# items.tcl -- # # This demonstration script creates a canvas that displays the # canvas item types. # # RCS: @(#) $Id: items.tcl,v 1.3 2001/06/14 10:56:58 dkf Exp $ our $widgetDemo; unless ($widgetDemo) { die "This script should be run from the \"widget\" demo." } my $w = '.items'; $interp->call('destroy', $w); toplevel $w; wm('title', $w, "Canvas Item Demonstration"); wm('iconname', $w, "Items"); positionWindow($w); my $c = "$w.frame.c"; label "$w.msg", -font=>$font, -wraplength=>'5i', -justify=>'left', -text=>"This window contains a canvas widget with examples of the various kinds of items supported by canvases. The following operations are supported:\n Button-1 drag:\tmoves item under pointer.\n Button-2 drag:\trepositions view.\n Button-3 drag:\tstrokes out area.\n Ctrl+f:\t\tprints items under area."; tkpack "$w.msg", -side=>'top'; frame "$w.buttons"; tkpack "$w.buttons", -side=>'bottom', -fill=>'x', -pady=>'2m'; button "$w.buttons.dismiss", -text=>'Dismiss', -command=>"destroy $w"; button "$w.buttons.code", -text=>"See Code", -command=>"showCode $w"; tkpack "$w.buttons.dismiss", "$w.buttons.code", -side=>'left', -expand=>1; frame "$w.frame"; tkpack "$w.frame", -side=>'top', -fill=>'both', -expand=>'yes'; my $canv = canvas $c, -scrollregion=>'0c 0c 30c 24c', -width=>'15c', -height=>'10c', -relief=>'sunken', -borderwidth=>2, -xscrollcommand=>"$w.frame.hscroll set", -yscrollcommand=>"$w.frame.vscroll set"; scrollbar "$w.frame.vscroll", -command=> "$c yview"; scrollbar "$w.frame.hscroll", -orient=>'horiz', -command=>"$c xview"; grid ($c, -in=>"$w.frame", qw/-row 0 -column 0 -rowspan 1 -columnspan 1 -sticky news/); grid ("$w.frame.vscroll", qw/-row 0 -column 1 -rowspan 1 -columnspan 1 -sticky news/); grid ("$w.frame.hscroll", qw/-row 1 -column 0 -rowspan 1 -columnspan 1 -sticky news/); grid ( "rowconfig", "$w.frame"=>0, qw/-weight 1 -minsize 0/); grid ("columnconfig", "$w.frame"=>0, qw/-weight 1 -minsize 0/); # Display a 3x3 rectangular grid. $canv-> create (qw/rect 0c 0c 30c 24c -width 2/); $canv-> create (qw/line 0c 8c 30c 8c -width 2/); $canv-> create (qw/line 0c 16c 30c 16c -width 2/); $canv-> create (qw/line 10c 0c 10c 24c -width 2/); $canv-> create (qw/line 20c 0c 20c 24c -width 2/); my $font1 = 'Helvetica 12'; my $font2 = 'Helvetica 24 bold'; if ($interp->Eval("winfo depth $c") > 1) { $blue = 'DeepSkyBlue3'; $red = 'red'; $bisque = 'bisque3'; $green = 'SeaGreen3'; } else { $blue = 'black'; $red = 'black'; $bisque = 'black'; $green = 'black'; } # Set up demos within each of the areas of the grid. $canv-> create (qw/text 5c .2c -text Lines -anchor n/); $canv-> create (qw/line 1c 1c 3c 1c 1c 4c 3c 4c -width 2m -fill/, $blue, qw/ -cap butt -join miter -tags item/); $canv-> create (qw/line 4.67c 1c 4.67c 4c -arrow last -tags item/); $canv-> create (qw/line 6.33c 1c 6.33c 4c -arrow both -tags item/); $canv-> create (qw/line 5c 6c 9c 6c 9c 1c 8c 1c 8c 4.8c 8.8c 4.8c 8.8c 1.2c 8.2c 1.2c 8.2c 4.6c 8.6c 4.6c 8.6c 1.4c 8.4c 1.4c 8.4c 4.4c -width 3 -fill/, $red, qw/-tags item/); $canv-> create (qw/line 1c 5c 7c 5c 7c 7c 9c 7c -width .5c -stipple/, "\@./images/gray25.bmp", -arrow=>'both', -arrowshape=>'15 15 7', -tags=>'item'); $canv-> create qw/line 1c 7c 1.75c 5.8c 2.5c 7c 3.25c 5.8c 4c 7c -width .5c -cap round -join round -tags item/; $canv-> create(qw/text 15c .2c -text/, "Curves (smoothed lines)", -anchor=>'n'); $canv-> create(qw/line 11c 4c 11.5c 1c 13.5c 1c 14c 4c -smooth on -fill/, $blue, -tags=>'item'); $canv-> create qw/line 15.5c 1c 19.5c 1.5c 15.5c 4.5c 