#!/usr/bin/perl 
use warnings;
use strict;
use Tk;
use Tk::JPEG;
use Tk::PNG;

#demonstrates need for subwidget method
#on Scrolled Canvas, to use lower or raise

my $mw = new MainWindow;

my $canvas  = $mw->Scrolled('Canvas', 
       -bg  => 'white',
       -xscrollincrement => 1,
       -yscrollincrement => 1,
       -confine => 1,
       -scrollbars => 'se',
       -width => 200,
       -height => 200,
       -closeenough =>3,
       -scrollregion => [ 0, 0, 500, 500 ], 
)->pack(qw/ -fill both -expand 1 -side top/);


my $realcanvas = $canvas->Subwidget('scrolled');

$mw->Button(-text=>"Raise Bunny",
            -command => sub{
     # $canvas->lower( 'bunny' ,'tux' ); # will cause error
     # need subwidget of the scrolled canvas

     $realcanvas->raise( 'bunny' ,'tux' );
        })->pack();

$mw->Button(-text=>"Lower Bunny",
            -command => sub{
         $realcanvas->lower( 'bunny' ,'tux' );
        })->pack();





my $tux = $mw->Photo(-data => get_tux() );
$canvas->createImage( 0, 0, -image => $tux, 
                            -anchor => 'nw',
                -tags => ['tux'],
                 );

my $bunny = $mw->Photo(-data => get_bunny() );
$canvas->createImage( 40, 40, -image => $bunny, 
                            -anchor => 'nw',
                -tags => ['bunny'],
                 );


my $lineseg = $canvas->createLine(
         1,1,200,200, 
         -fill => 'red',
         -tags => ['line']
     );

# $canvas->lower( 'bunny' ,'tux' ); # will cause error
# need subwidget
my $realcanvas = $canvas->Subwidget('scrolled');
$realcanvas->lower( 'bunny' ,'tux' );

MainLoop;


sub get_bunny{

return  
'iVBORw0KGgoAAAANSUhEUgAAAB4AAAAjEAIAAABcJvHFAAAACXBIWXMAAAsSAAALEgHS3
+X78AAAD
F0lEQVR42u1YL+yqUBj1vfcLbhY3C44is8BIREYSG9FoNBqNkok2aFhp2BhJDWyadCZN/i
+lOGxan
jRdOuRsPxl/f+23vJKfX7x6+73znu5dK5RviV9QPDMMwDIPP7/f7/X6XTWU0Go1Go06n0+
+l0PM/z
PC91CNu2bduWZVmW5bLpjsfj8XgcBEEQBJPJZDKZZAw0n8/n8zkCGYZhGIYgCIIgFEt3OB
+wOh8OA
gKZpmqZlDDedTqfTKRnO933f95GVer1er9fz0BVFURRFxCR3QfyMQfv9fr/fDyLgOI7jON
+mo419k
JUkMBoPBYJCRNBrxdrvdbrco6qvVarVaIWdFpQO/5tIcFBbE4nQ6nU6nJIpHjlGlEklTFE
+VRFDIa
T32/3+/3+3jqHMdxHBcfB2sK6HFFURRFeb1er9crfksoNUrr0GvUfxGfnA+FmX+QALDItG
+LDA6O2
pQyCJFkPqxMDK2p9LodOAhQaLRjfoKRGo2wObl3G8PoDsA0Gb5Q5oonjfSNKTh96AOh+u9
+1ut1uS
FuZrONPJ7bJ06tA9TDDsD6QkCnDltEDRkV1Q9AnENyuk8hcyChkkcZKo5uv1er1er3S6cA
+PkFXSx
MQodPrXFg2zTEsVANhO2JNdEmVo80ub7K/lSDHPyLkNaXrVarVar2W46LMuyLFsKaZ7neZ
+4nvwFR
NGKeGjYajUajkXz9z+RLn8/n8/ms/ANIQXq5XC6Xy/v9fr/fvw3p9Xq9Xq9VVVVV9fF4PB
+6Pokhc
r9fr9Vr6s6Lf4dNpbS6/exQA3BHDt/fkPl3wwT85wlcEcrCHZyHO1tmOSl95iGLcQN80Td
+M0jTa1
LMuyLF3XdV03TdM0zWaz2Ww2Xdd1XRenDlDHgTbtvj/ykMZpDm/6LpfL5XLBmGi32+12G6
+Th5RAA
Pne73W63iwfGYFosFovF4kOZrtVqtVoN16TD4XA4HPAAKDp5yZUkSZIk1GGz2Ww2m91ut9
+vt0Mof
lcfxeDwej7PZbDaboRFbrVar1SJfIsLdYZfn8/l8Pue3y1zyiH9VAMFElb5Yp/+PcvAbH/
+25ox5S
PYYAAAAASUVORK5CYII=';
}


