toggled
The "toggled" signal is emitted when the toggled() method is called. This happens whenever the button is activated. As part of the response to the button classes' activating signal "clicked", the state of the toggle indicator is switched from GTK_STATE_ACTIVE to GTK_STATE_NORMAL or vice versa. Note that this state-switching has no relationship with the "toggled" signal itself.
Callback function
void callback(GtkToggleButton togglebutton);
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