figenc

listbox.tcl (14595B)

---

 # listbox.tcl --
 #
 # This file defines the default bindings for Tk listbox widgets
 # and provides procedures that help in implementing those bindings.
 #
 # Copyright (c) 1994 The Regents of the University of California.
 # Copyright (c) 1994-1995 Sun Microsystems, Inc.
 # Copyright (c) 1998 by Scriptics Corporation.
 #
 # See the file "license.terms" for information on usage and redistribution
 # of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 
 #--------------------------------------------------------------------------
 # tk::Priv elements used in this file:
 #
 # afterId -		Token returned by "after" for autoscanning.
 # listboxPrev -		The last element to be selected or deselected
 #			during a selection operation.
 # listboxSelection -	All of the items that were selected before the
 #			current selection operation (such as a mouse
 #			drag) started;  used to cancel an operation.
 #--------------------------------------------------------------------------
 
 #-------------------------------------------------------------------------
 # The code below creates the default class bindings for listboxes.
 #-------------------------------------------------------------------------
 
 # Note: the check for existence of %W below is because this binding
 # is sometimes invoked after a window has been deleted (e.g. because
 # there is a double-click binding on the widget that deletes it).  Users
 # can put "break"s in their bindings to avoid the error, but this check
 # makes that unnecessary.
 
 bind Listbox <1> {
     if {[winfo exists %W]} {
 	tk::ListboxBeginSelect %W [%W index @%x,%y] 1
     }
 }
 
 # Ignore double clicks so that users can define their own behaviors.
 # Among other things, this prevents errors if the user deletes the
 # listbox on a double click.
 
 bind Listbox <Double-1> {
     # Empty script
 }
 
 bind Listbox <B1-Motion> {
     set tk::Priv(x) %x
     set tk::Priv(y) %y
     tk::ListboxMotion %W [%W index @%x,%y]
 }
 bind Listbox <ButtonRelease-1> {
     tk::CancelRepeat
     %W activate @%x,%y
 }
 bind Listbox <Shift-1> {
     tk::ListboxBeginExtend %W [%W index @%x,%y]
 }
 bind Listbox <Control-1> {
     tk::ListboxBeginToggle %W [%W index @%x,%y]
 }
 bind Listbox <B1-Leave> {
     set tk::Priv(x) %x
     set tk::Priv(y) %y
     tk::ListboxAutoScan %W
 }
 bind Listbox <B1-Enter> {
     tk::CancelRepeat
 }
 
 bind Listbox <<PrevLine>> {
     tk::ListboxUpDown %W -1
 }
 bind Listbox <<SelectPrevLine>> {
     tk::ListboxExtendUpDown %W -1
 }
 bind Listbox <<NextLine>> {
     tk::ListboxUpDown %W 1
 }
 bind Listbox <<SelectNextLine>> {
     tk::ListboxExtendUpDown %W 1
 }
 bind Listbox <<PrevChar>> {
     %W xview scroll -1 units
 }
 bind Listbox <<PrevWord>> {
     %W xview scroll -1 pages
 }
 bind Listbox <<NextChar>> {
     %W xview scroll 1 units
 }
 bind Listbox <<NextWord>> {
     %W xview scroll 1 pages
 }
 bind Listbox <Prior> {
     %W yview scroll -1 pages
     %W activate @0,0
 }
 bind Listbox <Next> {
     %W yview scroll 1 pages
     %W activate @0,0
 }
 bind Listbox <Control-Prior> {
     %W xview scroll -1 pages
 }
 bind Listbox <Control-Next> {
     %W xview scroll 1 pages
 }
 bind Listbox <<LineStart>> {
     %W xview moveto 0
 }
 bind Listbox <<LineEnd>> {
     %W xview moveto 1
 }
 bind Listbox <Control-Home> {
     %W activate 0
     %W see 0
     %W selection clear 0 end
     %W selection set 0
     tk::FireListboxSelectEvent %W
 }
 bind Listbox <Control-Shift-Home> {
     tk::ListboxDataExtend %W 0
 }
 bind Listbox <Control-End> {
     %W activate end
     %W see end
     %W selection clear 0 end
     %W selection set end
     tk::FireListboxSelectEvent %W
 }
 bind Listbox <Control-Shift-End> {
     tk::ListboxDataExtend %W [%W index end]
 }
 bind Listbox <<Copy>> {
     if {[selection own -displayof %W] eq "%W"} {
 	clipboard clear -displayof %W
 	clipboard append -displayof %W [selection get -displayof %W]
     }
 }
 bind Listbox <space> {
     tk::ListboxBeginSelect %W [%W index active]
 }
 bind Listbox <<Invoke>> {
     tk::ListboxBeginSelect %W [%W index active]
 }
 bind Listbox <Select> {
     tk::ListboxBeginSelect %W [%W index active]
 }
 bind Listbox <Control-Shift-space> {
     tk::ListboxBeginExtend %W [%W index active]
 }
 bind Listbox <Shift-Select> {
     tk::ListboxBeginExtend %W [%W index active]
 }
 bind Listbox <Escape> {
     tk::ListboxCancel %W
 }
 bind Listbox <<SelectAll>> {
     tk::ListboxSelectAll %W
 }
 bind Listbox <<SelectNone>> {
     if {[%W cget -selectmode] ne "browse"} {
 	%W selection clear 0 end
         tk::FireListboxSelectEvent %W
     }
 }
 
