python kivy屏幕配置

Question

main.py file  
from kivymd.app import MDApp
from kivy.lang import Builder
class Hero(MDApp):
    def build(self):
        return Builder.load_file("stackoverflow.kv")
Hero().run()

以上是main.py文件 请大家帮帮我

stackoverflow.kv 文件

ScreenManager:
    id: screenmanager
    Screen:
        id: accountscreen
        name: "screen1"
        BoxLayout:
            oreintation: "vertical"
            MDGridLayout:
                cols:1## Heading ##
               MDLabel:
                    text: "[color=00FF00]Sign In[/color]"
                    bold:True
                    markup:True
                    halign: "center"
                    valign: "middle"
                MDTextField:
                    id: username
                    padding: "30dp"
                    spacing: "30dp"
                    hint_text:"User Name or Email"
                    pos_hint: {"center_x":.5,"center_y":.5}
                MDTextField:
                    id:password
                    padding: "20dp"
                    spacing: "20dp"
                    hint_text:"Password"
                MDRectangleFlatButton:
                    text:"Sign In"
                    padding: "16dp"
                    spacing: "16dp"
                    halign: "center"
                    pos_hint: {"center_x":.9,"center_y":.5}
                    on_press: app.root.current="screen2"

                BoxLayout:
                    oreintation: "vertical"
    Screen:
        id: welcome_screen
        name: "screen2"
        MDLabel:
            text: "welcome"
            valign: "middle"
            halign: "center"

每当我打开应用程序时，我都会看到登录屏幕，如何使用配置 ini 文件保存用户信息并清除屏幕，请帮助我？？？？

Answer 1

这是你代码的一个版本，它使用Config 来做你想做的事：

import os
from kivymd.app import MDApp
from kivy.lang import Builder

class Hero(MDApp):
    def build(self):
        sm = Builder.load_file("stackoverflow.kv")
        self.load_my_config()
        sm.current = self.initial_screen
        return sm

    def build_config(self, config):
        # Make sure that the config has at least default entries that we need
        config.setdefaults('app', {
            'startup_screen': 'screen1',
        })

    def get_application_config(self):
        # This defines the path and name where the ini file is located
        return str(os.path.join(os.path.expanduser('~'), 'Hero.ini'))

    def on_stop(self):
        # save the config when the app exits
        self.save_config()

    def save_config(self):
        # this writes the data we want to save to the config

        # set the data in the config
        self.config.set('app', 'startup_screen', 'screen2')

        # write the config file
        self.config.write()

    def load_my_config(self):
        # extract our saved data from the config (it has already been read)
        self.initial_screen = self.config.get('app', 'startup_screen', fallback='screen1')

Hero().run()

在kv 文件中，我会添加一个调用以在按下Sign In 按钮时保存配置：

            MDRectangleFlatButton:
                text:"Sign In"
                padding: "16dp"
                spacing: "16dp"
                halign: "center"
                pos_hint: {"center_x":.9,"center_y":.5}
                on_press:
                    app.root.current="screen2"
                    app.save_config()