A little list selector
Summary
Richard Suchenwirth 2002-04-03: Here is another mini-megawidget: two listboxes (with scrollbar), where items from the left listbox ("choices") can be copied to the right listbox by double-clicking on them.
Description
Delete an item from the right listbox ("chosen") by double clicking. The content of the "chosen" list can be retrieved at any time in a linked global variable; also you can change the "choices" by assigning to another linked list variable. A vertical button bar offers "->" (take one), "<-" (remove one); ">>" (take all) and "<<" (remove all) actions. You can suppress the button bar by specifying -buttons 0.
Options aren't very many yet; you can select whether a choice can be added multiply or not with the -unique {0|1} switch, specify -listvar and -selvar, and determine the background color.
Reconfiguring isn't implemented either (yet) - feel free to add more bells and whistles!
MG 2004-04-29: The Iwidgets package also offers one of these, in the form of ::iwidgets::disjointlistbox::. The Iwidgets version is less attractive though (IMHO; I prefer the add/remove buttons where Richard put them), and also doesn't offer the (Add/Remove) All feature.
KPV: Also, tklib has swaplist.
MBS: Also see swaptablelist
proc listbox2 {w args} {
array set opt {
-listvar "" -selvar "" -bg white -unique 1 -buttons 1
}
array set opt $args
frame $w
listbox $w.0 -yscrollcommand [list $w.y0 set] -listvar $opt(-listvar)\
-bg $opt(-bg)
scrollbar $w.y0 -ori vert -command [list $w.0 yview]
if {$opt(-buttons)} {
buttons $w.b [list \
-> "ladd $opt(-selvar) \[selection get\]" \
<- "lremove $opt(-selvar) \[selection get\]" \
>> "set $opt(-selvar) \[set $opt(-listvar)\]" \
<< "set $opt(-selvar) {}"]
}
listbox $w.1 -yscrollcommand [list $w.y1 set] -listvar $opt(-selvar)\
-bg $opt(-bg)
scrollbar $w.y1 -ori vert -command [list $w.1 yview]
if {$opt(-unique)} {
bind $w.0 <Double-1> "ladd $opt(-selvar) \[selection get\]"
} else {
bind $w.0 <Double-1> "lappend $opt(-selvar) \[selection get\]"
}
bind $w.1 <Double-1> "lremove $opt(-selvar) \[selection get\]"
set children [winfo children $w]
eval grid $children -sticky news
grid rowconfigure $w 0 -weight 1
grid columnconfigure $w 0 -weight 1
grid columnconfigure $w [expr {[llength $children]-2}] -weight 1
set w
}
proc buttons {w buttonlist args} {
frame $w
foreach {label command} $buttonlist {
button $w.b$label -text $label -command $command
}
eval pack [winfo children $w] -side top -fill x -padx 0
set w
}
proc ladd {listName element} {
upvar 1 $listName list
if {[lsearch $list $element]<0} {lappend list $element}
set list
}
proc lremove {listName element} {
upvar 1 $listName list
set pos [lsearch $list $element]
set list [lreplace $list $pos $pos]
}
#----------------------------------------------demo and test:
if {[file tail [info script]] == [file tail $argv0]} {
set testlist {foo bar grill baz and some more words}
pack [label .0 -text "Make your selection:"]
pack [listbox2 .x -listvar testlist -selvar selected] -expand 1 -fill both
bind . <Return> {puts $selected}
}