Updated example to show a canvas window hide technique

The "widgets" on a canvas, are not widgets, they are "items" on a canvas. To make them disappear/reappear you have 2 choices. 1. is to move them way off the screen to some location out of view, like to -2000,-2000.

2. You can use the tag lower/raise mechanism to hide them under a background. Canvas window items are special....you may need to move them, as they don't respond to raise/lower.

#!/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' ,'background' ); })->pack(); $mw->Button(-text=>"Lower Bunny", -command => sub{ $realcanvas->lower( 'bunny' ,'background' ); })->pack(); my $rect = $canvas->createRectangle(0,0,500, 500, -fill => 'orange', -tags => ['background'], ); my $bunny = $mw->Photo(-data => get_bunny() ); $canvas->createImage( 40, 40, -image => $bunny, -anchor => 'nw', -tags => ['bunny'], ); my $window = $canvas->Checkbutton(-text=> 'Foo'); my $win = $canvas->createWindow(20,20, -window=> $window, ); $canvas->move($win,-1000,-1000); #dx, dy $mw->Button(-text=>"Show Checkbox", -command => sub{ $canvas->move($win, 1000,1000 ); })->pack(); $mw->Button(-text=>"Hide Checkbox", -command => sub{ $canvas->move($win, -1000,-1000 ); })->pack(); # $canvas->lower( 'bunny' ,'background' ); # will cause error # need subwidget $realcanvas->lower( 'bunny' ,'background' ); 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='; }

I'm not really a human, but I play one on earth CandyGram for Mongo

In reply to Re: Fogetting Tk Canvas widgets by zentara
in thread Fogetting Tk Canvas widgets by merrymonk

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