如何定义当用户在 TextInput 中输入文本并在 Kivy 中按 Enter 时会发生什么？

Question

我正在尝试使用 Kivy 和 Python 创建一个简单的聊天机器人应用程序 UI，但我被困在了第一阶段。 如何访问 BoxLayout 内的 TextInput 小部件以获取其内容？

我了解到，只要您在 TextInput 上按“Enter”，就会调用函数 on_text_validate()。但是，下面的这段代码似乎不起作用。

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.label import Label
from kivy.uix.textinput import TextInput
from kivy.uix.screenmanager import Screen, ScreenManager, FadeTransition
from kivy.uix.scrollview import ScrollView
from kivy.properties import StringProperty
from kivy.lang import Builder

Builder.load_string('''
#:import AnchorLayout kivy.uix.anchorlayout
#:import Layout kivy.uix.layout
<ChatBotScreen>:
    BoxLayout:
        orientation: 'vertical'

        ScrollView:
            Label:
                size_hint_y: None
                height: self.texture_size[1]
                text_size: self.width, None
                botOutput: root.botOutput
        ScrollView:
            Label:
                size_hint_y: None
                height: self.texture_size[1]
                text_size: self.width, None
                userInput: root.userInput
        TextInput:
            id: ti_userinput
            multiline: False
''')

class ChatBotScreen(Screen):
    userInput = StringProperty()
    botOutput = StringProperty()

    def on_text_validate(self):
        text_input_userInput = self.ids['ti_userinput'].text
        self.ids['ti_userinput'].text = ''
        print(text_input_userInput)

    def UserInput(self):
        pass
    def BotOutput(self):
        pass

sm = ScreenManager(transition=FadeTransition())
sm.add_widget(ChatBotScreen(name='mainchat'))    

class MyApp(App):
    def build(self):
        return sm

请指导我。

Answer 1

你的问题是on_text_validate不是Screen类的方法，而是TextInput的方法，所以你永远不会调用ChatBotScreen类的on_text_validate，你可以做的是从TextInput 的on_text_validate 事件调用该方法：

Builder.load_string('''
#:import AnchorLayout kivy.uix.anchorlayout
#:import Layout kivy.uix.layout
<ChatBotScreen>:
    BoxLayout:
        orientation: 'vertical'

        ScrollView:
            Label:
                size_hint_y: None
                height: self.texture_size[1]
                text_size: self.width, None
                botOutput: root.botOutput
        ScrollView:
            Label:
                size_hint_y: None
                height: self.texture_size[1]
                text_size: self.width, None
                userInput: root.userInput
        TextInput:
            id: ti_userinput
            multiline: False
            on_text_validate: root.on_text_validate()
''')

class ChatBotScreen(Screen):
    userInput = StringProperty()
    botOutput = StringProperty()

    def on_text_validate(self):
        text_input_userInput = self.ids['ti_userinput'].text
        self.ids['ti_userinput'].text = ''
        print(text_input_userInput)

sm = ScreenManager(transition=FadeTransition())
sm.add_widget(ChatBotScreen(name='mainchat'))    

class MyApp(App):
    def build(self):
        return sm