path: root/Master/perltl/site/lib/Tk/Scale.pm

# Converted from scale.tcl --
#
# This file defines the default bindings for Tk scale widgets.
#
# @(#) scale.tcl 1.3 94/12/17 16:05:23
#
# Copyright (c) 1994 The Regents of the University of California.
# Copyright (c) 1994 Sun Microsystems, Inc.
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.

package Tk::Scale;

use vars qw($VERSION);
$VERSION = '3.012'; # $Id: //depot/Tk8/Scale/Scale.pm#12 $

use Tk qw($XS_VERSION);
use AutoLoader;

use base  qw(Tk::Widget);

Construct Tk::Widget 'Scale';

bootstrap Tk::Scale;

sub Tk_cmd { \&Tk::scale }

Tk::Methods('coords','get','identify','set');


import Tk qw(Ev);

#
# Bind --
# This procedure below invoked the first time the mouse enters a
# scale widget or a scale widget receives the input focus. It creates
# all of the class bindings for scales.
#
# Arguments:
# event - Indicates which event caused the procedure to be invoked
# (Enter or FocusIn). It is used so that we can carry out
# the functions of that event in addition to setting up
# bindings.
sub ClassInit
{
 my ($class,$mw) = @_;

 $mw->bind($class,'<Enter>',['Enter',Ev('x'),Ev('y')]);
 $mw->bind($class,'<Motion>',['Activate',Ev('x'),Ev('y')]);
 $mw->bind($class,'<Leave>','Leave');

 $mw->bind($class,'<1>',['ButtonDown',Ev('x'),Ev('y')]);
 $mw->bind($class,'<B1-Motion>',['Drag',Ev('x'),Ev('y')]);
 $mw->bind($class,'<B1-Leave>','NoOp');
 $mw->bind($class,'<B1-Enter>','NoOp');
 $mw->bind($class,'<ButtonRelease-1>',['ButtonUp',Ev('x'),Ev('y')]);

 $mw->bind($class,'<2>',['ButtonDown',Ev('x'),Ev('y')]);
 $mw->bind($class,'<B2-Motion>',['Drag',Ev('x'),Ev('y')]);
 $mw->bind($class,'<B2-Leave>','NoOp');
 $mw->bind($class,'<B2-Enter>','NoOp');
 $mw->bind($class,'<ButtonRelease-2>',['ButtonUp',Ev('x'),Ev('y')]);

 $mw->bind($class,'<Control-1>',['ControlPress',Ev('x'),Ev('y')]);

 $mw->bind($class,'<Up>',['Increment','up','little','noRepeat']);
 $mw->bind($class,'<Down>',['Increment','down','little','noRepeat']);
 $mw->bind($class,'<Left>',['Increment','up','little','noRepeat']);
 $mw->bind($class,'<Right>',['Increment','down','little','noRepeat']);

 $mw->bind($class,'<Control-Up>',['Increment','up','big','noRepeat']);
 $mw->bind($class,'<Control-Down>',['Increment','down','big','noRepeat']);
 $mw->bind($class,'<Control-Left>',['Increment','up','big','noRepeat']);
 $mw->bind($class,'<Control-Right>',['Increment','down','big','noRepeat']);

 $mw->bind($class,'<Home>',['set',Ev('cget','-from')]);
 $mw->bind($class,'<End>',['set',Ev('cget','-to')]);
 return $class;
}

1;

__END__

# Activate --
# This procedure is invoked to check a given x-y position in the
# scale and activate the slider if the x-y position falls within
# the slider.
#
# Arguments:
# w - The scale widget.
# x, y - Mouse coordinates.
sub Activate
{
 my $w = shift;
 my $x = shift;
 my $y = shift;
 return if ($w->cget('-state') eq 'disabled');
 my $ident = $w->identify($x,$y);
 if (defined($ident) && $ident eq 'slider')
  {
   $w->configure(-state => 'active')
  }
 else
  {
   $w->configure(-state => 'normal')
  }
}

sub Leave
{
 my ($w) = @_;
 $w->configure('-activebackground',$w->{'activeBg'}) if ($Tk::strictMotif);
 $w->configure('-state','normal')  if ($w->cget('-state') eq 'active');
}

sub Enter
{
 my ($w,$x,$y) = @_;
 if ($Tk::strictMotif)
  {
   $w->{'activeBg'} = $w->cget('-activebackground');
   $w->configure('-activebackground',$w->cget('-background'));
  }
 $w->Activate($x,$y);
}

sub ButtonUp
{
 my ($w,$x,$y) = @_;
 $w->CancelRepeat();
 $w->EndDrag();
 $w->Activate($x,$y)
}


