# items.tcl -- # # This demonstration script creates a canvas that displays the # canvas item types. if {![info exists widgetDemo]} { error "This script should be run from the \"widget\" demo." } package require Tk set w .items catch {destroy $w} toplevel $w wm title $w "Canvas Item Demonstration" wm iconname $w "Items" positionWindow $w set 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 Left-Button drag:\tmoves item under pointer.\n Middle-Button drag:\trepositions view.\n Right-Button drag:\tstrokes out area.\n Ctrl+f:\t\tprints items under area." pack $w.msg -side top ## See Code / Dismiss buttons set btns [addSeeDismiss $w.buttons $w] pack $btns -side bottom -fill x frame $w.frame pack $w.frame -side top -fill both -expand yes 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" ttk::scrollbar $w.frame.vscroll -command "$c yview" ttk::scrollbar $w.frame.hscroll -orient horiz -command "$c xview" grid $c -in $w.frame \ -row 0 -column 0 -rowspan 1 -columnspan 1 -sticky news grid $w.frame.vscroll \ -row 0 -column 1 -rowspan 1 -columnspan 1 -sticky news grid $w.frame.hscroll \ -row 1 -column 0 -rowspan 1 -columnspan 1 -sticky news grid rowconfig $w.frame 0 -weight 1 -minsize 0 grid columnconfig $w.frame 0 -weight 1 -minsize 0 # Display a 3x3 rectangular grid. $c create rect 0c 0c 30c 24c -width 2 $c create line 0c 8c 30c 8c -width 2 $c create line 0c 16c 30c 16c -width 2 $c create line 10c 0c 10c 24c -width 2 $c create line 20c 0c 20c 24c -width 2 set font1 {Helvetica 12} set font2 {Helvetica 24 bold} if {[winfo depth $c] > 1} { set blue DeepSkyBlue3 set red red set bisque bisque3 set green SeaGreen3 } else { set blue black set red black set bisque black set green black } # Set up demos within each of the areas of the grid. $c create text 5c .2c -text Lines -anchor n $c create line 1c 1c 3c 1c 1c 4c 3c 4c -width 2m -fill $blue \ -cap butt -join miter -tags item $c create line 4.67c 1c 4.67c 4c -arrow last -tags item $c create line 6.33c 1c 6.33c 4c -arrow both -tags item $c create 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 -tags item # Main widget program sets variable tk_demoDirectory $c create line 1c 5c 7c 5c 7c 7c 9c 7c -width .5c \ -stipple @[file join $tk_demoDirectory images gray25.xbm] \ -arrow both -arrowshape {15 15 7} -tags item $c create line 1c 7c 1.75c 5.8c 2.5c 7c 3.25c 5.8c 4c 7c -width .5c \ -cap round -join round -tags item $c create text 15c .2c -text "Curves (smoothed lines)" -anchor n $c create line 11c 4c 11.5c 1c 13.5c 1c 14c 4c -smooth on \ -fill $blue -tags item $c create line 15.5c 1c 19.5c 1.5c 15.5c 4.5c 19.5c 4c -smooth on \ -arrow both -width 3 -tags item $c create 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 @[file join $tk_demoDirectory images gray25.xbm] \ -fill $red -tags item $c create text 25c .2c -text Polygons -anchor n $c create 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 \ -outline {} -width 4 -tags item $c create polygon 25c 4c 25c 4c 25c 1c 26c 1c 27c 4c 28c 1c \ 29c 1c 29c 4c 29c 4c -fill $red -outline {} -smooth on -tags item $c create 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 @[file join $tk_demoDirectory images gray25.xbm] \ -fill $blue -outline {} -tags item $c create text 5c 8.2c -text Rectangles -anchor n $c create rectangle 1c 9.5c 4c 12.5c -outline $red -width 3m -tags item $c create rectangle 0.5c 13.5c 4.5c 15.5c -fill $green -tags item $c create rectangle 6c 10c 9c 15c -outline {} \ -stipple @[file join $tk_demoDirectory images gray25.xbm] \ -fill $blue -tags item $c create text 15c 8.2c -text Ovals -anchor n $c create oval 11c 9.5c 14c 12.5c -outline $red -width 3m -tags item $c