KivyMD中KV语言绑定按钮与get_texts函数报错求助

错误原因 #

报错'FloatLayout' object has no attribute 'get_texts'是因为kv文件中root指代的是最外层的FloatLayout实例，而get_texts方法定义在你的App（MDApp子类）中，FloatLayout自然没有这个方法，导致调用失败。

解决方法 #

1. 用app调用App类的方法 #

在kv文件中，app是MDApp实例的内置引用，直接用它来调用get_texts即可：
修改按钮的on_release属性：

MDRaisedButton:
    # 其余属性保持不变
    on_release: app.get_texts()

2. 修正代码拼写错误 #

你的main.py里存在一处拼写错误：self.root.ids.passoword中的passoword应该改为password（和kv文件里的输入框id一致），否则会找不到对应的文本框。修正后的代码片段：

def get_texts(self):
    user_text_field = self.root.ids.username
    user_text = user_text_field.text

    password_text_field = self.root.ids.password  # 修正拼写错误
    password_text = password_text_field.text

    quantity_text_field = self.root.ids.quantity
    quantity_text = quantity_text_field.text

    return user_text, password_text, quantity_text

完整修改后的代码 #

main.py #

from kivymd.tools.hotreload.app import MDApp
from kivy.lang import Builder
from kivy.core.window import Window

class App(MDApp):
    def get_texts(self):
        user_text_field = self.root.ids.username
        user_text = user_text_field.text

        password_text_field = self.root.ids.password
        password_text = password_text_field.text

        quantity_text_field = self.root.ids.quantity
        quantity_text = quantity_text_field.text

        # 可添加打印测试，确认内容获取正常
        print(f"用户名: {user_text}, 密码: {password_text}, 数量: {quantity_text}")
        return user_text, password_text, quantity_text

    KV_FILES = ["app.kv"]
    DEBUG = True
    def build_app(self):
        Window.size = (320, 370)
        Window.resizable = 0
        return Builder.load_file("app.kv")

App().run()

app.kv #

FloatLayout: #:kivy !
    Image:
        source: "src/images/instagram_bg.jpg"
        allow_stretch: True
        keep_ratio: False
    MDLabel: 
        text: "Comment Bot"
        color: "#FFFFFF"
        font_size: "38sp"
        font_name: "font.ttf"
        pos_hint: {"center_x": 0.59, "center_y": 0.9}
    MDIcon:
        icon: "instagram"
        color: "#FFFFFF"
        font_size: "45sp"
        pos_hint: {"center_x": 0.85, "center_y": 0.90}
    MDTextField:
        id: username
        line_color_normal: "#ffffff"
        line_color_focus: "#ffffff"
        hint_text: "Nome de usuário ou e-mail"
        size_hint_x: .8
        pos_hint: {"center_x": 0.5, "center_y": 0.75}
        mode: "rectangle"
        hint_text_color_normal: "white"
        hint_text_color_focus: "white"
        text_color_focus: "#ffffff"
        text_color_normal: "#ffffff"
        font_size: "20sp"
    MDTextField:
        id: password
        line_color_normal: "#ffffff"
        line_color_focus: "#ffffff"
        text_color: "#ffffff"
        hint_text: "Senha"
        size_hint_x: .8
        pos_hint: {"center_x": 0.5, "center_y": 0.57}
        mode: "rectangle"
        hint_text_color_normal: "white"
        hint_text_color_focus: "white"
        text_color_focus: "#ffffff"
        text_color_normal: "#ffffff"
        font_size: "20sp"
    MDTextField:
        id: quantity
        color_mode: "primary"
        line_color_normal: "#ffffff"
        line_color_focus: "#ffffff"
        hint_text: "Quantidade de comentários"
        size_hint_x: .8
        pos_hint: {"center_x": 0.5, "center_y": 0.39}
        mode: "rectangle"
        hint_text_color_normal: "white"
        hint_text_color_focus: "white"
        text_color_focus: "#ffffff"
        text_color_normal: "#ffffff"
        font_size: "20sp"
    MDRaisedButton:
        text: "Iniciar"
        theme_text_color: "Custom"
        text_color: "#FFFFFF"
        font_style: "Button"
        md_bg_color: "#C8439C"
        size_hint: .5, .13
        pos_hint: {"center_x": .5, "center_y": .155}
        font_size: "16sp"
        on_release: app.get_texts()

修改完成后，点击按钮即可正确调用get_texts方法，获取输入框内容。

内容的提问来源于stack exchange，提问作者Kauã Guilherme da Silva Leal