 # Additional Tk bindings that aren't part of the Motif look and feel:
 
 bind Listbox <2> {
     %W scan mark %x %y
 }
 bind Listbox <B2-Motion> {
     %W scan dragto %x %y
 }
 
 # The MouseWheel will typically only fire on Windows and Mac OS X.
 # However, someone could use the "event generate" command to produce
 # one on other platforms.
 
 if {[tk windowingsystem] eq "aqua"} {
     bind Listbox <MouseWheel> {
         %W yview scroll [expr {- (%D)}] units
     }
     bind Listbox <Option-MouseWheel> {
         %W yview scroll [expr {-10 * (%D)}] units
     }
     bind Listbox <Shift-MouseWheel> {
         %W xview scroll [expr {- (%D)}] units
     }
     bind Listbox <Shift-Option-MouseWheel> {
         %W xview scroll [expr {-10 * (%D)}] units
     }
 } else {
     bind Listbox <MouseWheel> {
         %W yview scroll [expr {- (%D / 120) * 4}] units
     }
     bind Listbox <Shift-MouseWheel> {
         %W xview scroll [expr {- (%D / 120) * 4}] units
     }
 }
 
 if {"x11" eq [tk windowingsystem]} {
     # Support for mousewheels on Linux/Unix commonly comes through mapping
     # the wheel to the extended buttons.  If you have a mousewheel, find
     # Linux configuration info at:
     #	http://linuxreviews.org/howtos/xfree/mouse/
     bind Listbox <4> {
 	if {!$tk_strictMotif} {
 	    %W yview scroll -5 units
 	}
     }
     bind Listbox <Shift-4> {
 	if {!$tk_strictMotif} {
 	    %W xview scroll -5 units
 	}
     }
     bind Listbox <5> {
 	if {!$tk_strictMotif} {
 	    %W yview scroll 5 units
 	}
     }
     bind Listbox <Shift-5> {
 	if {!$tk_strictMotif} {
 	    %W xview scroll 5 units
 	}
     }
 }
 
 # ::tk::ListboxBeginSelect --
 #
 # This procedure is typically invoked on button-1 presses.  It begins
 # the process of making a selection in the listbox.  Its exact behavior
 # depends on the selection mode currently in effect for the listbox;
 # see the Motif documentation for details.
 #
 # Arguments:
 # w -		The listbox widget.
 # el -		The element for the selection operation (typically the
 #		one under the pointer).  Must be in numerical form.
 
 proc ::tk::ListboxBeginSelect {w el {focus 1}} {
     variable ::tk::Priv
     if {[$w cget -selectmode] eq "multiple"} {
 	if {[$w selection includes $el]} {
 	    $w selection clear $el
 	} else {
 	    $w selection set $el
 	}
     } else {
 	$w selection clear 0 end
 	$w selection set $el
 	$w selection anchor $el
 	set Priv(listboxSelection) {}
 	set Priv(listboxPrev) $el
     }
     tk::FireListboxSelectEvent $w
     # check existence as ListboxSelect may destroy us
     if {$focus && [winfo exists $w] && [$w cget -state] eq "normal"} {
 	focus $w
     }
 }
 
 # ::tk::ListboxMotion --
 #
 # This procedure is called to process mouse motion events while
 # button 1 is down.  It may move or extend the selection, depending
 # on the listbox's selection mode.
 #
 # Arguments:
 # w -		The listbox widget.
 # el -		The element under the pointer (must be a number).
 
