#
# Utilities for widget implementations.
#
### Focus management.
#
# See also: #1516479
#
## ttk::takefocus --
# This is the default value of the "-takefocus" option
# for ttk::* widgets that participate in keyboard navigation.
#
# NOTES:
# tk::FocusOK (called by tk_focusNext) tests [winfo viewable]
# if -takefocus is 1, empty, or missing; but not if it's a
# script prefix, so we have to check that here as well.
#
#
proc ttk::takefocus {w} {
expr {[$w instate !disabled] && [winfo viewable $w]}
}
## ttk::GuessTakeFocus --
# This routine is called as a fallback for widgets
# with a missing or empty -takefocus option.
#
# It implements the same heuristics as tk::FocusOK.
#
proc ttk::GuessTakeFocus {w} {
# Don't traverse to widgets with '-state disabled':
#
if {![catch {$w cget -state} state] && $state eq "disabled"} {
return 0
}
# Allow traversal to widgets with explicit key or focus bindings:
#
if {[regexp {Key|Focus} [concat [bind $w] [bind [winfo class $w]]]]} {
return 1;
}
# Default is nontraversable:
#
return 0;
}
## ttk::traverseTo $w --
# Set the keyboard focus to the specified window.
#
proc ttk::traverseTo {w} {
set focus [focus]
if {$focus ne ""} {
event generate $focus <<TraverseOut>>
}
focus $w
event generate $w <<TraverseIn>>
}
## ttk::clickToFocus $w --
# Utility routine, used in <ButtonPress-1> bindings --
# Assign keyboard focus to the specified widget if -takefocus is enabled.
#
proc ttk::clickToFocus {w} {
if {[ttk::takesFocus $w]} { focus $w }
}
## ttk::takesFocus w --
# Test if the widget can take keyboard focus.
#
# See the description of the -takefocus option in options(n)
# for details.
#
proc ttk::takesFocus {w} {
if {![winfo viewable $w]} {
return 0
} elseif {[catch {$w cget -takefocus} takefocus]} {
return [GuessTakeFocus $w]
} else {
switch -- $takefocus {
"" { return [GuessTakeFocus $w] }
0 { return 0 }
1 { return 1 }
default {
return [expr {[uplevel #0 $takefocus [list $w]] == 1}]
}
}
}
}
## ttk::focusFirst $w --
# Return the first descendant of $w, in preorder traversal order,
# that can take keyboard focus, "" if none do.
#
# See also: tk_focusNext
#
proc ttk::focusFirst {w} {
if {[ttk::takesFocus $w]} {
return $w
}
foreach child [winfo children $w] {
if {[set c [ttk::focusFirst $child]] ne ""} {
return $c
}
}
return ""
}
### Grabs.
#
# Rules:
# Each call to [grabWindow $w] or [globalGrab $w] must be
# matched with a call to [releaseGrab $w] in LIFO order.
#
# Do not call [grabWindow $w] for a window that currently
# appears on the grab stack.
#
# See #1239190 and #1411983 for more discussion.
#
namespace eval ttk {
variable Grab ;# map: window name -> grab token
# grab token details:
# Two-element list containing:
# 1) a script to evaluate to restore the previous grab (if any);
# 2) a script to evaluate to restore the focus (if any)
}
## SaveGrab --
# Record current grab and focus windows.
#
proc ttk::SaveGrab {w} {
variable Grab
if {[info exists Grab($w)]} {
# $w is already on the grab stack.
# This should not happen, but bail out in case it does anyway:
#
return
}
set restoreGrab [set restoreFocus ""]
set grabbed [grab current $w]
if {[winfo exists $grabbed]} {
switch [grab status $grabbed] {
global { set restoreGrab [list grab -global $grabbed] }
local { set restoreGrab [list grab $grabbed] }
none { ;# grab window is really in a different interp }
}
}
set focus [focus]
if {$focus ne ""} {
set restoreFocus [list focus -force $focus]
}
set Grab($w) [list $restoreGrab $restoreFocus]
}
## RestoreGrab --
# Restore previous grab and focus windows.
# If called more than once without an intervening [SaveGrab $w],
# does nothing.
#
proc ttk::RestoreGrab {w} {
variable Grab
if {![info exists Grab($w)]} { # Ignore
return;
}
# The previous grab/focus window may have been destroyed,
# unmapped, or some other abnormal condition; ignore any errors.
#
foreach script $Grab($w) {
catch $script
}
unset Grab($w)
