This section covers the use of the Kivy properties. A Kivy property triggers an event every time we modify it. There are different types of properties, from the simple
StringProperty to much more complex versions such as
ObjectProperty. For example, if we define a
text, then an
on_text event is going to be triggered each time the text is modified.
Once we define a Kivy property, Kivy internally creates an event associated with that property. The property event is referenced adding the prefix
on_ to the name of the property. For example, the
on_translation method (line 246) is associated with
ListProperty in line 219 called ...