Edit: /usr/share/tk8.6/ttk/button.tcl (2978B)
#
# Bindings for Buttons, Checkbuttons, and Radiobuttons.
#
# Notes:
, only control the "pressed"
# state; widgets remain "active" if the pointer is dragged out.
# This doesn't seem to be conventional, but it's a nice way
# to provide extra feedback while the grab is active.
# (If the button is released off the widget, the grab deactivates and
# we get a event then, which turns off the "active" state)
#
# Normally, and events are
# delivered to the widget which received the initial
# event. However, Tk [grab]s (#1223103) and menu interactions
# (#1222605) can interfere with this. To guard against spurious
# events, the binding only sets
# the pressed state if the button is currently active.
#
namespace eval ttk::button {}
bind TButton { %W instate !disabled {%W state active} }
bind TButton { %W state !active }
bind TButton { ttk::button::activate %W }
bind TButton <> { ttk::button::activate %W }
bind TButton \
{ %W instate !disabled { ttk::clickToFocus %W; %W state pressed } }
bind TButton \
{ %W instate pressed { %W state !pressed; %W instate !disabled { %W invoke } } }
bind TButton \
{ %W state !pressed }
bind TButton \
{ %W instate {active !disabled} { %W state pressed } }
# Checkbuttons and Radiobuttons have the same bindings as Buttons:
#
ttk::copyBindings TButton TCheckbutton
ttk::copyBindings TButton TRadiobutton
# ...plus a few more:
bind TRadiobutton { ttk::button::RadioTraverse %W -1 }
bind TRadiobutton { ttk::button::RadioTraverse %W +1 }
# bind TCheckbutton { %W select }
# bind TCheckbutton { %W deselect }
# activate --
# Simulate a button press: temporarily set the state to 'pressed',
# then invoke the button.
#
proc ttk::button::activate {w} {
$w instate disabled { return }
set oldState [$w state pressed]
update idletasks; after 100 ;# block event loop to avoid reentrancy
$w state $oldState
$w invoke
}
# RadioTraverse -- up/down keyboard traversal for radiobutton groups.
# Set focus to previous/next radiobutton in a group.
# A radiobutton group consists of all the radiobuttons with
# the same parent and -variable; this is a pretty good heuristic
# that works most of the time.
#
proc ttk::button::RadioTraverse {w dir} {
set group [list]
foreach sibling [winfo children [winfo parent $w]] {
if { [winfo class $sibling] eq "TRadiobutton"
&& [$sibling cget -variable] eq [$w cget -variable]
&& ![$sibling instate disabled]
} {
lappend group $sibling
}
}
if {![llength $group]} { # Shouldn't happen, but can.
return
}
set pos [expr {([lsearch -exact $group $w] + $dir) % [llength $group]}]
tk::TabToWindow [lindex $group $pos]
}