Hi there,

I have an application which needs to perform some action when a radio button is deselected. This is what happens when the radio button has previously been clicked, then another radio button is clicked.

The Tk::Radiobutton widget has a callback, -command, but this is only called when the button is clicked, i.e. selected. It is not called when a different button sharing the same -variable is clicked

I know it's possible to code a common subroutine for all the radio buttons in the group, but this is outside my control as I am trying to write a new composite widget (which by implication will not know about other radio buttons outside the widget, unless its -variable changes).

Presumably, there is some internal method in the widget that is called in order for the radio button to get visually unclicked. All I am after is access to this event as a callback, in the manner of -deselect_command below: 


my $foo;

for (qw/eenie meenie minie mo/) {
    $mw->Radiobutton(
         -text => $_,
         -command => sub { print "$_ selected\n" },
#        -deselect_command => sub { print "$_ unselected\n" },
         -variable => \$foo,
         -value => $_
    ) ->pack( -side => 'left');
}

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In reply to Need a callback for Tk radio button deselect by rinceWind

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