Re: gtk-perl tutorial and help

[Andy Ford <andy ford telindus co uk>]

Thanks Scott

I fumbled my way through and realised it was not 'realized'!!
Your explanation certainly helps - thanks for your time

Regards

Andy

On Mon, 2003-01-20 at 14:03, muppet wrote:
> Andy Ford wrote:
>
> > When I run this, I get the following error message...
> >
> > 'window is not of type Gtk::Gdk::Window '
> >
> > The error message was generated from the code..
> > ....create_from_xpm_d( $window->window,$style,@xpm_data );
>
> in order to use a GdkWindow, the GdkWindow must exist.  the GdkWindow 
> corresponds exactly to the actual XWindow, which doesn't exist on the X 
> server until the XWindow has been created or "realized"; you typically 
> realize a GtkWidget's GdkWindow by calling gtk_widget_show -- which 
> calls XMapWindow.
>
> however, while calling show on a child window marks it to be shown with 
> the parent, calling show on  a toplevel (as you are doing) causes the 
> whole thing to show up right then ---- since you aren't finished setting 
> it up, this causes unwanted layouts and freaky visual nastiness.
>
> to force the creation of the GdkWindow without putting the window on the 
> screen yet, you must "realize" the widget separately before showing it 
> by calling gtk_widget_realize (normally gtk_widget_show calls 
> gtk_widget_realize for you).[1]
>
> > $window = new Gtk::Window( 'toplevel' );
> > $style = $window->get_style()->bg( 'normal' );
>
> $window->realize;
>
> > ($pixmap, $mask ) = Gtk::Gdk::Pixmap->create_from_xpm_d(
> > $window->window,$style,@xpm_data );
>
>
> now $window->window is valid to use.
>
>
> another alternative is to create the pixmap without a window, using 
> gdk_pixmap_colormap_create_from_xpm_d, a la
>
> ($pixmap, $mask) = new Gtk::Gdk::Pixmap::colormap_create_from_xpm_d ( 
> undef, $window->get_colormap, $style, @xpm_data );
>
> note the fact that we're using a colormap rather than a GdkWindow as the 
> reference drawable.  this allows you to do complete setup of your window 
> hierarchy *before* the window is realized.  (in fact, you don't have to 
> call realize.  :-)
>
> [1] for a little more correct explanation of realizing, mapping, and 
> showing, see the GGAD: 
> http://developer.gnome.org/doc/GGAD/z57.html#SEC-REALIZINGSHOWING