在Kivy应用程序中获取textinput值

Question

Python/Kivy的新手试图通过一个输入框，一个ok按钮和一个应该在单击ok按钮时更改文本的标签来构建一个测试应用程序。但相反，我得到'NameError：全球名称'txt1'未定义'。我究竟做错了什么？

# import Kivy 
import kivy 
import random 

from kivy.app import App 
from kivy.uix.button import Button 
from kivy.uix.boxlayout import BoxLayout 
from kivy.uix.label import Label 
from kivy.uix.textinput import TextInput 

# my app 
class MyApp(App): 
# layout 
    def build(self): 
     layout = BoxLayout(padding=10, orientation='vertical') 
     btn1 = Button(text="OK") 
     btn1.bind(on_press=self.buttonClicked) 
     layout.add_widget(btn1) 
     lbl1 = Label(text="test") 
     layout.add_widget(lbl1) 
     txt1 = TextInput(text='', multiline=False) 
     layout.add_widget(txt1) 
     return layout 

# button click function 
    def buttonClicked(self,btn): 
     lbl1.text = "You wrote " + txt1.text 

# run app 
if __name__ == "__main__": 
    MyApp().run() 

Answer 1

使用self.txt1, self.lbl1等。

class MyApp(App): 
# layout 
    def build(self): 
     layout = BoxLayout(padding=10, orientation='vertical') 
     btn1 = Button(text="OK") 
     btn1.bind(on_press=self.buttonClicked) 
     layout.add_widget(btn1) 
     self.lbl1 = Label(text="test") 
     layout.add_widget(self.lbl1) 
     self.txt1 = TextInput(text='', multiline=False) 
     layout.add_widget(self.txt1) 
     return layout 

# button click function 
    def buttonClicked(self,btn): 
     self.lbl1.text = "You wrote " + self.txt1.text 

# run app 
if __name__ == "__main__": 
    MyApp().run() 
# join all items in a list into 1 big string 

使用：

def buttonClicked(self,btn): 
     lbl1.text = "You wrote " + txt1.text <- only exists in the build method