 proc ::tk::ListboxMotion {w el} {
     variable ::tk::Priv
     if {$el == $Priv(listboxPrev)} {
 	return
     }
     set anchor [$w index anchor]
     switch [$w cget -selectmode] {
 	browse {
 	    $w selection clear 0 end
 	    $w selection set $el
 	    set Priv(listboxPrev) $el
 	    tk::FireListboxSelectEvent $w
 	}
 	extended {
 	    set i $Priv(listboxPrev)
 	    if {$i eq ""} {
 		set i $el
 		$w selection set $el
 	    }
 	    if {[$w selection includes anchor]} {
 		$w selection clear $i $el
 		$w selection set anchor $el
 	    } else {
 		$w selection clear $i $el
 		$w selection clear anchor $el
 	    }
 	    if {![info exists Priv(listboxSelection)]} {
 		set Priv(listboxSelection) [$w curselection]
 	    }
 	    while {($i < $el) && ($i < $anchor)} {
 		if {[lsearch $Priv(listboxSelection) $i] >= 0} {
 		    $w selection set $i
 		}
 		incr i
 	    }
 	    while {($i > $el) && ($i > $anchor)} {
 		if {[lsearch $Priv(listboxSelection) $i] >= 0} {
 		    $w selection set $i
 		}
 		incr i -1
 	    }
 	    set Priv(listboxPrev) $el
 	    tk::FireListboxSelectEvent $w
 	}
     }
 }
 
 # ::tk::ListboxBeginExtend --
 #
 # This procedure is typically invoked on shift-button-1 presses.  It
 # begins the process of extending a selection in the listbox.  Its
 # exact behavior depends on the selection mode currently in effect
 # for the listbox;  see the Motif documentation for details.
 #
 # Arguments:
 # w -		The listbox widget.
 # el -		The element for the selection operation (typically the
 #		one under the pointer).  Must be in numerical form.
 
 proc ::tk::ListboxBeginExtend {w el} {
     if {[$w cget -selectmode] eq "extended"} {
 	if {[$w selection includes anchor]} {
 	    ListboxMotion $w $el
 	} else {
 	    # No selection yet; simulate the begin-select operation.
 	    ListboxBeginSelect $w $el
 	}
     }
 }
 
 # ::tk::ListboxBeginToggle --
 #
 # This procedure is typically invoked on control-button-1 presses.  It
 # begins the process of toggling a selection in the listbox.  Its
 # exact behavior depends on the selection mode currently in effect
 # for the listbox;  see the Motif documentation for details.
 #
 # Arguments:
 # w -		The listbox widget.
 # el -		The element for the selection operation (typically the
 #		one under the pointer).  Must be in numerical form.
 
 proc ::tk::ListboxBeginToggle {w el} {
     variable ::tk::Priv
     if {[$w cget -selectmode] eq "extended"} {
 	set Priv(listboxSelection) [$w curselection]
 	set Priv(listboxPrev) $el
 	$w selection anchor $el
 	if {[$w selection includes $el]} {
 	    $w selection clear $el
 	} else {
 	    $w selection set $el
 	}
 	tk::FireListboxSelectEvent $w
     }
 }
 
 # ::tk::ListboxAutoScan --
 # This procedure is invoked when the mouse leaves an entry window
 # with button 1 down.  It scrolls the window up, down, left, or
 # right, depending on where the mouse left the window, and reschedules
 # itself as an "after" command so that the window continues to scroll until
 # the mouse moves back into the window or the mouse button is released.
 #
 # Arguments:
 # w -		The entry window.
 
 proc ::tk::ListboxAutoScan {w} {
     variable ::tk::Priv
     if {![winfo exists $w]} return
     set x $Priv(x)
     set y $Priv(y)
     if {$y >= [winfo height $w]} {
 	$w yview scroll 1 units
     } elseif {$y < 0} {
 	$w yview scroll -1 units
     } elseif {$x >= [winfo width $w]} {
 	$w xview scroll 2 units
     } elseif {$x < 0} {
 	$w xview scroll -2 units
     } else {
 	return
     }
     ListboxMotion $w [$w index @$x,$y]
     set Priv(afterId) [after 50 [list tk::ListboxAutoScan $w]]
 }
 
