问题：
如何在不使用 KV 语言的情况下使用 On-Press 事件更改 python 中动态创建的按钮的屏幕？
目标：
能够通过单击动态创建的按钮导航到新屏幕，
[不需要在 Kivy 中创建按钮，并且仍然可以在 Python 和 Kivy 中使用 Screenmanager（不确定您是否必须在整个程序中坚持使用 Python 或 Kivy？）
我已经尝试过的事情：
- 使用
button_share.bind(on_press = self.changer)，然后这个：
def changer(self,*args):
ScreenManager()
screenmanager.current = 'MainScreen'
但我得到了错误ScreenManagerException: No Screen with name "MainScreen".
怀疑：
我认为这是因为我正在创建一个 ScreenManager 的新实例，而不是引用现有的实例。为了解决这个问题，我考虑在 App 类中实例化 Screenmanager()，然后在我的按钮def changer(self, *args)方法中引用该实例化，但如果它不是我实际用于所有屏幕的 ScreenManager，那将毫无用处。这些都是用 KV 语言定义的。如果没有大量的努力，我将无法将它们全部切换。
- 使用：
button_share.bind(on_press=partial(app.sm.setter('current'), (app.sm, "MainScreen")))`
但我在这里得到的错误是ValueError: ScreenManager.current accept only str
下面是一个完全可运行的示例：
注意：在这个例子中，我想点击“继续编辑”按钮，然后点击“测试 1”、“测试 2”或“测试 3”按钮，让它带我到另一个屏幕。
蟒蛇代码：
from kivy.app import App
# kivy.require("1.10.0")
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.clock import Clock
from kivy.uix.widget import Widget
#from kivy.base import runTouchApp
from kivy.properties import StringProperty, ObjectProperty, NumericProperty
from functools import partial
class ScrollableLabelDataEntryInstructions(BoxLayout):
pass
class NewGarageScreen(Screen):
pass
class ContinueEditingScreen(Screen):
pass
class GarageNameBoxLayout(BoxLayout):
box_share2 = ObjectProperty()
sm = ScreenManager()
def __init__(self, **kwargs):
super(GarageNameBoxLayout, self).__init__(**kwargs)
self.orientation = "vertical"
Clock.schedule_interval(self.create_button, 5)
def create_button(self, *args):
self.box_share2.clear_widgets()
app = App.get_running_app()
#put GarageNameStartList data into app class, then pull from it in this class
top_button_share = 1.1
color = (.4, .4, .4, 1)
for i in range(len(app.GarageNameStartList)):
top_button_share -= .4
id_ = app.GarageNameStartList[i]
button_share = Button(background_normal='',
background_color = color,
id = id_,
pos_hint = {"x": 0, "top": top_button_share},
size_hint_y = None,
height = 60,
font_size = 30,
text = app.GarageNameStartList[i])
button_share.bind(on_press = self.changer)
#button_share.bind(on_press=partial(app.sm.setter('current'), (app.sm, "MainScreen")))
self.box_share2.add_widget(button_share)
def changer(self,*args):
ScreenManager()
#app = App.get_running_app()
screenmanager.current = 'MainScreen'
class BackHomeWidget(Widget):
pass
class MainScreen(Screen):
pass
class AnotherScreen(Screen):
pass
class ScreenManagement(ScreenManager):
pass
presentation = Builder.load_file("example_on_press.kv")
class MainApp(App):
GarageNameStartList = ["Test1", "Test2", "Test3"]
def Update_GarageNameStartList(self, *args):
self.GarageNameStartList = ["Test1", "Test2", "Test3"]
def build(self):
return presentation
if __name__ == "__main__":
MainApp().run()
千伏代码：
#: import FadeTransition kivy.uix.screenmanager.FadeTransition
ScreenManagement:
transition: FadeTransition()
MainScreen:
AnotherScreen:
NewGarageScreen:
ContinueEditingScreen:
<SmallNavButton@Button>:
font_size: 32
size: 125, 50
color: 0,1,0,1
<MedButton@Button>:
font_size: 30
size_hint: 0.25, 0.1
color: 0,1,0,1
<BackHomeWidget>:
SmallNavButton:
on_release: app.root.current = "main"
text: "Home"
pos: root.x, root.top - self.height
<MainScreen>:
name: "main"
FloatLayout:
MedButton:
on_release: app.root.current = "edit"
text: "Edit"
pos_hint: {"x":0.3728, "top": 0.4}
<AnotherScreen>:
name: "edit"
BackHomeWidget:
SmallNavButton:
on_release: app.root.current = "main"
text: "Back"
pos: root.x, root.top - (2.25*(self.height))
FloatLayout:
MedButton:
on_release: app.root.current = "continueediting"
text: "Continue Editing"
pos_hint: {"x":0.25, "top": 0.6}
MedButton:
on_release: app.root.current = "newgarage"
text: "Create New"
pos_hint: {"x":0.3728, "top": 0.4}
<NewGarageScreen>:
name: "newgarage"
BackHomeWidget:
SmallNavButton:
on_release: app.root.current = "edit"
text: "Back"
pos: root.x, root.top - (2.25*(self.height))
FloatLayout:
MedButton:
text: "1. Groundfloor"
pos_hint: {"x":0, "top": 0.6}
<GarageNameBoxLayout>:
box_share2: box_share2
ScrollView:
GridLayout:
id: box_share2
cols: 1
size_hint_y: None
size_hint_x: 0.5
spacing: 5
padding: 130
height: self.minimum_height
canvas:
Color:
rgb: 0, 0, 0
Rectangle:
pos: self.pos
size: self.size
<ContinueEditingScreen>:
name: "continueediting"
GarageNameBoxLayout:
BackHomeWidget:
SmallNavButton:
on_release: app.root.current = "edit"
text: "Back"
pos: root.x, root.top - (2.25*(self.height))