[ CCode ( simple_generics = true ) ]
public void set_user_data<T> (owned T user_data)
Sets user_data on the frame and the DestroyNotify that
will be called when the frame is freed.
Allows to attach private data by the subclass to frames.
If a user_data was previously set, then the previous set notify will be called before the user_data
is replaced.
| this | |
| user_data |
private data |
| notify |