Adds an activatable widget to the action area of a Dialog, connecting a signal handler that will emit the response signal on the dialog when the widget is activated.
The widget is appended to the end of the dialog’s action area. If you want to add a non-activatable widget, simply pack it into the
action_area field of the Dialog struct.
| this |
a Dialog |
| child |
an activatable widget |
| response_id |
response ID for |