java-gnome-developer

[Java-gnome-developer] DrawingArea or Drawable

[Breizh M. S. <fra...@bm...>]

Hi Everybody !

I am trying to use a DrawingArea but I do not know how to. Is there any 
documentation about it somewhere ?
This the code I am trying

        int width,height;
        org.gnu.gdk.Window GdkWindow = drawingarea.getParentWindow();
        width = GdkWindow.getWidth();
        height = GdkWindow.getHeight();
        GdkWindow.drawLine(0,0,100,100);
       
        drawingarea.setBackgroundColor(StateType.ACTIVE,Color.BLACK);   
        drawingarea.show();
        window.showAll();

But there is nothing to display. What's wrong ?

Thanks
Fanch.

Re: [Java-gnome-developer] DrawingArea or Drawable

[Adam J. <ajo...@re...>]

Breizh Micro Services wrote:
> Hi Everybody !
>
> I am trying to use a DrawingArea but I do not know how to. Is there any 
> documentation about it somewhere ?
> This the code I am trying
>
>         int width,height;
>         org.gnu.gdk.Window GdkWindow = drawingarea.getParentWindow();
>         width = GdkWindow.getWidth();
>         height = GdkWindow.getHeight();
>         GdkWindow.drawLine(0,0,100,100);
>        
>         drawingarea.setBackgroundColor(StateType.ACTIVE,Color.BLACK);   
>         drawingarea.show();
>         window.showAll();
>
> But there is nothing to display. What's wrong ?
>
> Thanks
> Fanch.
>
>
> _______________________________________________
> java-gnome-developer mailing list
> jav...@li...
> https://lists.sourceforge.net/lists/listinfo/java-gnome-developer
>   

You're going to need to attach an ExposeListener to the Drawing area and 
do the drawing in there. You'll also need to check to make sure that the 
event isn't of type NO_EXPOSE. Something like the following should work:

drawingArea.addListener(new ExposeListener(){
    public boolean exposeEvent(ExposeEvent event){
        if(event.isOfType(ExposeEvent.Type.NO_EXPOSE)){
            return false;
        }

        // Do your drawing here
    }
});


hope this helps :)