[gtk-list] RE: How to redraw a widget completely?

[Patrice Fortier <Patrice Fortier aquarel fr>]

> 
> 
> > For current GTK+, your best hope is:
> > 
> >  gdk_window_clear_area (widget->window, 
> >                         widget->allocation.x,
> >                         widget->allocation.y,
> >                         widget->allocation.width,
> >                         widget->allocation.height);
> >  gtk_widget_queue_draw (widget);
> 
> 
> I think this is slightly wrong - a widget's allocation is relative to its
> parent widget's window, rather that its own (if it has one).

When you create a no_window widget, you have something like
  widget->window = widget->parent->window;

So the above code is correct.

> And it won't work for widgets which have extra child windows,
> e.g. clist, hscale/vscale, hscrollbar/vscrollbar.

why?
I can't see any problem with scale or scrollbar.
It seems that there is a bug in clist.



> void
> editor_refresh_widget (GtkWidget *widget)
> {
>   GtkWidget *parent;
>   gint x, y, w, h;
>   GdkGC *gc;
> 
>   if (!GTK_WIDGET_DRAWABLE (widget))
>     return;
> 
>   x = widget->allocation.x;
>   y = widget->allocation.y;
>   w = widget->allocation.width;
>   h = widget->allocation.height;
> 
>   if (widget->parent)
>     {
>       gdk_window_clear_area (widget->parent->window, x, y, w, h);
>       clear_child_windows (widget->parent->window, x, y, w, h);
>     }
>   else
>     {
>       gdk_window_clear (widget->window);			 
>       clear_child_windows (widget->window, -1, -1, -1, -1);
>     }
> 
>   /* queue_draw doesn't work with a clist. */
>   /*gtk_widget_queue_draw (widget);*/
>   gtk_widget_draw (widget, NULL);
>   gtk_widget_draw_children (widget);
> }


> /* This clears all child windows which fall within the given rectangle.
>    If the rectangle width is -1, then all children are cleared. */
> static void
> clear_child_windows (GdkWindow *window, gint x, gint y, gint w, gint h)
> {
>   GList *children;
>   GdkWindow *child_window;
>   gint win_x, win_y, win_w, win_h;
>   XWindowAttributes xwa;
> 
>   children = gdk_window_get_children (window);
>   while (children)
>     {
>       child_window = children->data;
>       gdk_window_get_position (child_window, &win_x, &win_y);
>       gdk_window_get_size (child_window, &win_w, &win_h);
> 
>       if (w == -1
> 	  || !(win_x >= x + w || win_x + win_w <= x
> 	       || win_y >= y + h || win_y + win_h <= y))
> 	{
> 	  /* We need to make sure this is not an InputOnly window, or we get
> 	     a BadMatch. CList uses InputOnly windows - for resizing columns.*/
> 	  XGetWindowAttributes (GDK_DISPLAY (),
> 				GDK_WINDOW_XWINDOW (child_window), &xwa);
> 	  if (xwa.class != InputOnly)
> 	    {
> 	      gdk_window_clear (child_window);
> 	      clear_child_windows (child_window, -1, -1, -1, -1);
> 	    }
> 	}
>       children = children->next;
>     }
>   g_list_free (children);
> }
> 
> 
> 
> Also, gtk_widget_queue_draw() doesn't redraw a GtkCList properly - the
> column titles and the scrollbars are not drawn.
> I have to use both of these:
> 
>   gtk_widget_draw (widget, NULL);
>   gtk_widget_draw_children (widget);
> 
> Does this matter? Is this a bug in CList?

Checking the sources of clist, yes this is a bug in clist.

I tink you clear way to many windows :). Maybe this is because
of the clist bug.


Lokh.