Re: The Window expose-event with gtk_window_resize() problem:

[John Cupitt <jcupitt gmail com>]

On Tue, 6 Jul 2004 09:58:28 -0400, Tom Liu <tom liu flextrade com> wrote:
> If you set the double_buff off, you still get two expose, only thing is
> that the next expose cover's the first expose, make it looks ok.
> 
> Also,  this problem looks only happens to GtkWindow? Why we need to call
> gtk_widget_set_app_paintable for GtkWindow to print and we don't need to
> call this function for the other widgets such like eventbox etc.

I'm not sure how to fix this either, but if you change your expose
handler to this, I think it (maybe) gets a bit clearer what's going
on:

static gboolean expose(GtkWidget * widget, GdkEventExpose *event, gpointer
data)
{
       int x,y,w,h;

{
        GdkRectangle *rect;
        int i, n;

        printf( "expose bounding box: x = %d, y = %d, w = %d, h = %d\n",
                event->area.x, event->area.y,
                event->area.width, event->area.height );

        gdk_region_get_rectangles( event->region, &rect, &n );
        for( i = 0; i < n; i++ )
                printf( "expose %d: x = %d, y = %d, w = %d, h = %d\n", i,
                        rect[i].x, rect[i].y, rect[i].width, rect[i].height );
        g_free( rect );
}

  ... as before
}

If I run this, when I click on the window I see:

expose bounding box: x = 0, y = 0, w = 200, h = 200
expose 0: x = 0, y = 0, w = 200, h = 200
Debug:try102.c,29:expose:wid:200,hi:200,
expose bounding box: x = 0, y = 0, w = 220, h = 220
expose 0: x = 200, y = 0, w = 20, h = 200
expose 1: x = 0, y = 200, w = 220, h = 20
Debug:try102.c,29:expose:wid:220,hi:220,

So the first expose event you see is for the whole of the old size
window. The second expose event is actually two exposes: it's the
strip down the right and the strip across the bottom being added to
your window.

In the second expose, your gdk_window_clear() is only wiping the
strips across the bottom and down the right. I guess the
double-buffering is copying the exposed parts back to the screen, not
their bounding box.

John