) windows.
The first one contains a drawing area. Inside of the drawing area i want to draw some circles. This circles are showing the state of some lamps (light on=red filled circle, or light off=black filled circle).
The state of the lamps should be updated every 100ms.
The second window contains some dialog items like buttons, sliders and so on for configuration.
I'm calling the function:
gtk_widget_queue_draw_area( drawingArea,
0,0,
drawingArea->allocation.width,
drawingArea->allocation.height);
every 100ms.

inside of the expose event function i'm drawing the images with:

if( light == ON )
gdk_draw_pixbuf(widget->window,
drawGc,
imageRed,
0,0,
xpos,ypos,
-1,-1,
GDK_RGB_DITHER_NONE,
0,0);
else
gdk_draw_pixbuf(widget->window,
drawGc,
imageBlack,
0,0,
xpos,ypos,
-1,-1,
GDK_RGB_DITHER_NONE,
0,0);

this works fine, but after some minutes the drawed circles and the dialog items (buttons a.s.o.) disapears. So i have 2 Windows containing nothing.
Is there anybody who can help me?

ichbinsnur · Joined: 16 Mar 2008 Posts: 4

Seems, that it is not possible to draw items in a frequently way..
Is there nobody, who knows, how to draw in a drawing area?
nothing of the examples i found works.

mhydra · Joined: 05 Mar 2008 Posts: 3

It is very easy. Just place all your draw functions in the "expose" event for the GtkDrawing area and everything will be fine.