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1 files changed, 173 insertions, 0 deletions

diff --git a/library/demos/ruler.tcl b/library/demos/ruler.tcl
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+# ruler.tcl --
+#
+# This demonstration script creates a canvas widget that displays a ruler
+# with tab stops that can be set, moved, and deleted.
+#
+# SCCS: @(#) ruler.tcl 1.9 97/03/02 16:17:33
+
+if {![info exists widgetDemo]} {
+    error "This script should be run from the \"widget\" demo."
+}
+
+# rulerMkTab --
+# This procedure creates a new triangular polygon in a canvas to
+# represent a tab stop.
+#
+# Arguments:
+# c -		The canvas window.
+# x, y -	Coordinates at which to create the tab stop.
+
+proc rulerMkTab {c x y} {
+    upvar #0 demo_rulerInfo v
+    $c create polygon $x $y [expr $x+$v(size)] [expr $y+$v(size)] \
+	    [expr $x-$v(size)] [expr $y+$v(size)]
+}
+
+set w .ruler
+global tk_library
+catch {destroy $w}
+toplevel $w
+wm title $w "Ruler Demonstration"
+wm iconname $w "ruler"
+positionWindow $w
+set c $w.c
+
+label $w.msg -font $font -wraplength 5i -justify left -text "This canvas widget shows a mock-up of a ruler.  You can create tab stops by dragging them out of the well to the right of the ruler.  You can also drag existing tab stops.  If you drag a tab stop far enough up or down so that it turns dim, it will be deleted when you release the mouse button."
+pack $w.msg -side top
+
+frame $w.buttons
+pack $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"
+pack $w.buttons.dismiss $w.buttons.code -side left -expand 1
+
+canvas $c -width 14.8c -height 2.5c
+pack $w.c -side top -fill x
+
+set demo_rulerInfo(grid) .25c
+set demo_rulerInfo(left) [winfo fpixels $c 1c]
+set demo_rulerInfo(right) [winfo fpixels $c 13c]
+set demo_rulerInfo(top) [winfo fpixels $c 1c]
+set demo_rulerInfo(bottom) [winfo fpixels $c 1.5c]
+set demo_rulerInfo(size) [winfo fpixels $c .2c]
+set demo_rulerInfo(normalStyle) "-fill black"
+if {[winfo depth $c] > 1} {
+    set demo_rulerInfo(activeStyle) "-fill red -stipple {}"
+    set demo_rulerInfo(deleteStyle) [list -fill red \
+	    -stipple @[file join $tk_library demos images gray25.bmp]]
+} else {
+    set demo_rulerInfo(activeStyle) "-fill black -stipple {}"
+    set demo_rulerInfo(deleteStyle) [list -fill black \
+	    -stipple @[file join $tk_library demos images gray25.bmp]]
+}
+
+$c create line 1c 0.5c 1c 1c 13c 1c 13c 0.5c -width 1
+for {set i 0} {$i < 12} {incr i} {
+    set x [expr $i+1]
+    $c create line ${x}c 1c ${x}c 0.6c -width 1
+    $c create line $x.25c 1c $x.25c 0.8c -width 1
+    $c create line $x.5c 1c $x.5c 0.7c -width 1
+    $c create line $x.75c 1c $x.75c 0.8c -width 1
+    $c create text $x.15c .75c -text $i -anchor sw
+}
+$c addtag well withtag [$c create rect 13.2c 1c 13.8c 0.5c \
+	-outline black -fill [lindex [$c config -bg] 4]]
+$c addtag well withtag [rulerMkTab $c [winfo pixels $c 13.5c] \
+	[winfo pixels $c .65c]]
+
+$c bind well <1> "rulerNewTab $c %x %y"
+$c bind tab <1> "rulerSelectTab $c %x %y"
+bind $c <B1-Motion> "rulerMoveTab $c %x %y"
+bind $c <Any-ButtonRelease-1> "rulerReleaseTab $c"
+
+# rulerNewTab --
+# Does all the work of creating a tab stop, including creating the
+# triangle object and adding tags to it to give it tab behavior.
+#
+# Arguments:
+# c -		The canvas window.
+# x, y -	The coordinates of the tab stop.
+
+proc rulerNewTab {c x y} {
+    upvar #0 demo_rulerInfo v
+    $c addtag active withtag [rulerMkTab $c $x $y]
+    $c addtag tab withtag active
+    set v(x) $x
+    set v(y) $y
+    rulerMoveTab $c $x $y
+}
+
+# rulerSelectTab --
+# This procedure is invoked when mouse button 1 is pressed over
+# a tab.  It remembers information about the tab so that it can
+# be dragged interactively.
+#
+# Arguments:
+# c -		The canvas widget.
+# x, y -	The coordinates of the mouse (identifies the point by
+#		which the tab was picked up for dragging).
+
+proc rulerSelectTab {c x y} {
+    upvar #0 demo_rulerInfo v
+    set v(x) [$c canvasx $x $v(grid)]
+    set v(y) [expr $v(top)+2]
+    $c addtag active withtag current
+    eval "$c itemconf active $v(activeStyle)"
+    $c raise active
+}
+
+# rulerMoveTab --
+# This procedure is invoked during mouse motion events to drag a tab.
+# It adjusts the position of the tab, and changes its appearance if
+# it is about to be dragged out of the ruler.
+#
+# Arguments:
+# c -		The canvas widget.
+# x, y -	The coordinates of the mouse.
+
+proc rulerMoveTab {c x y} {
+    upvar #0 demo_rulerInfo v
+    if {[$c find withtag active] == ""} {
+	return
+    }
+    set cx [$c canvasx $x $v(grid)]
+    set cy [$c canvasy $y]
+    if {$cx < $v(left)} {
+	set cx $v(left)
+    }
+    if {$cx > $v(right)} {
+	set cx $v(right)
+    }
+    if {($cy >= $v(top)) && ($cy <= $v(bottom))} {
+	set cy [expr $v(top)+2]
+	eval "$c itemconf active $v(activeStyle)"
+    } else {
+	set cy [expr $cy-$v(size)-2]
+	eval "$c itemconf active $v(deleteStyle)"
+    }
+    $c move active [expr $cx-$v(x)] [expr $cy-$v(y)]
+    set v(x) $cx
+    set v(y) $cy
+}
+
+# rulerReleaseTab --
+# This procedure is invoked during button release events that end
+# a tab drag operation.  It deselects the tab and deletes the tab if
+# it was dragged out of the ruler.
+#
+# Arguments:
+# c -		The canvas widget.
+# x, y -	The coordinates of the mouse.
+
+proc rulerReleaseTab c {
+    upvar #0 demo_rulerInfo v
+    if {[$c find withtag active] == {}} {
+	return
+    }
+    if {$v(y) != [expr $v(top)+2]} {
+	$c delete active
+    } else {
+	eval "$c itemconf active $v(normalStyle)"
+	$c dtag active
+    }
+}