create oval 10.5c 13.5c 14.5c 15.5c -fill $green -tags item $c create oval 16c 10c 19c 15c -outline {} \ -stipple @[file join $tk_demoDirectory images gray25.xbm] \ -fill $blue -tags item $c create text 25c 8.2c -text Text -anchor n $c create rectangle 22.4c 8.9c 22.6c 9.1c $c create 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 $c create rectangle 25.4c 10.9c 25.6c 11.1c $c create text 25.5c 11c -anchor w -font $font1 -fill $blue \ -text "Several lines,\n each centered\nindividually,\nand all anchored\nat the left edge." \ -justify center -tags item $c create rectangle 24.9c 13.9c 25.1c 14.1c catch { $c create text 25c 14c -font $font2 -anchor c -fill $red -angle 15 \ -text "Angled characters" -tags item } $c create text 5c 16.2c -text Arcs -anchor n $c create arc 0.5c 17c 7c 20c -fill $green -outline black \ -start 45 -extent 270 -style pieslice -tags item $c create arc 6.5c 17c 9.5c 20c -width 4m -style arc \ -outline $blue -start -135 -extent 270 -tags item \ -outlinestipple @[file join $tk_demoDirectory images gray25.xbm] $c create arc 0.5c 20c 9.5c 24c -width 4m -style pieslice \ -fill {} -outline $red -start 225 -extent -90 -tags item $c create arc 5.5c 20.5c 9.5c 23.5c -width 4m -style chord \ -fill $blue -outline {} -start 45 -extent 270 -tags item $c create text 15c 16.2c -text "Bitmaps and Images" -anchor n catch { image create photo items.ousterhout \ -file [file join $tk_demoDirectory images ouster.png] image create photo items.ousterhout.active -format "png -alpha 0.5" \ -file [file join $tk_demoDirectory images ouster.png] $c create image 13c 20c -tags item -image items.ousterhout \ -activeimage items.ousterhout.active } $c create bitmap 17c 18.5c -tags item \ -bitmap @[file join $tk_demoDirectory images noletter.xbm] $c create bitmap 17c 21.5c -tags item \ -bitmap @[file join $tk_demoDirectory images letters.xbm] $c create text 25c 16.2c -text Windows -anchor n button $c.button -text "Press Me" -command "butPress $c $red" $c create window 21c 18c -window $c.button -anchor nw -tags item entry $c.entry -width 20 -relief sunken $c.entry insert end "Edit this text" $c create window 21c 21c -window $c.entry -anchor nw -tags item scale $c.scale -from 0 -to 100 -length 6c -sliderlength .4c \ -width .5c -tickinterval 0 $c create window 28.5c 17.5c -window $c.scale -anchor n -tags item $c create text 21c 17.9c -text Button: -anchor sw $c create text 21c 20.9c -text Entry: -anchor sw $c create text 28.5c 17.4c -text Scale: -anchor s # Set up event bindings for canvas: $c bind item "itemEnter $c" $c bind item "itemLeave $c" if {[tk windowingsystem] eq "aqua" && ![package vsatisfies [package provide Tk] 8.7-]} { bind $c "itemMark $c %x %y" bind $c "itemStroke $c %x %y" bind $c "$c scan mark %x %y" bind $c "$c scan dragto %x %y" } else { bind $c "$c scan mark %x %y" bind $c "$c scan dragto %x %y" bind $c "itemMark $c %x %y" bind $c "itemStroke $c %x %y" } bind $c <> "itemsUnderArea $c" bind $c "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" || $type == "image"} { set restoreCmd {} return } elseif {$type == "bitmap"} { set bg [lindex [$c itemconf current -background] 4] set restoreCmd [list $c itemconfig current -background $bg] $c itemconfig current -background SteelBlue2 return } elseif {$type == "image"} { set restoreCmd [list $c itemconfig current -state normal] $c itemconfig current -state active return } set fill [lindex [$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] >= 0} { 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] >= 0} { 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 "Oooohhh!!" -fill $color -anchor n] after 500 "$w delete $i" }