2022-01-29-python-gtk-scale-value-changed-event-handler.md (1131B)
1 title: Handling Python/GTK's GtkScale value-changed event. 2 date: 2022-01-29 3 4 It took me way too long, but now I know how to handle the value-changed event of GtkScale. 5 6 In Glade: 7 8 1. Create a GtkScale widget. We will ID it `foo_scale`. 9 2. In the `Signals -> GtkRange -> value-changed` line change the `Handler` 10 field to something sensible like `on_foo_scale_value_changed`. That will 11 be the name of the handler. 12 3. Make a new Adjustment in: 13 14 ``` 15 General -> 16 Adjustment -> 17 (little pen button in the field) -> 18 Choose a [sic] Adjustment in this project -> 19 New 20 ``` 21 22 4. Rename the adjustment to something sensible like `foo_adjustment` and set 23 the `Value`, `Minimum Value`, `Maximum Value`, etc. Those are kind of self 24 explanatory… 25 5. In Python, your handler will be called with a single argument - the signal 26 emitting object, which is the GtkScale object itself. It has a method, 27 `get_value()`, used to get its current value: 28 29 ```python 30 def on_foo_scale_value_changed(emitter): 31 scale_value = emitter.get_value() 32 do_stuff_with_scale_value(scale_value) 33 ``` 34 35 Fin.