Re: dragging text on Gnome2Canvas -- answered

[zentara <zentara1 sbcglobal net>]

On Tue, 24 Oct 2006 12:19:17 -0400
zentara <zentara1 sbcglobal net> wrote:

> Hi, I have a glitch here which I can't explain.

Well I dissected the Gnome2::Canvas demo, and found
out that text items need to be in a group, and that you
signal connect and drag the group. 

> #!/usr/bin/perl
> use warnings;
> use strict;
> use Gtk2 '-init';
> use Gnome2::Canvas;
>
> my ( $dragging, $last_x, $last_y ); 
>
> my $mw = Gtk2::Window->new;
>    $mw->signal_connect( destroy => sub { exit } );
>
>    my $vbox = Gtk2::VBox->new( 0, 0 );
>    $mw->add($vbox);
>
> my $canvas = Gnome2::Canvas->new_aa();
>    $vbox->pack_start( $canvas, 1, 1, 0 );
>    $canvas->set_size_request( 300, 300 );
>    $canvas->set_scroll_region( 0, 0, 300, 300 );
>
>    my $quit = Gtk2::Button->new("Quit");
>    $quit->signal_connect( clicked => sub { exit } );
>    $vbox->pack_start( $quit, 0, 0, 0 );
>
> $mw->show_all();
>
> place_objects_on_canvas();
>
> Gtk2->main();
>
> ##########################################################
>
> sub place_objects_on_canvas {
>    my $root = $canvas->root();
>
>    for my $p (
>        [ 50,  50,  "green" ],
>        [ 50,  250, "orange" ],
>        [ 250, 50,  "yellow" ],
>        [ 250, 250, "blue" ]
>      )
>    {
>
>        my ( $x, $y, $color ) = @$p;
>
>        # Put a circle on the graph
>        my $item = Gnome2::Canvas::Item->new(
>            $root, "Gnome2::Canvas::Ellipse",
>            x1            => $x - 16,
>            y1            => $y - 16,
>            x2            => $x + 16,
>            y2            => $y + 16,
>            fill_color    => $color,
>            outline_color => "black",
>       );

# add group
      my $group = Gnome2::Canvas::Item->new ($root,
                    'Gnome2::Canvas::Group', x => $x,                                   
                                                                y => $y);       
>       my $text = Gnome2::Canvas::Item->new ($group,  'Gnome2::Canvas::Text',
>                                  text => 'Z',
>                                  font => 'arial 30',
                                   x => 0 ,   # 0 position in group
                                   y => 0 ,
>                                  anchor => 'w', 
>                                  fill_color => 'black');
>
>
>
>        # Make them movable
        $item->signal_connect( "event", \&item_move );
        $group->signal_connect( "event", \&item_move );
>    
>    }
> }
> ######################################################
> sub item_move {
>    my ( $item, $event ) = @_;
>     print "$item $event\n";
>
>    if ( $event->type eq "button-press" ) {
>        $item->raise_to_top();
>        $last_x   = $event->x;
>        $last_y   = $event->y;
>        $dragging = 1;
>    }
>    elsif ( $event->type eq "motion-notify" ) {
>        if ($dragging) {
>            my $new_x = $event->x;
>            my $new_y = $event->y;
>
>            $item->move( $new_x - $last_x, $new_y - $last_y );
>            $last_x = $new_x;
>            $last_y = $new_y;
>        }
>    }
>    elsif ( $event->type eq "button-release" ) {
>        $dragging = 0;
>    }
>
> return 0;
> }
> __END__
>
> -- 
> I'm not really a human, but I play one on earth.
> http://zentara.net/japh.html
> _______________________________________________
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> gtk-perl-list gnome org
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-- 
I'm not really a human, but I play one on earth.
http://zentara.net/japh.html