我试图创建一个使用Kivy DropDown
类的一个简单的例子。这是简单,点击主按钮,然后在下拉的2个按钮列表应该会出现。我不与.bind
使用的方法,所以这是我的代码:
import kivy
from kivy.app import App
from kivy.uix.dropdown import DropDown
from kivy.uix.button import Button
from kivy.uix.floatlayout import FloatLayout
dropdown = DropDown()
btn1 = Button(text = "attack")
btn2 = Button(text = "item")
dropdown.add_widget(btn1)
dropdown.add_widget(btn2)
class MainButton(Button):
def on_release(self):
super().on_release()
print("something")
dropdown.open(self)
class Layout(FloatLayout):
pass
btn = MainButton(text = "Hello")
class theApp(App):
def build(self):
layout = Layout()
layout.add_widget(btn)
btn.pos_hint = {'x': 0.5, 'y': 0.5}
btn.size_hint = (0.25, 0.25)
return layout
app = theApp()
app.run()
另一个问题,当我使用DropDown.open
方法的类方法之外,我得到EN错误:
import kivy
from kivy.app import App
from kivy.uix.dropdown import DropDown
from kivy.uix.button import Button
from kivy.uix.floatlayout import FloatLayout
dropdown = DropDown()
btn1 = Button(text = "attack")
btn2 = Button(text = "item")
dropdown.add_widget(btn1)
dropdown.add_widget(btn2)
btn = Button(text = "Hello")
class theApp(App):
def build(self):
layout = FloatLayout()
layout.add_widget(btn)
btn.pos_hint = {'x': 0.5, 'y': 0.5}
btn.size_hint = (0.25, 0.25)
dropdown.open(btn)
return layout
app = theApp()
app.run()
File "/usr/lib/python3/dist-packages/kivy/uix/dropdown.py", line 245, in open
'Cannot open a dropdown list on a hidden widget')
kivy.uix.dropdown.DropDownException: Cannot open a dropdown list on a hidden widget
为什么是这样?谢谢。
为什么你不能看到两个按钮,当你按下按钮MainButton
的理由是,你还没有设置每个按钮的高度。
试着给他们一个高度:
btn1 = Button(text = "attack")
btn1.size_hint_y = None
btn1.height = 44
btn2 = Button(text = "item")
btn2.size_hint_y = None
btn2.height = 44
dropdown.add_widget(btn1)
dropdown.add_widget(btn2)
这是我的手机上的输出:
点击该按钮之前:
点击该按钮后:
关于第二个问题,我认为你不能做到这一点build
方法内,因为layout
部件尚未返回。你可以创建一个新的方法并执行它,只要你按下按钮。
def build(self):
layout = FloatLayout()
layout.add_widget(btn)
btn.pos_hint = {'x': 0.5, 'y': 0.5}
btn.size_hint = (0.25, 0.25)
btn.on_release = self.showDropdown
return layout
def showDropdown(self):
dropdown.open(btn)