(Kivy Python) 在 .py 文件中按下按钮切换屏幕
(Kivy Python) Switching Screens on Button Press Inside .py file
我了解到使用 on_release 在 .kv 文件中切换屏幕相对容易。但是,我想保留在 .py 文件中创建的按钮,因此我不想使用此方法。我已完成以下操作以添加按下第 14 个按钮时发生的功能。当在程序中按下按钮时,什么也没有发生。尝试将屏幕的其他名称 sm.current 抛出错误: "kivy.uix.screenmanager.ScreenManagerException: No Screen with name "InputScreen" 当按下第 14 个按钮时。"
# Kivy Formatting
kv_text='''\
<MyScreenManager>:
LandingScreen:
InputScreen:
<InputScreen@Screen>:
name: 'input_sc'
AnchorLayout:
id: anchor_1
<LandingScreen@Screen>:
name: 'landing_sc'
GridLayout:
id: grid_1
cols: 5
height: 480
width: 800
spacing: 25, 20
padding: 25,25
'''
# Screen Manager
class MyScreenManager(ScreenManager):
pass
# Main screen with button layout
class LandingScreen(Screen):
def __init__(self, **kwargs):
super(LandingScreen, self).__init__(**kwargs)
self.buttons = [] # add references to all buttons here
Clock.schedule_once(self._finish_init)
# IDs have to be used here because they cannot be applied until widget initialized
def _finish_init(self, dt):
self.ids.grid_1.cols = 5
# Loop to make 15 different buttons on screen
for x in range(15):
self.buttons.append(Button(text='button {}'.format(x)))
self.ids.grid_1.add_widget(self.buttons[x])
self.buttons[x].background_normal = 'YOUTUBE.png'
def SwitchScreen(self,*args):
sm.current = 'input_sc'
sm = ScreenManager()
sm.add_widget(InputScreen(name='input_sc'))
sm.add_widget(LandingScreen(name='landing'))
self.buttons[14].bind(on_release=SwitchScreen)
# Input screen
class InputScreen(Screen):
pass
class MySubApp(App):
def build(self):
return MyScreenManager()
def main():
Builder.load_string(kv_text)
app = MySubApp()
app.run()
if __name__ == '__main__':
main()
如果有人能帮助我理解我当前逻辑中的漏洞,我将不胜感激。谢谢。
每个屏幕都有一个 manager
属性,为您提供所用 ScreenManager
的实例。您只需要使用它来引用 ScreemManager
实例并使用其 current
方法:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.button import Button
from kivy.clock import Clock
# Kivy Formatting
kv_text='''\
<MyScreenManager>:
LandingScreen:
InputScreen:
<InputScreen@Screen>:
name: 'input_sc'
AnchorLayout:
id: anchor_1
Button:
text: 'Hello'
<LandingScreen@Screen>:
name: 'landing_sc'
GridLayout:
id: grid_1
cols: 5
height: 480
width: 800
spacing: 25, 20
padding: 25,25
'''
# Screen Manager
class MyScreenManager(ScreenManager):
pass
# Main screen with button layout
class LandingScreen(Screen):
def __init__(self, **kwargs):
super(LandingScreen, self).__init__(**kwargs)
self.buttons = [] # add references to all buttons here
Clock.schedule_once(self._finish_init)
# IDs have to be used here because they cannot be applied until widget initialized
def _finish_init(self, dt):
self.ids.grid_1.cols = 5
# Loop to make 15 different buttons on screen
for x in range(15):
self.buttons.append(Button(text='button {}'.format(x)))
self.ids.grid_1.add_widget(self.buttons[x])
self.buttons[x].background_normal = 'YOUTUBE.png'
self.buttons[14].bind(on_release=self.switch_screen)
def switch_screen(self, *args):
self.manager.current = 'input_sc'
# Input screen
class InputScreen(Screen):
pass
class MySubApp(App):
def build(self):
return MyScreenManager()
def main():
Builder.load_string(kv_text)
app = MySubApp()
