Sets label_widget as the widget that will be used as the label
for button. If label_widget is NULL the "label" property is used
as label. If "label" is also NULL, the label in the stock item
determined by the "stock_id" property is used as label. If
"stock_id" is also NULL, button does not have a label.
Since 2.4
Sets label_widget as the widget that will be used as the label for button. If label_widget is NULL the "label" property is used as label. If "label" is also NULL, the label in the stock item determined by the "stock_id" property is used as label. If "stock_id" is also NULL, button does not have a label. Since 2.4