Kivy: Recycleview -Aufrufe __init__ Bevor die Daten festgelegt werden, und die Größe auf Standardwerte zurücksetzen sche ⇐ Python

[Anonymous]

Ich habe eine Recycleview. Die ViewClass ist eine Klasse, die die Schaltfläche erweitert. Ein anfängliches grundlegendes Beispiel, das ich erstellt habe, ist, außer 1. Einige Initialisierungsdaten werden nicht angezeigt, und 2. Die Schaltflächen werden geändert (bis (100, 100) - ich vermute, das ist ein Standard -Standard). < /P>

Code: Select all

class InventoryIngredientButton(Button):
count = NumericProperty(None)
display_count = StringProperty(None)

def __init__(self, inventory_ingredient: InventoryIngredient = ing1, **kwargs):
print("init is being called")
super().__init__(
background_normal=inventory_ingredient.ingredient.icon_img,
text=inventory_ingredient.ingredient.display_name,
size_hint=(None, None),
size=(200, 200),
**kwargs)

def use(self):
self.count -= 1
self.display_count = str(self.count)

def on_count(self, instance, value):
# print size for debugging
print("count is %s and size is %s" % (value, self.size))
if value == 0:
self.disabled = True

# for debugging
def on_size(self, instance, value):
print("Size changed to value %s for button %s" % (value, self.count))

< /code>
class RV(RecycleView):
def __init__(self):
super().__init__()

# 1. count is respected, inventory_ingredient is not:
# 2. If you add “’size’: (200, 200)” to the dictionaries then buttons aren’t resized:
self.data = [{'inventory_ingredient': ing2, 'count': 6}, {'count': 3, 'inventory_ingredient': ing1}]
< /code>
.tutorial_listview.kv file:

pos: self.x, self.y
pos_hint: None, None
count: 1
on_press: root.use()

Label:
text: str(root.count)
pos: root.x-10,root.y-10
pos_hint: None, None

:
viewclass: 'InventoryIngredientButton'
RecycleBoxLayout:
rows: 2
cols: 5
size_hint: 1, 1
pos_hint: 0, 0
< /code>
Runner included for completeness:
class RecycleTutorialApp(App):
def build(self):
return RV()

if __name__ == "__main__":
Builder.load_file('tutorial_listview.kv')
RecycleTutorialApp().run()
< /code>
The print logs indicate that the buttons are initialized with default values. Then, when self.data is set, count is overwritten to the displayed value. However, unless I explicitly set size, size=(100,100) seems to reset next and resizes the button. inventory_ingredient

wird auch ignoriert, weil __init__ bereits aufgerufen wurde.init is being called and type is Lemon (Lemon is the default)
Size changed to value [200, 200] for button None
count is 1 and size is [200, 200]
count is 0 and size is [200, 200]
Size changed to value [100, 100] for button 0
init is being called and type is Lemon
Size changed to value [200, 200] for button None
count is 1 and size is [200, 200]
Size changed to value [100, 100] for button 1
< /code>
I suspect that changing inventory_ingredient to an ObjectProperty would allow it to get updated on-the-fly, but I didn’t want all of the automatically generated event listeners that would come with that because it shouldn't change post-initialization. And obviously I can also force size=(200,200) every time I change data. But both those solutions feel like a shallow workaround because I’m brand new to Kivy and lack a fuller understanding of the behavior that’s happening.
PS In RV.__init__, I tried 1. setting self.data before calling super().__init__() and 2. passing super().__init__(data=data, **kwargs) but neither worked.