 # ::tk::ListboxUpDown --
 #
 # Moves the location cursor (active element) up or down by one element,
 # and changes the selection if we're in browse or extended selection
 # mode.
 #
 # Arguments:
 # w -		The listbox widget.
 # amount -	+1 to move down one item, -1 to move back one item.
 
 proc ::tk::ListboxUpDown {w amount} {
     variable ::tk::Priv
     $w activate [expr {[$w index active] + $amount}]
     $w see active
     switch [$w cget -selectmode] {
 	browse {
 	    $w selection clear 0 end
 	    $w selection set active
 	    tk::FireListboxSelectEvent $w
 	}
 	extended {
 	    $w selection clear 0 end
 	    $w selection set active
 	    $w selection anchor active
 	    set Priv(listboxPrev) [$w index active]
 	    set Priv(listboxSelection) {}
 	    tk::FireListboxSelectEvent $w
 	}
     }
 }
 
 # ::tk::ListboxExtendUpDown --
 #
 # Does nothing unless we're in extended selection mode;  in this
 # case it moves the location cursor (active element) up or down by
 # one element, and extends the selection to that point.
 #
 # Arguments:
 # w -		The listbox widget.
 # amount -	+1 to move down one item, -1 to move back one item.
 
 proc ::tk::ListboxExtendUpDown {w amount} {
     variable ::tk::Priv
     if {[$w cget -selectmode] ne "extended"} {
 	return
     }
     set active [$w index active]
     if {![info exists Priv(listboxSelection)]} {
 	$w selection set $active
 	set Priv(listboxSelection) [$w curselection]
     }
     $w activate [expr {$active + $amount}]
     $w see active
     ListboxMotion $w [$w index active]
 }
 
 # ::tk::ListboxDataExtend
 #
 # This procedure is called for key-presses such as Shift-KEndData.
 # If the selection mode isn't multiple or extend then it does nothing.
 # Otherwise it moves the active element to el and, if we're in
 # extended mode, extends the selection to that point.
 #
 # Arguments:
 # w -		The listbox widget.
 # el -		An integer element number.
 
 proc ::tk::ListboxDataExtend {w el} {
     set mode [$w cget -selectmode]
     if {$mode eq "extended"} {
 	$w activate $el
 	$w see $el
         if {[$w selection includes anchor]} {
 	    ListboxMotion $w $el
 	}
     } elseif {$mode eq "multiple"} {
 	$w activate $el
 	$w see $el
     }
 }
 
 # ::tk::ListboxCancel
 #
 # This procedure is invoked to cancel an extended selection in
 # progress.  If there is an extended selection in progress, it
 # restores all of the items between the active one and the anchor
 # to their previous selection state.
 #
 # Arguments:
 # w -		The listbox widget.
 
 proc ::tk::ListboxCancel w {
     variable ::tk::Priv
     if {[$w cget -selectmode] ne "extended"} {
 	return
     }
     set first [$w index anchor]
     set last $Priv(listboxPrev)
     if {$last eq ""} {
 	# Not actually doing any selection right now
 	return
     }
     if {$first > $last} {
 	set tmp $first
 	set first $last
 	set last $tmp
     }
     $w selection clear $first $last
     while {$first <= $last} {
 	if {[lsearch $Priv(listboxSelection) $first] >= 0} {
 	    $w selection set $first
 	}
 	incr first
     }
     tk::FireListboxSelectEvent $w
 }
 
 # ::tk::ListboxSelectAll
 #
 # This procedure is invoked to handle the "select all" operation.
 # For single and browse mode, it just selects the active element.
 # Otherwise it selects everything in the widget.
 #
 # Arguments:
 # w -		The listbox widget.
 
 proc ::tk::ListboxSelectAll w {
     set mode [$w cget -selectmode]
     if {$mode eq "single" || $mode eq "browse"} {
 	$w selection clear 0 end
 	$w selection set active
     } else {
 	$w selection set 0 end
     }
     tk::FireListboxSelectEvent $w
 }
 
 # ::tk::FireListboxSelectEvent
 #
 # Fire the <<ListboxSelect>> event if the listbox is not in disabled
 # state.
 #
 # Arguments:
 # w -		The listbox widget.
 
 proc ::tk::FireListboxSelectEvent w {
     if {[$w cget -state] eq "normal"} {
         event generate $w <<ListboxSelect>>
     }
 }