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#!/usr/local/bin/perl -w
use Tk;
use strict;
use Tk::DragDrop;
use Tk::DropSite;

Tk::DragDrop->import(@ARGV);
Tk::DropSite->import(@ARGV);

my $top = MainWindow->new();
$top->Button('-text' => "Quit", '-command' => ['destroy',$top])->pack;

my $f = $top->Frame->pack;

my $sun = $f->Label(-relief => 'ridge','-text' => "Sun")->pack(-side => 'left');
$sun->DragDrop(-event => '<B1-Motion>', -text => 'Sun', -sitetypes => [qw(Sun)]);

my $either = $f->Label(-relief => 'ridge','-text' => "Either")->pack(-side => 'left');
$either->DragDrop(-event => '<B1-Motion>', -text => 'Either', -sitetypes => [qw(Local Sun)]);

my $loc = $f->Label(-relief => 'ridge','-text' => "Loc")->pack(-side => 'right');
$loc->DragDrop(-event => '<B1-Motion>', -text => 'Local', -sitetypes => [qw(Local)]);

my $canvas = $top->Canvas(-width => 200, -height => 200,
                          -relief => 'groove', -borderwidth => 3)->pack;

my $sid = $canvas->create('oval',0,0,10,10,-fill => 'red');
my $lid = $canvas->create('oval',0,0,10,10,-fill => 'blue');

$canvas->DropSite(-motioncommand => [\&Motion,$canvas,"Sun",$sid],
                       -dropcommand   => [\&Drop,$canvas,"Sun",$sid],
                       -droptypes => 'Sun' );
$canvas->DropSite(-motioncommand => [\&Motion,$canvas,"Loc",$lid],
                  -dropcommand   => [\&Drop,$canvas,"Sun",$lid],
                  -droptypes => 'Local' );

MainLoop;

sub Motion
{
 my ($canvas,$type,$id,$x,$y) = @_;
 $canvas->coords($id,$x-5,$y-5,$x+5,$y+5);
 # printf "$type x=%3d y=%3d\n",$x,$y;
}

sub Drop
{
 my ($canvas,$type,$id,$seln,$x,$y) = @_;
 Motion($canvas,$type,$id,$x,$y);
 my $text = $canvas->SelectionGet(-selection => $seln);
 my $col  = $canvas->itemcget($id,'-fill');
 $canvas->create('text',$x,$y,-text => $text, -justify => 'center', -fill => $col);
}