Re: Space Bar Issue

[muppet <scott asofyet org>]

On May 23, 2006, at 11:53 PM, developer wrote:

> Sooo much trouble with setting the focus on a widget. However, I  
> did find one technique that 'almost' works. That is: $window- 
> >set_focus_child($widget); It still does not (on it's own) make the  
> widget have the focus. But after the screen loads, if I press the  
> 'TAB' key, I see the dotted rectangle appear, and now the widget  
> has the focus. That is a step in the right direction, but it still  
> doesn't solve the problem.

Here's a simple example that may illuminate things for you.

#!/usr/bin/perl -w
use strict;
use Gtk2 -init;

my $window = Gtk2::Window->new;
my $vbox = Gtk2::VBox->new;
my $button1 = Gtk2::Button->new ('one');
my $button2 = Gtk2::Button->new ('two');
my $entry = Gtk2::Entry->new;

$window->add ($vbox);
$vbox->add ($button1);
$vbox->add ($entry);
$vbox->add ($button2);

# Now that all of the widgets have been added to the widget tree and are
# attached to a toplevel, we can set the initially-focused widget.
#
# If we do nothing, gtk+ will give keyboard focus to the first widget in
# $window's widget tree.  By calling set_focus() here, we tell the  
window to
# give focus to the $entry.
$window->set_focus ($entry);
# Try commenting out that line, and note how $button1 takes the initial
# focus.  (You'll also need to comment out the set_focus_chain() line,
# or move this one after set_focus_chain()...)

# Another way to control the focus is the container's focus chain.   
By default,
# the tab key cycles through a container's child widgets in order  
from top-left
# to bottom-right.  You can alter this by manually setting the "focus  
chain".
# You can alter the order and even remove widgets from the chain.   
Note that it
# doesn't make sense to call this on $window, because $window is a  
Gtk2::Bin,
# which can have only one child.  Instead, we call it on the $vbox.   
Here,
# we'll remove $button2 from the focus chain.
$vbox->set_focus_chain ($entry, $button1);
# Try commenting out that line, and note how the tab key cycles in  
the other
# direction, and also hits $button2.


# Because $window->set_focus($child) has visibility to all children  
in the
# window, it is preferrable to set_focus_chain().


$window->signal_connect (destroy => sub { Gtk2->main_quit });
$window->show_all;
Gtk2->main;




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