19.5c 4c -smooth on -arrow both -width 3 -tags item/; $canv-> create (qw|line 12c 6c 13.5c 4.5c 16.5c 7.5c 18c 6c 16.5c 4.5c 13.5c 7.5c 12c 6c -smooth on -width 3m -cap round -stipple @./images/gray25.bmp -fill|, $red, -tags=>'item'); $canv-> create qw/text 25c .2c -text Polygons -anchor n/; $canv-> create(qw/polygon 21c 1.0c 22.5c 1.75c 24c 1.0c 23.25c 2.5c 24c 4.0c 22.5c 3.25c 21c 4.0c 21.75c 2.5c -fill/, $green, qw/-outline black -width 4 -tags item/); $canv-> create(qw/polygon 25c 4c 25c 4c 25c 1c 26c 1c 27c 4c 28c 1c 29c 1c 29c 4c 29c 4c -fill/, $red, qw/-smooth on -tags item/); $canv-> create qw|polygon 22c 4.5c 25c 4.5c 25c 6.75c 28c 6.75c 28c 5.25c 24c 5.25c 24c 6.0c 26c 6c 26c 7.5c 22c 7.5c -stipple @./images/gray25.bmp -outline black -tags item|; $canv-> create qw/text 5c 8.2c -text Rectangles -anchor n/; $canv-> create(qw/rectangle 1c 9.5c 4c 12.5c -outline/, $red, qw/-width 3m -tags item/); $canv-> create(qw/rectangle 0.5c 13.5c 4.5c 15.5c -fill/, $green, -tags=>'item'); $canv-> create(rectangle=>'6c 10c 9c 15c', -outline=>'', -stipple=>'@./images/gray25.bmp', -fill=>$blue, -tags=>'item'); $canv-> create qw/text 15c 8.2c -text Ovals -anchor n/; $canv-> create(qw/oval 11c 9.5c 14c 12.5c -outline/, $red, qw/-width 3m -tags item/); $canv-> create(qw/oval 10.5c 13.5c 14.5c 15.5c -fill/, $green, -tags=>'item'); $canv-> create(oval=>'16c 10c 19c 15c', -outline=>'', -stipple=>'@./images/gray25.bmp', -fill=>$blue, -tags=>'item'); $canv-> create qw/text 25c 8.2c -text Text -anchor n/; $canv-> create qw/rectangle 22.4c 8.9c 22.6c 9.1c/; $canv-> create(qw/text 22.5c 9c -anchor n -font $font1 -width 4c/, -text=>"A short string of text, word-wrapped, justified left, and anchored north (at the top). The rectangles show the anchor points for each piece of text.", -tags=>'item'); $canv-> create qw/rectangle 25.4c 10.9c 25.6c 11.1c/; $canv-> create(qw/text 25.5c 11c -anchor w -font $font1 -fill/, $blue, -text=>"Several lines,\n each centered\nindividually,\nand all anchored\nat the left edge.", qw/-justify center -tags item/); $canv-> create qw/rectangle 24.9c 13.9c 25.1c 14.1c/; $canv-> create('text','25c', '14c', -font=>$font2, -anchor=>'c', -fill=>$red, -stipple=>'gray50', -text=>"Stippled characters", -tags=>'item'); $canv-> create qw/text 5c 16.2c -text Arcs -anchor n/; $canv-> create(qw/arc 0.5c 17c 7c 20c -fill/, $green, qw/-outline black -start 45 -extent 270 -style pieslice -tags item/); $canv-> create(qw|arc 6.5c 17c 9.5c 20c -width 4m -style arc -outline|, $blue, qw|-start -135 -extent 270 -tags item -outlinestipple @./images/gray25.bmp|); $canv-> create(qw/arc 0.5c 20c 9.5c 24c -width 4m -style pieslice -fill/, '', -outline=>$red, qw/-start 225 -extent -90 -tags item/); $canv-> create(qw/arc 5.5c 20.5c 9.5c 23.5c -width 4m -style chord -fill/, $blue, -outline=>'', qw/-start 45 -extent 270 -tags item/); $canv-> create qw/text 15c 16.2c -text Bitmaps -anchor n/; $canv-> create qw|bitmap 13c 20c -tags item -bitmap @./images/face.bmp|; $canv-> create qw|bitmap 17c 18.5c -tags item -bitmap @./images/noletter.bmp|; $canv-> create qw|bitmap 17c 21.5c -tags item -bitmap @./images/letters.bmp|; $canv-> create qw/text 25c 16.2c -text Windows -anchor n/; button "$c.button", -text=>"Press Me", -command=>"butPress $c $red"; $canv-> create('window', '21c', '18c', -window=>"$c.button", qw/-anchor nw -tags item/); my $entr = entry "$c.entry", -width=>20, -relief=>'sunken'; $entr->insert ('end', "Edit this text"); $canv-> create ('window', '21c', '21c', -window=>"$c.entry", -anchor=>'nw', -tags=>'item'); my $scale = scale "$c.scale", qw/-from 0 -to 100 -length 6c -sliderlength .4c -width .5c -tickinterval 0/; $canv-> create('window', '28.5c', '17.5c', -window=>"$c.scale", -anchor=>'n', -tags=>'item'); $canv-> create qw/text 21c 17.9c -text Button: -anchor sw/; $canv-> create qw/text 21c 20.9c -text Entry: -anchor sw/; $canv-> create qw/text 28.5c 17.4c -text Scale: -anchor s/; # # Following line defines all other subroutines in Tcl. # This was done only to prove the concept and not mandatory: all those code # should be written in Perl. Samples how to do that could be seen in other demo code. # The only difficulty could be vith events, see samples in "Text/Hypertext tag bindings" # demo. # $interp->Eval(<<'EOS'); set w .items set c "$w.frame.c" # Set up event bindings for canvas: $c bind item "itemEnter $c" $c bind item "itemLeave $c" bind $c <2> "$c scan mark %x %y" bind $c "$c scan dragto %x %y" bind $c <3> "itemMark $c %x %y" bind $c "itemStroke $c %x %y" bind $c "itemsUnderArea $c" bind $c <1> "itemStartDrag $c %x %y" bind $c "itemDrag $c %x %y" # Utility procedures for highlighting the item under the pointer: proc itemEnter {c} { global restoreCmd if {[winfo depth $c] == 1} { set restoreCmd {} return } set type [$c type current] if {$type == "window"} { set restoreCmd {} return } if {$type == "bitmap"} { set bg [lindex [$c itemconf current -background] 4] set restoreCmd [list $c itemconfig current -background $bg] $c itemconfig current -background SteelBlue2 return } set fill [lindex [$c itemconfig current -fill] 4] if {(($type == "rectangle") || ($type == "oval") || ($type == "arc")) && ($fill == "")} { set outline [lindex [$c itemconfig current -outline] 4] set restoreCmd "$c itemconfig current -outline $outline" $c itemconfig current -outline SteelBlue2 } else { set restoreCmd "$c itemconfig current -fill $fill" $c itemconfig current -fill SteelBlue2 } } proc itemLeave {c} { global restoreCmd eval $restoreCmd } # Utility procedures for stroking out a rectangle and printing what's # underneath the rectangle's area. proc itemMark {c x y} { global areaX1 areaY1 set areaX1 [$c canvasx $x] set areaY1 [$c canvasy $y] $c delete area } proc itemStroke {c x y} { global areaX1 areaY1 areaX2 areaY2 set x [$c canvasx $x] set y [$c canvasy $y] if {($areaX1 != $x) && ($areaY1 != $y)} { $c delete area $c addtag area withtag [$c create rect $areaX1 $areaY1 $x $y \ -outline black] set areaX2 $x set areaY2 $y } } proc itemsUnderArea {c} { global areaX1 areaY1 areaX2 areaY2 set area [$c find withtag area] set items "" foreach i [$c find enclosed $areaX1 $areaY1 $areaX2 $areaY2] { if {[lsearch [$c gettags $i] item] != -1} { lappend items $i } } puts stdout "Items enclosed by area: $items" set items "" foreach i [$c find overlapping $areaX1 $areaY1 $areaX2 $areaY2] { if {[lsearch [$c gettags $i] item] != -1} { lappend items $i } } puts stdout "Items overlapping area: $items" } set areaX1 0 set areaY1 0 set areaX2 0 set areaY2 0 # Utility procedures to support dragging of items. proc itemStartDrag {c x y} { global lastX lastY set lastX [$c canvasx $x] set lastY [$c canvasy $y] } proc itemDrag {c x y} { global lastX lastY set x [$c canvasx $x] set y [$c canvasy $y] $c move current [expr {$x-$lastX}] [expr {$y-$lastY}] set lastX $x set lastY $y } # Procedure that's invoked when the button embedded in the canvas # is invoked. proc butPress {w color} { set i [$w create text 25c 18.1c -text "Ouch!!" -fill $color -anchor n] after 500 "$w delete $i" } EOS