# button.tcl --
#
# This file defines the default bindings for Tk label, button,
# checkbutton, and radiobutton widgets.
#
# @(#) button.tcl 1.15 95/03/08 09:55:26
#
# Copyright (c) 1992-1994 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.
#

# tkButtonBind --
# This procedure is invoked the first time the mouse enters a button,
# checkbutton, or radiobutton, or any one of these widgets receives
# the input focus.  It creates all of the class bindings for the widgets.
#
# Arguments:
# w -		The widget that was just entered or just received
#		the input focus.
# 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.

proc tkButtonBind {w {event {}}} {
    if {$event == "Enter"} {
	tkButtonEnter $w
    }

    # Standard Motif bindings:

    bind Button <FocusIn> {}
    bind Button <Enter> {
	tkButtonEnter %W
    }
    bind Button <Leave> {
	tkButtonLeave %W
    }
    bind Button <1> {
	tkButtonDown %W
    }
    bind Button <ButtonRelease-1> {
	tkButtonUp %W
    }
    bind Button <space> {
	tkButtonInvoke %W
    }

    bind Checkbutton <FocusIn> {}
    bind Checkbutton <Enter> {
	tkButtonEnter %W
    }
    bind Checkbutton <Leave> {
	tkButtonLeave %W
    }
    bind Checkbutton <1> {
	tkCheckRadioInvoke %W
    }
    bind Checkbutton <space> {
	tkCheckRadioInvoke %W
    }

    bind Radiobutton <FocusIn> {}
    bind Radiobutton <Enter> {
	tkButtonEnter %W
    }
    bind Radiobutton <Leave> {
	tkButtonLeave %W
    }
    bind Radiobutton <1> {
	tkCheckRadioInvoke %W
    }
    bind Radiobutton <space> {
	tkCheckRadioInvoke %W
    }
}

# tkButtonEnter --
# The procedure below is invoked when the mouse pointer enters a
# button widget.  It records the button we're in and changes the
# state of the button to active unless the button is disabled.
#
# Arguments:
# w -		The name of the widget.

proc tkButtonEnter {w} {
    global tkPriv
    if {[$w cget -state] != "disabled"} {
	$w config -state active
	if {$tkPriv(buttonWindow) == $w} {
	    $w configure -state active -relief sunken
	}
    }
    set tkPriv(window) $w
}

# tkButtonLeave --
# The procedure below is invoked when the mouse pointer leaves a
# button widget.  It changes the state of the button back to
# inactive.  If we're leaving the button window with a mouse button
# pressed (tkPriv(buttonWindow) == $w), restore the relief of the
# button too.
#
# Arguments:
# w -		The name of the widget.

proc tkButtonLeave w {
    global tkPriv
    if {[$w cget -state] != "disabled"} {
	$w config -state normal
    }
    if {$w == $tkPriv(buttonWindow)} {
	$w configure -relief $tkPriv(relief)
    }
    set tkPriv(window) ""
}

# tkButtonDown --
# The procedure below is invoked when the mouse button is pressed in
# a button widget.  It records the fact that the mouse is in the button,
# saves the button's relief so it can be restored later, and changes
# the relief to sunken.
#
# Arguments:
# w -		The name of the widget.

proc tkButtonDown w {
    global tkPriv
    set tkPriv(relief) [lindex [$w config -relief] 4]
    if {[$w cget -state] != "disabled"} {
	set tkPriv(buttonWindow) $w
	$w config -relief sunken
    }
}

# tkButtonUp --
# The procedure below is invoked when the mouse button is released
# in a button widget.  It restores the button's relief and invokes
# the command as long as the mouse hasn't left the button.
#
# Arguments:
# w -		The name of the widget.

proc tkButtonUp w {
    global tkPriv
    if {$w == $tkPriv(buttonWindow)} {
	set tkPriv(buttonWindow) ""
	$w config -relief $tkPriv(relief)
	if {($w == $tkPriv(window))
		&& ([$w cget -state] != "disabled")} {
	    uplevel #0 [list $w invoke]
	}
    }
}

# tkButtonInvoke --
# The procedure below is called when a button is invoked through
# the keyboard.  It simulate a press of the button via the mouse.
#
# Arguments:
# w -		The name of the widget.

proc tkButtonInvoke w {
    if {[$w cget -state] != "disabled"} {
	set oldRelief [$w cget -relief]
	set oldState [$w cget -state]
	$w configure -state active -relief sunken
	update idletasks
	after 100
	$w configure -state $oldState -relief $oldRelief
	uplevel #0 [list $w invoke]
    }
}

# tkCheckRadioInvoke --
# The procedure below is invoked when the mouse button is pressed in
# a checkbutton or radiobutton widget, or when the widget is invoked
# through the keyboard.  It invokes the widget if it
# isn't disabled.
#
# Arguments:
# w -		The name of the widget.

proc tkCheckRadioInvoke w {
    if {[$w cget -state] != "disabled"} {
	uplevel #0 [list $w invoke]
    }
}