app.run()
if __name__ == '__main__':
main()
我了解到使用 on_release 在 .kv 文件中切换屏幕相对容易。但是,我想保留在 .py 文件中创建的按钮,因此我不想使用此方法。我已完成以下操作以添加按下第 14 个按钮时发生的功能。当在程序中按下按钮时,什么也没有发生。尝试将屏幕的其他名称 sm.current 抛出错误: "kivy.uix.screenmanager.ScreenManagerException: No Screen with name "InputScreen" 当按下第 14 个按钮时。"
# Kivy Formatting
kv_text='''\
<MyScreenManager>:
LandingScreen:
InputScreen:
<InputScreen@Screen>:
name: 'input_sc'
AnchorLayout:
id: anchor_1
<LandingScreen@Screen>:
name: 'landing_sc'
GridLayout:
id: grid_1
cols: 5
height: 480
width: 800
spacing: 25, 20
padding: 25,25
'''
# Screen Manager
class MyScreenManager(ScreenManager):
pass
# Main screen with button layout
class LandingScreen(Screen):
def __init__(self, **kwargs):
super(LandingScreen, self).__init__(**kwargs)
self.buttons = [] # add references to all buttons here
Clock.schedule_once(self._finish_init)
# IDs have to be used here because they cannot be applied until widget initialized
def _finish_init(self, dt):
self.ids.grid_1.cols = 5
# Loop to make 15 different buttons on screen
for x in range(15):
self.buttons.append(Button(text='button {}'.format(x)))
self.ids.grid_1.add_widget(self.buttons[x])
self.buttons[x].background_normal = 'YOUTUBE.png'
def SwitchScreen(self,*args):
sm.current = 'input_sc'
sm = ScreenManager()
sm.add_widget(InputScreen(name='input_sc'))
sm.add_widget(LandingScreen(name='landing'))
self.buttons[14].bind(on_release=SwitchScreen)
# Input screen
class InputScreen(Screen):
pass
class MySubApp(App):
def build(self):
return MyScreenManager()
def main():
Builder.load_string(kv_text)
app = MySubApp()
app.run()
if __name__ == '__main__':
main()
如果有人能帮助我理解我当前逻辑中的漏洞,我将不胜感激。谢谢。
每个屏幕都有一个 manager
属性,为您提供所用 ScreenManager
的实例。您只需要使用它来引用 ScreemManager
实例并使用其 current
方法:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.button import Button
from kivy.clock import Clock
# Kivy Formatting
kv_text='''\
<MyScreenManager>:
LandingScreen:
InputScreen:
<InputScreen@Screen>:
name: 'input_sc'
AnchorLayout:
id: anchor_1
Button:
text: 'Hello'
<LandingScreen@Screen>:
name: 'landing_sc'
GridLayout:
id: grid_1
cols: 5
height: 480
width: 800
spacing: 25, 20
padding: 25,25
'''
# Screen Manager
class MyScreenManager(ScreenManager):
pass
# Main screen with button layout
class LandingScreen(Screen):
def __init__(self, **kwargs):
super(LandingScreen, self).__init__(**kwargs)
self.buttons = [] # add references to all buttons here
Clock.schedule_once(self._finish_init)
# IDs have to be used here because they cannot be applied until widget initialized
def _finish_init(self, dt):
self.ids.grid_1.cols = 5
# Loop to make 15 different buttons on screen
for x in range(15):
self.buttons.append(Button(text='button {}'.format(x)))
self.ids.grid_1.add_widget(self.buttons[x])
self.buttons[x].background_normal = 'YOUTUBE.png'
self.buttons[14].bind(on_release=self.switch_screen)
def switch_screen(self, *args):
self.manager.current = 'input_sc'
# Input screen
class InputScreen(Screen):
pass
class MySubApp(App):
def build(self):
return MyScreenManager()
def main():
Builder.load_string(kv_text)
app = MySubApp()
app.run()
if __name__ == '__main__':
main()