Re: why i can't draw the graphic??

[James Henstridge <james daa com au>]

闄 鑳 wrote:

> hi,
>  
>  i am using the GDK to draw graphic,the compilation is ok.but it still 
> can't draw
>
> the graphic.here is my code: 

[snip]

>     Drawing_area=gtk_drawing_area_new ();
>     gtk_drawing_area_size (GTK_DRAWING_AREA (Drawing_area),640,300); 

[snip]

>     /* draw the graphic */
>     gdk_draw_rectangle(Drawing_area->window,
>                Drawing_area->style->white_gc,
>                TRUE,
>                0,0,
>                Drawing_area->allocation.width,
>                Drawing_area->allocation.height);
>
>     /*gdk_draw_line(Drawing_area->window,
>               Drawing_area->style->black_gc,0,0,100,100);
>        */ 

[snip]

> Where is the bug?
> Thanks for any help.
With a drawing area, you should connect to the expose event, and your 
handler should redraw the widget on demand.  The following section of 
the GTK+ tutorial may give you some ideas:
 http://www.gtk.org/tutorial/sec-thedrawingareawidget.html

James.

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