Button-Binding

[Alex]

Deal all!

I continue my experiments with SDL. I found some old thread somewhere and
now I have a button-like image that switches its appearance when I hover
over it (with the mouse).

Here are the questions:
a) Is the code attached the recommended way to do it or should it be done in
another fashion?
b) I would like to add an action, when someone clicks the button. In
Tk-terminology, this would be a callback. Any suggestions on how I should do
this?

Best regards,
Alex

[code]
#!perl

package My::SimpleButton;

use strict;
use warnings;
use SDL;
use SDLx::Rect;
use Data::Dumper qw/Dumper/;

=head1

=cut

sub new {
    my ($class,@params) = @_;
    my $self = {};
    bless($self,$class);
    for(qw(ID APP X Y IMG IMGHV IMGPRESSED)){
        $self->{$_} = shift(@params);
    }   
    $self->{HV} = 0;
    
    $self->draw($self->{IMG});
    
    return($self);
}



sub draw{
    my ($self, $img) = @_;
    
    my $frame_rect = SDLx::Rect->new(0, 0, $img->width(), $img->height());
    my $dest_rect = SDLx::Rect->new(
        $self->{X},
        $self->{Y},
        $img->width(),
        $img->height(),
    );

    $self->{APP}->blit_by($img, [0, 0, $img->width(), $img->height()], [
        $self->{X},
        $self->{Y},
        $img->width(),
        $img->height(),
    ]);
    $self->{APP}->update();
    
    return 1;
}

sub check{
    my ($self,$mx,$my,$event) = @_;

    my $img = $self->{IMG};
    
    #Hover - Effekt
    if( $mx > $self->{X} &&  
        $mx < ($self->{X}+ $img->width)  && 
        $my > $self->{Y}    &&   
        $my < ($self->{Y}+ $img->height) ){

        if( !$self->{HV} ) {
            $self->{HV} = 1;
            $self->draw($self->{IMGHV});
        }

    } else {
        if($self->{HV}) {
            $self->{HV}=0; 
            $self->draw($self->{IMG});
        }
        return 0;

    }
    
    return;
}

=head1 CREDITS

c.f. L<http://www.perl-community.de/bat/poard/thread/7847>

=cut

1; # /My::SimpleButton

use SDL;
use SDLx::App;
use SDL::Event;
use SDL::Events;
use SDLx::Surface;
use SDL::Color;

my $app = SDLx::App->new(
    w => 640,
    h => 400,
    exit_on_quit => 1,
);
$app->add_event_handler( \&quit_event );
$app->add_event_handler( \&mnouseover );

my $img = SDLx::Surface->load( 'images/blueOpera_1.png' );
my $img2 = SDLx::Surface->load( 'images/blueOpera_2.png' );
my $img3 = SDLx::Surface->load( 'images/redOpera_2.png' );

my $SimpleButton = My::SimpleButton->new(1, $app, 65, 25, $img, $img2,
$img3);

$app->run();

sub quit_event {
    #The callback is provided a SDL::Event to use
    my $event = shift;
    
    #Each event handler also returns you back the Controller call it
    my $controller = shift;
    
    #Stopping the controller for us will exit $app->run() for us
    $controller->stop if $event->type == SDL_QUIT;
} # /quit_event


sub mnouseover {
    #The callback is provided a SDL::Event to use
    my $event = shift;
    
    #Each event handler also returns you back the Controller call it
    my $controller = shift;
    
    if( $event->type == SDL_MOUSEMOTION ) {
        my $click = $SimpleButton->check($event->motion_x,
$event->motion_y,$event);
    }
} # /mnouseover


exit(0);
[/code]