PyQt6点击signinButton程序崩溃，退出码0xC0000409问题排查

问题原因分析 #

崩溃核心是代码中引用了未定义的控件属性，触发未捕获的AttributeError导致程序异常退出：

• UI类中通过findChild获取signinButton并赋值给self.button，但后续错误使用self.signinButton连接信号，该属性未定义
• Second类中同理，获取SubmitSignButton赋值给self.button，却用self.SubmitSignButton连接信号，属性未定义
• UI类初始化时调用self.show()，之后又将实例添加到QStackedWidget，导致窗口重复显示引发冲突

修复后的代码 #

from PyQt6.QtWidgets import (
    QMainWindow, QApplication, QDialog, QDialogButtonBox, QLabel, QTextEdit, QPushButton, QMessageBox, QMdiArea,
    QTableWidgetItem, QStackedWidget
)
from PyQt6 import uic
import sys


class UI(QMainWindow):
    def __init__(self):
        super(UI, self).__init__()
        uic.loadUi(r"C:\Users\csc\Documents\Rentour\front.ui", self)
        # 正确绑定按钮控件到对应属性
        self.signinButton = self.findChild(QPushButton, "signinButton")
        self.signinButton.clicked.connect(self.OpenSignUp)

    def OpenSignUp(self):
        sign_up = Second()
        widget.addWidget(sign_up)
        widget.setCurrentIndex(widget.currentIndex() + 1)

class Second(QMainWindow):
    def __init__(self):
        super(Second, self).__init__()
        uic.loadUi(r"C:\Users\csc\Documents\Rentour\signpopup.ui", self)
        # 正确绑定按钮控件到对应属性
        self.SubmitSignButton = self.findChild(QPushButton, "SubmitSignButton")
        self.SubmitSignButton.clicked.connect(self.SignUpSave)

    def SignUpSave(self):
        email = self.EmailLine.text()
        phoneno = self.PhonenoLine.text()
        name = self.NameLine.text()
        password = self.PasswordLine.text()
        print(password)

if __name__ == "__main__":
    app = QApplication(sys.argv)
    widget = QStackedWidget()
    mainwindow = UI()
    widget.addWidget(mainwindow)
    widget.show()
    sys.exit(app.exec())

额外优化建议 #

• 将widget作为参数传递给UI类，避免全局变量，提升代码封装性
• 确保Qt Designer中控件的objectName与代码引用名称完全一致（区分大小写）
• 可添加输入内容合法性校验（如邮箱格式、密码长度等）

内容的提问来源于stack exchange，提问作者Aaron Matthew gino