1 # canvas.tcl - Handy canvas-related commands.
2 # Copyright (C) 1997 Cygnus Solutions.
3 # Written by Tom Tromey <tromey@cygnus.com>.
5 # Set scroll region on canvas.
6 proc set_scroll_region {canvas} {
7 set bbox [$canvas bbox all]
8 if {[llength $bbox]} then {
9 set sr [lreplace $bbox 0 1 0 0]
14 # Don't include borders in the scrollregion.
15 set delta [expr {2 * ([$canvas cget -borderwidth]
16 + [$canvas cget -highlightthickness])}]
18 set ww [winfo width $canvas]
19 if {[lindex $sr 2] < $ww} then {
20 set sr [lreplace $sr 2 2 [expr {$ww - $delta}]]
23 set wh [winfo height $canvas]
24 if {[lindex $sr 3] < $wh} then {
25 set sr [lreplace $sr 3 3 [expr {$wh - $delta}]]
28 $canvas configure -scrollregion $sr