sub get_tux{

'/9j/4AAQSkZJRgABAQIASABIAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UH
+RofHh0a
HBwgJC4nICIsIxwcKDcpLDAxNDQ0Hyc5PTgyPC4zNDL/2wBDAQkJCQwLDBgNDRgyIRwhMj
+IyMjIy
MjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjL/wAARCAA8AE
+MDASIA
AhEBAxEB/8QAHAAAAgIDAQEAAAAAAAAAAAAAAAQFBwIDCAYB/8QAMBAAAQMCBQMCBQMFAA
+AAAAAA
AQIDBAARBQYSITEHUXETYSIyQUKBFTOhI1KRscH/xAAaAQEBAQADAQAAAAAAAAAAAAAAAQ
+IDBQYE
/8QAIxEAAgEDAwQDAAAAAAAAAAAAAAECAwQREyExBRJBkVFSof/aAAwDAQACEQMRAD8Ap5
+brjgSF
uLUEgBIUomwACRb8ADwB2rCl5bymWgU8k2v2oiyPWGk/OP5oBiiilYkbEsanCJhsZ+S8r5
+Wo6CtR
97DegGqKZw3LWZpk6RDYwiY69GIS+0WiFNk8A34J+gPNaHW3GHVtPIU242opWhYsUkcgg8
+GgNa3E
Nga1AXr6CFC4NxUXKe9Z24+UbCm4CiWSD9DtQE07jmKvurdXiMrUo3Ol0pA8AbAew2FFR9
+FY0ofV
F7n8is9N2QexqPQstrCk8ipd1HqNKR3FQ6klKikixFbIS3qhcYuJ/tJ8V7LpFjWV8Pm4rh
+2aU6Yu
JMJZD11AJsoK0lSTqAJA3Haq9Ze0sutk7Ebb/WiEtpucwt9OppKwVp7i+9R8A6jVO/Ucfm
+TGMBZm
YEsxnI6npBaccdZvpeSLG4sQAFEXCQeDVV9a1uzsyJxVjBZUGO6wht5x1KbLdBVc3SSPl0
+jm/wAN
WejGn3mmpGH4Yqdh7qApp2K+gK8FKym1uOT+K8x1CzNHiZUmQMSYaRMmJ0sRQ6HFJTt8a7
+CwII2t
fgb828pa9avalyoSgmm+E91++POV6OzqWlGNPKb29FA1KQkaI4J+43qOab9V1KO53qZAsA
+BwK9Yd
YFFZBtZFwhVvFFTKGDGkpse49VPP3Cnaxct6ar8WNUELW+HEkT5bUSK0t191QQ22gXKiTY
+ACtFWR
0LQ0vqnh/qtayG3Sg2uEq9NW/wDugLEyX0XzHBw0KxDM8jDC4NRiRPj0+VXtfwD5rxHVLp
+PiOUo/
64nE14nDccCHXHEkONqPGrc3B7966qqMzBgcPMuAy8HnhRjSkaVaDYixBBHuCAfxWFTgpO
+SW7K5N
rBxFAaGlTvJ48U7Tmasrzsi5qfwmbct31NPWsHWz8qh/33BFJ1shaLs7qHiTpmwoOMRoz/
+8AUbai
IfDQB3ukEnY882322tRUE9nTMDjzjjeKS46VqKvSYkOIQm+5skKsB7DaigPF0vMVpjH32p
+ik8Q/b
R5oCPrq3ofktnL+UGsYebviOJoDhUoboa+1I87KPe47VyvHSFyWkngrAP+a71jR24kVmMy
+nS0yhL
aE9kgWAoDbRRRQFc9ZsnR8zZJkzUpAn4W2qSy59SgC60n2IF/IHvXLkVZcjpJ5GxrrzqfN
+dgdM8f
fZ06zFLXxC+yyEH+FGuQIP7Fve9AW9Iw+JIfU7h+TJaoqrFsuy1sqO290FSrb3+p7+1FQK
+HXEoAW
UuqAtrW2gqPnaivld3BPGGcmkz//2Q==';

}
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