我是kivy的新手，目前正在尝试制作一个应用程序。我正在写这段代码，由于下拉菜单的原因，我需要从boxlayout开始，但之后我想在按下开始按钮时更改为Gridlayout。如果有人能给我一个灵魂的洗礼，我会非常感激。
Builder.load_string("""
<CustomDropDown>
Button:
text: "Nobara"
size_hint_y: None
height: 44
on_release: root.select("Nobara")
Button:
text: "Maki"
size_hint_y: None
height: 44
on_release: root.select("Maki")
""")
class CustomDropDown(DropDown):
pass
xy = ""
class MainApp(App):
def build(self):
self.startbutton = Button(text='Start',
size_hint=(.2, .2),
pos_hint={'center_x': .5, 'center_y': .5})
self.startbutton.bind(on_press=self.on_press_startbutton)
self.dropbutton = Button(text='Karakter',
size_hint=(.2, .2),
pos_hint={'center_x': .50, 'center_y': .5})
dropdown = CustomDropDown()
self.dropbutton.bind(on_release=dropdown.open)
dropdown.bind(on_select = lambda instance, x : setattr(self.dropbutton, 'text', x))
dropdown.bind(on_select = lambda instance, x : karaktervalasztas(x))
self.visszabutton = Button(text="Kilépés",
size_hint=(.2, .2),
pos_hint={'center_x': .5, 'center_y': .5})
self.visszabutton.bind(on_press=self.on_press_visszabutton)
"""self.huzasbutton = Button(text=f"Huzas: {len(pakli)}",
size_hint=(.2, .2),
pos_hint={'center_x': .5, 'center_y': .5})
self.huzasbutton.bind(on_press=self.on_press_kartyahuzas)"""
boxlayout = BoxLayout()
boxlayout.add_widget(self.startbutton)
boxlayout.add_widget(self.dropbutton)
return boxlayout
def on_press_startbutton(self, instance):
boxlayout = GridLayout(cols=10)
self.root.clear_widgets()
self.root.add_widget(self.visszabutton)
self.root.add_widget(Button(text=f"Huzas: {len(pakli)}", size_hint=(.2, .2), pos_hint={'center_x': .5, 'center_y': .5}, on_press=self.on_press_kartyahuzas))
self.root.add_widget(Button(text=f"Dobópakli: {len(dobopakli)}", size_hint=(.2, .2), pos_hint={'center_x': .5, 'center_y': .5}, on_press=self.on_press_dobopakli))
start()
for i in hand:
#self.root.add_widget(Button(text=str(i), on_press=lambda *args: self.on_press_kartya()))
self.root.add_widget(Button(size_hint=(.2, .2), background_normal=i+ '.jpg', on_press=self.on_press_kartya))
return boxlayout
为什么不从一开始就使用GridLayout？在您的build()方法中：
boxlayout = GridLayout(cols=2, size_hint_y=0.25)
然后，在您的on_press_startbutton():中
def on_press_startbutton(self, instance):
# boxlayout = GridLayout(cols=10)
self.root.clear_widgets()
self.root.cols = 10
self.root.size_hint_y = 1.0
self.root.add_widget(self.visszabutton)
.
.
.
并且CCD_ 4可以从CCD_。