python screenmanager (kivy)

Question

`from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.gridlayout import GridLayout
from kivy.uix.screenmanager import ScreenManager, Screen

class Login(Screen):
    def main(self):
        layout = GridLayout()
        def btn():
            sm.switch_to(Screen(name='account'))
        self.bt = Button(text='tela 1',
                         size_hint=(None,None),
                         size=(592,86),
                         pos=(50,50), on_press=btn,
                         background_color=(1,0,0,0))
        layout.add_widget(self.bt)
        return layout
    
class Account(Screen):
    def main2(self):
        lt = GridLayout()
        def btnn():
            sm.switch_to(Screen(name='login'))
        self.btt = Button(text='telaa 2',
                         size_hint=(None,None),
                         size=(592,86),
                         pos=(50, 50), on_press=btnn,
                         background_color=(1,0,0,0))
        lt.add_widget(self.btt)
        return lt

sm = ScreenManager()
sm.add_widget(Login(name='login'))
sm.add_widget(Account(name='account'))

class TestApp(App):

    def build(self):
        return sm

if _name_ == '_main_':
    TestApp().run()

`我今天入手了kivy，不過只是個路過的小說，沒打算學kivy語言。

我在網上看到的所有關於屏幕管理器的教程都使用kivy語言。 如何僅使用 python 滾動瀏覽 2 個屏幕？ 我試圖將 kivy 語言翻譯成 python，但我得到的只是黑屏。

Answer 1

這是使用 Python 代碼（不是 kv 語言）創建帶有Button的Screen的最小示例，該按鈕在屏幕管理器中更改屏幕。

from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.button import Button
from kivy.uix.label import Label
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.boxlayout import BoxLayout

# Declare both screens

class MenuScreen(Screen):
    
    def __init__(self, **kwargs):
        super().__init__(**kwargs)

        self.layout = BoxLayout()
        self.add_widget(self.layout)

        self.label = Label(text='Menu Screen')        
        self.layout.add_widget(self.label)

        self.button = Button(text='Go To Settings')
        self.button.bind(on_press=self.change_screen)
        self.layout.add_widget(self.button)
        
    def change_screen(self, event):
        #sm.current = 'settings'
        self.manager.transition.direction = 'up'
        self.manager.transition.duration = 3 # 3 seconds
        self.manager.current = 'settings'
        
class SettingsScreen(Screen):
    
    def __init__(self, **kwargs):
        super().__init__(**kwargs)

        self.layout = FloatLayout()
        self.add_widget(self.layout)

        self.label = Label(text='Settings Screen')        
        self.layout.add_widget(self.label)

        self.button = Button(text='Go To Menu', size_hint=(.5, .10), pos=(20, 20))
        self.button.bind(on_press=self.change_screen)
        self.layout.add_widget(self.button)

    def change_screen(self, event):
        #sm.current = 'menu'
        self.manager.transition.direction = 'right'
        self.manager.transition.duration = 0.5 # 0.5 second
        self.manager.current = 'menu'

# Create the screen manager

sm = ScreenManager()
sm.add_widget(MenuScreen(name='menu'))
sm.add_widget(SettingsScreen(name='settings'))


class TestApp(App):

    def build(self):
        return sm


if __name__ == '__main__':
    TestApp().run()

基於文檔屏幕管理器中的示例（使用 kv 語言）

Answer 2

你必須學習kv語言。

Kivy 語言是一種專用於描述用戶界面和交互的語言。 您可以將此語言與 Qt 的 QML ( http://qt.nokia.com ) 進行比較，但我們包含了諸如規則定義之類的新概念，因此您可能知道一些新概念。