UI view inheritance - one last time
mikael last edited by
Some recent conversations prompted one last try at the topic of not being able to inherit from UI module classes. Inheritance being useful if you want to code in the object-oriented style.
So here's a little thing to import, inheritable.py. It provides an inheritable duplicate of every UI view (and other classes).
A silly example, a Button that changes the tint color every time you click it:
import inheritable import random class TintButton(inheritable.Button): def __init__(self, **kwargs): self.super().__init__(**kwargs) # Note this self.action = self.set_random_tint def set_random_tint(self, sender): self.tint_color = tuple([random.random() for i in range(3)]) btn = TintButton(title='Click me')
Note the use of
self.superinstead of just
super. This is the only 'syntactic price' we have to make for the inheritable views.
btn, above, is still a ui.Button if you check its
type. This has the benefit of being compatible with all other UI code, without adding any unnecessary 'container' layers to your view hierarchy.
A slightly more useful example that adds a margin to a view, demonstrating overriding the
class MarginView(inheritable.View): def __init__(self, margin=20): self.margin = margin def size_to_fit(self): self.super().size_to_fit() self.frame = self.frame.inset(-self.margin, -self.margin)
Multiple inheritance works normally, with the first superclass listed taking precedence for
__init__. The resulting UI type will also be that of the first superclass.
class MultiButton(TintButton, MarginView): pass btn = MultiButton(flex='RTBL', tint_color='red', background_color='white', margin=50, title='Click me') print(type(btn)) == ui.Button # True
__init__is not called, but
margingets set on the object anyway because of the normal
uimodule practice of setting any extra arguments as attributes of the instance.)
These examples are included at the end of the file (linked at the top).
Would be really interesting to hear if this approach works for your use case, or whether there are some surprises related to some of the UI classes.