}
## ttk::grabWindow $w --
# Records the current focus and grab windows, sets an application-modal
# grab on window $w.
#
proc ttk::grabWindow {w} {
SaveGrab $w
grab $w
}
## ttk::globalGrab $w --
# Same as grabWindow, but sets a global grab on $w.
#
proc ttk::globalGrab {w} {
SaveGrab $w
grab -global $w
}
## ttk::releaseGrab --
# Release the grab previously set by [ttk::grabWindow]
# or [ttk::globalGrab].
#
proc ttk::releaseGrab {w} {
grab release $w
RestoreGrab $w
}
### Auto-repeat.
#
# NOTE: repeating widgets do not have -repeatdelay
# or -repeatinterval resources as in standard Tk;
# instead a single set of settings is applied application-wide.
# (TODO: make this user-configurable)
#
# (@@@ Windows seems to use something like 500/50 milliseconds
# @@@ for -repeatdelay/-repeatinterval)
#
namespace eval ttk {
variable Repeat
array set Repeat {
delay 300
interval 100
timer {}
script {}
}
}
## ttk::Repeatedly --
# Begin auto-repeat.
#
proc ttk::Repeatedly {args} {
variable Repeat
after cancel $Repeat(timer)
set script [uplevel 1 [list namespace code $args]]
set Repeat(script) $script
uplevel #0 $script
set Repeat(timer) [after $Repeat(delay) ttk::Repeat]
}
## Repeat --
# Continue auto-repeat
#
proc ttk::Repeat {} {
variable Repeat
uplevel #0 $Repeat(script)
set Repeat(timer) [after $Repeat(interval) ttk::Repeat]
}
## ttk::CancelRepeat --
# Halt auto-repeat.
#
proc ttk::CancelRepeat {} {
variable Repeat
after cancel $Repeat(timer)
}
### Bindings.
#
## ttk::copyBindings $from $to --
# Utility routine; copies bindings from one bindtag onto another.
#
proc ttk::copyBindings {from to} {
foreach event [bind $from] {
bind $to $event [bind $from $event]
}
}
### Mousewheel bindings.
#
# Platform inconsistencies:
#
# On X11, the server typically maps the mouse wheel to Button4 and Button5.
#
# On OSX, Tk generates sensible values for the %D field in <MouseWheel> events.
#
# On Windows, %D must be scaled by a factor of 120.
# In addition, Tk redirects mousewheel events to the window with
# keyboard focus instead of sending them to the window under the pointer.
# We do not attempt to fix that here, see also TIP#171.
#
# OSX conventionally uses Shift+MouseWheel for horizontal scrolling,
# and Option+MouseWheel for accelerated scrolling.
#
# The Shift+MouseWheel behavior is not conventional on Windows or most
# X11 toolkits, but it's useful.
#
# MouseWheel scrolling is accelerated on X11, which is conventional
# for Tk and appears to be conventional for other toolkits (although
# Gtk+ and Qt do not appear to use as large a factor).
#
## ttk::bindMouseWheel $bindtag $command...
# Adds basic mousewheel support to $bindtag.
# $command will be passed one additional argument
# specifying the mousewheel direction (-1: up, +1: down).
#
proc ttk::bindMouseWheel {bindtag callback} {
switch -- [tk windowingsystem] {
x11 {
bind $bindtag <ButtonPress-4> "$callback -1"
bind $bindtag <ButtonPress-5> "$callback +1"
}
win32 {
bind $bindtag <MouseWheel> [append callback { [expr {-(%D/120)}]}]
}
aqua {
bind $bindtag <MouseWheel> [append callback { [expr {-(%D)}]} ]
}
}
}
## Mousewheel bindings for standard scrollable widgets.
#
# Usage: [ttk::copyBindings TtkScrollable $bindtag]
#
# $bindtag should be for a widget that supports the
# standard scrollbar protocol.
#
switch -- [tk windowingsystem] {
x11 {
bind TtkScrollable <ButtonPress-4> { %W yview scroll -5 units }
bind TtkScrollable <ButtonPress-5> { %W yview scroll 5 units }
bind TtkScrollable <Shift-ButtonPress-4> { %W xview scroll -5 units }
bind TtkScrollable <Shift-ButtonPress-5> { %W xview scroll 5 units }
}
win32 {
bind TtkScrollable <MouseWheel> \
{ %W yview scroll [expr {-(%D/120)}] units }
bind TtkScrollable <Shift-MouseWheel> \
{ %W xview scroll [expr {-(%D/120)}] units }
}
aqua {
bind TtkScrollable <MouseWheel> \
{ %W yview scroll [expr {-(%D)}] units }
bind TtkScrollable <Shift-MouseWheel> \
{ %W xview scroll [expr {-(%D)}] units }
bind TtkScrollable <Option-MouseWheel> \
{ %W yview scroll [expr {-10*(%D)}] units }
bind TtkScrollable <Shift-Option-MouseWheel> \
{ %W xview scroll [expr {-10*(%D)}] units }
}
}
#*EOF*
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