# ButtonDown --
# This procedure is invoked when a button is pressed in a scale. It
# takes different actions depending on where the button was pressed.
#
# Arguments:
# w - The scale widget.
# x, y - Mouse coordinates of button press.
sub ButtonDown
{
 my $w = shift;
 my $x = shift;
 my $y = shift;
 $Tk::dragging = 0;
 $el = $w->identify($x,$y);
 return unless ($el);
 if ($el eq 'trough1')
  {
   $w->Increment('up','little','initial')
  }
 elsif ($el eq 'trough2')
  {
   $w->Increment('down','little','initial')
  }
 elsif ($el eq 'slider')
  {
   $Tk::dragging = 1;
   my @coords = $w->coords();
   $Tk::deltaX = $x-$coords[0];
   $Tk::deltaY = $y-$coords[1];
  }
}
# Drag --
# This procedure is called when the mouse is dragged with
# mouse button 1 down. If the drag started inside the slider
# (i.e. the scale is active) then the scale's value is adjusted
# to reflect the mouse's position.
#
# Arguments:
# w - The scale widget.
# x, y - Mouse coordinates.
sub Drag
{
 my $w = shift;
 my $x = shift;
 my $y = shift;
 if (!$Tk::dragging)
  {
   return;
  }
 $w->set($w->get($x-$Tk::deltaX,$y-$Tk::deltaY))
}
# EndDrag --
# This procedure is called to end an interactive drag of the
# slider.  It just marks the drag as over.
# Arguments:
# w - The scale widget.
sub EndDrag
{
 my $w = shift;
 if (!$Tk::dragging)
  {
   return;
  }
 $Tk::dragging = 0;
}
# Increment --
# This procedure is invoked to increment the value of a scale and
# to set up auto-repeating of the action if that is desired. The
# way the value is incremented depends on the "dir" and "big"
# arguments.
#
# Arguments:
# w - The scale widget.
# dir - "up" means move value towards -from, "down" means
# move towards -to.
# big - Size of increments: "big" or "little".
# repeat - Whether and how to auto-repeat the action: "noRepeat"
# means don't auto-repeat, "initial" means this is the
# first action in an auto-repeat sequence, and "again"
# means this is the second repetition or later.
sub Increment
{
 my $w = shift;
 my $dir = shift;
 my $big = shift;
 my $repeat = shift;
 my $inc;
 if ($big eq 'big')
  {
   $inc = $w->cget('-bigincrement');
   if ($inc == 0)
    {
     $inc = abs(($w->cget('-to')-$w->cget('-from')))/10.0
    }
   if ($inc < $w->cget('-resolution'))
    {
     $inc = $w->cget('-resolution')
    }
  }
 else
  {
   $inc = $w->cget('-resolution')
  }
 if (($w->cget('-from') > $w->cget('-to')) ^ ($dir eq 'up'))
  {
   $inc = -$inc
  }
 $w->set($w->get()+$inc);
 if ($repeat eq 'again')
  {
   $w->RepeatId($w->after($w->cget('-repeatinterval'),'Increment',$w,$dir,$big,'again'));
  }
 elsif ($repeat eq 'initial')
  {
   $w->RepeatId($w->after($w->cget('-repeatdelay'),'Increment',$w,$dir,$big,'again'));
  }
}
# ControlPress --
# This procedure handles button presses that are made with the Control
# key down. Depending on the mouse position, it adjusts the scale
# value to one end of the range or the other.
#
# Arguments:
# w - The scale widget.
# x, y - Mouse coordinates where the button was pressed.
sub ControlPress
{
 my ($w,$x,$y) = @_;
 my $el = $w->identify($x,$y);
 return unless ($el);
 if ($el eq 'trough1')
  {
   $w->set($w->cget('-from'))
  }
 elsif ($el eq 'trough2')
  {
   $w->set($w->cget('-to'))
  }
}