Re: How to create a popup?

[muppet <scott asofyet org>]

On Saturday, November 22, 2003, at 10:19 AM, Thomas Bayen wrote:

> * How can I make that my popup behaves like a real one?

i would love to know.  for a few years now, i've had a gtk-perl 
date-combo that just doesn't pop down correctly.  i'm missing something 
simple-yet-important.  but i've looked at it a lot and can give you 
some hints, so maybe you'll figure out what i've missed.


> For example if I move my main window around with the mouse the popup 
> stays on the old screen position :-(

erm, most popups go away when you click outside of them.  think of 
optionmenus, menus in general, and comboboxen -- they're open until you 
click anywhere outside them, which means you can't grab the window 
border without the popup popping down.

to get this popup-moves-when-the-parent-moves behavior, you'd have to 
connect to something that tells you the window has been moved so you 
can move your child --- the only way to move two together (unless 
you're a window manager) is to have one be a child of the other, which 
popup windows aren't.


> if I use "$self->{win}->set_property('type','popup')" the input focus 
> does not go into the popup widget but stays in the main window.

you have to explicitly set the focus to be in that new popup window.

> If I make it modal, it gets the focus, but I can't click into the main 
> window any more to close the popup (like a menu popup would).

you don't want it to be modal, you want it to grab the pointer; then 
you test to see if you get an event outside the popup, and when you do, 
close the popup.  (that's what the code in gtkcombo.c appears to do.)


> Is there any simple (perl or C) example about creating my own popups?

not that i know of.  i've been looking for some time so i can make the 
cellrenderer_date sample work correctly; before that, i was desperately 
trying to figure how to get a date combo's popup to popdown properly.  
the code in gtkcombo.c is a little labyrinthine and unhelpful in that 
respect, unfortunately, and testing out code that works with pointer 
grabs can be nightmarish if you don't have a second machine handy to 
log in and kill the app with the lost grab.


>   Can't locate object method "get_root_window" via package ...
>
> Is this method not implemented, if it is how can I call it or how can 
> I find out the root coordinates of my widget in another way?

erm... well, no, that's not bound.  it's a 2.2 method that appears to 
have slipped through the cracks.  GtkWidget.xs was one of the first 
files created in gtk2-perl-xs, and came from the gtkwidget.h in my 
2.0.6 installation which doesn't have that method and a few others.

this will get you going until i put it in cvs:

Index: xs/GtkWidget.xs
===================================================================
RCS file: /cvsroot/gtk2-perl/gtk2-perl-xs/Gtk2/xs/GtkWidget.xs,v
retrieving revision 1.38
diff -u -r1.38 GtkWidget.xs
--- xs/GtkWidget.xs     17 Nov 2003 02:43:10 -0000      1.38
+++ xs/GtkWidget.xs     23 Nov 2003 07:43:25 -0000
@@ -828,10 +828,13 @@
        GdkAtom     selection


-#GdkDisplay* gtk_widget_get_display (GtkWidget *widget)
-GdkDisplay *
-gtk_widget_get_display (widget)
-       GtkWidget * widget
+GdkDisplay * gtk_widget_get_display (GtkWidget * widget)
+
+GdkWindow * gtk_widget_get_root_window (GtkWidget * widget)
+
+GdkScreen * gtk_widget_get_screen (GtkWidget * widget)
+
+gboolean gtk_widget_has_screen (GtkWidget * widget);

 #endif


> * I use the "allocation" function to get the coordinates of the 
> widget. I can not find documentation to this function. I found it only 
> with indirect mention. If this is a "documentation bug" I want to 
> report it here...

it's an accessor for a member variable, not a *real* function.  the 
allocation describes how much space was actually allocated to the 
widget, which asked for the amount of space in the requisition.  i have 
no idea what the x and y in the allocation actually are -- i  presume 
that they are the coordinates of the widget's origin relative to its 
parent, but i can't prove that.


> sub callback_openpopup{
>   my($self)= _;
>   $self->{win}->destroy if defined $self->{win};

why destroy it if it already exists?  usually you'd want just to show 
it again to keep from having to re-create it.  (but destroying works, 
just a thought)

>   $self->{win}=Gtk2::Window->new;
>   # What's this for?!?:
>   # $self->{win}->set_property('type','popup');

type is a construct-only property.  you want instead to do

   $self->{win} = Gtk2::Window->new ('popup')

>   $self->{win}->set_destroy_with_parent(1);
>   $self->{win}->set_decorated(0);

these are not necessary if you create the window correctly.


>   $self->{win}->set_default_size(400,200);
>   # find the right coordinates:
>   my($winx,$winy)=$self->get_toplevel->get_position;
>   my($x,$y)=($self->allocation->x,$self->allocation->y);

allocation doesn't do what you want it to do here.  find the upper left 
corner of the GdkWindow associated with the widget, and use *that* for 
x and y.

  my ($x, $y) = $self->window->get_origin;

>   $self->{win}->move($winx+$x,$winy+$y);
>   my $search=Gtk2::RecordSearch->new();
>   $self->{win}->add(my $f=Gtk2::Frame->new());
>   $f->set_shadow_type('etched-out');
>   $f->add($search);
>   $self->{win}->show_all;
> }



--
muppet <scott at asofyet dot org>