Re: How to Center Dialogs or Popups Over Any Widget (Source Code Included)

[Havoc Pennington <hp redhat com>]

Paul Serice <serice bigfoot com> writes:
> /*
>  * One of my biggest complaints about Gtk+-based programs is that
>  * popups never popup centered over the correct window.  At best they
>  * come up in the middle of the display or over the mouse.  More
>  * commonly, they quietly come up in some random location on the
>  * display.
>  * 
>  * The correct way, IMHO, to popup a dialog is to place it in the
>  * center of the window responsible for popping it.  The fact that it
>  * is centered over the window tells me that, yes, this pop up is part
>  * of the program underneath it.  When a dialog popups up over a
>  * different program, it is confusing because the program underneath
>  * the popup has no relationship with the popup itself.
>  * 
>  * What follows is an example of how to popup a dialog centered over
>  * any widget including a GTK_WINDOW widget.  It also shows how to
>  * raise an iconified popup to the same place where it was originally
>  * iconified.
>  * 
>  * If you find a better way of doing this, please let me know.
>  *

GTK+ 2.0 supports this natively with GTK_WIN_POS_CENTER_ON_PARENT
(parent being the transient parent from set_transient_for()).
So that will be a better way in the future.

>     /*
>      * Either I'm not doing something right or I'm not thinking about
>      * something right or . . . , but it seems to me that
>      * "gtk_widget_show()" should raise iconified windows.  It does
>      * not.  So, we have to also call gdk_window_show().
>      */
>     gdk_window_show(dialog->window);

gtk_widget_show() simply realizes and maps the window if it isn't, it
does nothing if it already is (where "map" refers to the GTK+ flag,
not the X state). gdk_window_show() will affect the X state even if
GTK flags the widget already mapped.

GTK+ 2.0 will likely have gtk_window_set_iconified(window, FALSE) or
the like, and an "iconified" signal. (If you're not catching the theme
here, basically there's no reason you should have to do all these
weird undocumented hacks, and GTK+ should support an official nice way
to do them, so 2.0 will support nice ways.) Also we wanted to add a
present_window() function that deiconifies and raises the window, and
maybe once we have the proper WM extensions will make sure the window
is on the current desktop. present_window() will be the right thing if
you want to bring an existing dialog forward to the user's attention.
 
>     /*
>      * Show.
>      */
>     gtk_widget_show(window_manager_decides_button);
>     gtk_widget_show(center_over_display_button);
>     gtk_widget_show(center_over_pointer_button);
>     gtk_widget_show(center_over_widget_button);
>     gtk_widget_show(label);

gtk_widget_show_all() would save you a lot of typing. ;-)

Havoc