在第二个屏幕上显示输入

Question

我想在第二个屏幕Ausgabe的 label 中显示来自屏幕Eingabe的文本字段输入。 我不明白 kivy 语言的参考。 谢谢：我总是得到一个错误：

self or 'ausgabe' is not defined

如何从第二个屏幕 class Ausgabe的第一个屏幕输入的文本字段中访问值并在第二个屏幕的 label 中显示结果？

主要.py：

from kivy.lang import Builder
from kivymd.app import MDApp
from kivymd.theming import ThemeManager
from kivymd.uix.screen import MDScreen
from kivy.properties import ObjectProperty, StringProperty
from kivy.garden.matplotlib.backend_kivyagg import FigureCanvasKivyAgg
from kivy.uix.widget import Widget
from kivy.core.window import Window
import matplotlib.pyplot as plt
from kivymd.uix.datatables import MDDataTable
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from time import sleep
from kivy.metrics import dp

class Eingabe(MDScreen):
    kapital = ObjectProperty(None)
    text1 = ObjectProperty(None)
    t = ''
    def btn(self):
        print(self.kapital.text)
        self.text1.text = str('Endsumme: ' + self.kapital.text)
    
        t = self.kapital.text
    pass


class Ausgabe(MDScreen):
     #tabelle = ObjectProperty(None)
    eingabe1 = ausgabe.manager.get_screen('eingabe')
    self.ausgabe.text = str(eingabe1.t)
    pass


class WindowManager(ScreenManager):
    pass

Window.size = (540, 960)

class main2App(MDApp):
    title = "Sparplanrechner"

    def build(self):
        #self.theme_cls.primary_palette = "Blue" 
        self.theme_cls.theme_style = "Light"
        return Builder.load_file("main2.kv")


if __name__ == "__main__":
    main2App().run()

main2.kv：

WindowManager:
    Eingabe:
    Ausgabe:

<Eingabe>:
    name: "eingabe"
    
    kapital: kapital
    rate: rate
    zins: zins
    zeit: zeit
    text1: text1
    ausgabe: ausgabe
    
    MDGridLayout:
        #adaptive_size: True
        md_bg_color: 1,1,1,1
        padding: dp(40)
        spacing: dp(40)
        cols: 1
        
            
      
        MDTextField:
            hint_text: "Steuerfreibetrag"
            id: zeit
            font_size: sp(20)
            helper_text: "Steuerfreibetrag (i.d.R. 801€)"
            helper_text_mode: "on_focus"
            mode: "rectangle"
            fill_color: 0, 0, 0, 0            
        
        MDLabel:
            text: ''
            id: text1
            halign: "center"
            valign: 'middle'
            theme_text_color: "Custom"
            text_color: 207,95,54, 1
            font_style: "H6"
            bold: True
            
        MDGridLayout:
            #adaptive_size: True
            md_bg_color: 1,1,1,1
            padding: dp(40)
            spacing: dp(40)
            cols: 2
            
            MDRaisedButton:
                text: "Berechnen"
                #text_color: 0, 0, 0, 1
                font_size: "20sp"
                pos_hint: {'center_x':0.5,'center_y':.5}
                on_release: root.btn()        
                
            MDRaisedButton:
                text: "Zeige Deteils"
                font_size: "20sp"
                pos_hint: {'center_x':0.5,'center_y':.5}
                on_release:
                    app.root.current = "ausgabe"
                    root.manager.transition.direction = "left"

<Ausgabe>:
    name: "ausgabe"
    #tabelle: tabelle
    
    #MDDataTable:
     #   id: tabelle
        #column_data:[("Column 1", dp(30)),("Column 4", dp(30))]
    MDLabel:
            text: ''
            id: ausgabe
            halign: "center"
            valign: 'middle'
            theme_text_color: "Custom"
            text_color: 207,95,54, 1
            font_style: "H6"
            bold: True

    MDRaisedButton:
        text: "Go Back"
        on_release:
            app.root.current = "eingabe"
            root.manager.transition.direction = "right"

Answer 1

您可以使用Ausgabe Screen的on_enter()方法执行此操作，如下所示：

class Ausgabe(MDScreen):
    def on_enter(self, *args):
        self.ids.ausgabe.text = self.manager.get_screen('eingabe').zeit.text

on_enter()方法在屏幕显示时被调用，因此它会在Ausgabe Screen显示时更新MDLabel 。