# This demonstration script creates a canvas widget with a text
# item that can be edited and reconfigured in various ways.
# RCS: @(#) $Id: ctext.tcl,v 1.3 2001/06/14 10:56:58 dkf Exp $
if {![info exists widgetDemo
]} {
error "This script should be run from the \"widget\" demo."
wm title
$w "Canvas Text Demonstration"
label $w.msg
-font $font -wraplength 5i
-justify left
-text "This window displays a string of text to demonstrate the text facilities of canvas widgets. You can click in the boxes to adjust the position of the text relative to its positioning point or change its justification. The text also supports the following simple bindings for editing:
1. You can point, click, and type.
2. You can also select with button 1.
3. You can copy the selection to the mouse position with button 2.
4. Backspace and Control+h delete the selection if there is one;
otherwise they delete the character just before the insertion cursor.
5. Delete deletes the selection if there is one; otherwise it deletes
the character just after the insertion cursor."
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 -relief flat
-borderwidth 0 -width 500 -height 350
pack $w.c
-side top
-expand yes
-fill both
set textFont
{Helvetica
24}
$c create rectangle
245 195 255 205 -outline black
-fill red
# First, create the text item and give it bindings so it can be edited.
$c addtag
text withtag
[$c create
text 250 200 -text "This is just a string of text to demonstrate the text facilities of canvas widgets. Bindings have been been defined to support editing (see above)." -width 440 -anchor n
-font {Helvetica
24} -justify left
]
$c bind text <1> "textB1Press $c %x %y"
$c bind text <B1-Motion
> "textB1Move $c %x %y"
$c bind text <Shift-1
> "$c select adjust current @%x,%y"
$c bind text <Shift-B1-Motion
> "textB1Move $c %x %y"
$c bind text <KeyPress
> "textInsert $c %A"
$c bind text <Return
> "textInsert $c \\n"
$c bind text <Control-h
> "textBs $c"
$c bind text <BackSpace
> "textBs $c"
$c bind text <Delete
> "textDel $c"
$c bind text <2> "textPaste $c @%x,%y"
# Next, create some items that allow the text's anchor position
proc mkTextConfig
{w x y
option value color
} {
set item
[$w create rect
$x $y [expr {$x+30}] [expr {$y+30}] \
-outline black
-fill $color -width 1]
$w bind $item <1> "$w itemconf text $option $value"
$w addtag config withtag
$item
mkTextConfig
$c $x $y -anchor se
$color
mkTextConfig
$c [expr {$x+30}] [expr {$y }] -anchor s
$color
mkTextConfig
$c [expr {$x+60}] [expr {$y }] -anchor sw
$color
mkTextConfig
$c [expr {$x }] [expr {$y+30}] -anchor e
$color
mkTextConfig
$c [expr {$x+30}] [expr {$y+30}] -anchor center
$color
mkTextConfig
$c [expr {$x+60}] [expr {$y+30}] -anchor w
$color
mkTextConfig
$c [expr {$x }] [expr {$y+60}] -anchor ne
$color
mkTextConfig
$c [expr {$x+30}] [expr {$y+60}] -anchor n
$color
mkTextConfig
$c [expr {$x+60}] [expr {$y+60}] -anchor nw
$color
set item
[$c create rect
\
[expr {$x+40}] [expr {$y+40}] [expr {$x+50}] [expr {$y+50}] \
-outline black
-fill red
]
$c bind $item <1> "$c itemconf text -anchor center"
$c create
text [expr {$x+45}] [expr {$y-5}] \
-text {Text Position
} -anchor s
-font {Times
24} -fill brown
# Lastly, create some items that allow the text's justification to be
mkTextConfig
$c $x $y -justify left
$color
mkTextConfig
$c [expr {$x+30}] $y -justify center
$color
mkTextConfig
$c [expr {$x+60}] $y -justify right
$color
$c create
text [expr {$x+45}] [expr {$y-5}] \
-text {Justification
} -anchor s
-font {Times
24} -fill brown
$c bind config
<Enter
> "textEnter $c"
$c bind config
<Leave
> "$c itemconf current -fill \$textConfigFill"
set textConfigFill
[lindex [$w itemconfig current
-fill] 4]
$w itemconfig current
-fill black
proc textInsert
{w
string} {
catch {$w dchars
text sel.first sel.last
}
$w insert
text insert
$string
$w insert
text $pos [selection get
]
proc textB1Press
{w x y
} {
$w icursor current
@$x,$y
$w select from current
@$x,$y
proc textB1Move
{w x y
} {
$w select to current
@$x,$y
if {![catch {$w dchars
text sel.first sel.last
}]} {
set char
[expr {[$w index
text insert
] - 1}]
if {$char >= 0} {$w dchar
text $char}
if {![catch {$w dchars
text sel.first sel.last
}]} {