PyQt5 keyPressEvent 不适用于终止 App Qt Designer

Posted 2023-03-30

【中文标题】PyQt5 keyPressEvent 不适用于终止 App Qt Designer

【英文标题】：PyQt 5 keyPressEvent doesn`t work for terminating App Qt Designer

【发布时间】：2017-02-14 22:07:05

【问题描述】：

大家晚上好！ 我刚开始在 Python 中使用 pyQt5 和 Qt Designer，所以在编写下面的示例时遇到了一些麻烦。不管 App 内部的按钮等，问题都是关于使用 keyPressEvent 即通过 Esc 按钮终止 App。 有 2 个文件：一个由设计师生成，第二个 - keyPressEvent 所在的位置。 表单正在打开，但按 Esc 按钮没有任何反应。 期待您的帮助！ 谢谢。

ui_main.py

from PyQt5 import QtCore, QtWidgets
from PyQt5 import QtQuickWidgets

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(400, 300)
        self.gridLayout = QtWidgets.QGridLayout(MainWindow)
        self.gridLayout.setObjectName("gridLayout")
        self.bigWindow = QtQuickWidgets.QQuickWidget(MainWindow)
        self.bigWindow.setResizeMode(QtQuickWidgets.QQuickWidget.SizeRootObjectToView)
        self.bigWindow.setObjectName("bigWindow")
        self.gridLayout.addWidget(self.bigWindow, 0, 0, 1, 1)
        self.dateTimeEdit = QtWidgets.QDateTimeEdit(MainWindow)
        self.dateTimeEdit.setObjectName("dateTimeEdit")
        self.gridLayout.addWidget(self.dateTimeEdit, 1, 0, 1, 1)
        self.progressBar = QtWidgets.QProgressBar(MainWindow)
        self.progressBar.setProperty("value", 24)
        self.progressBar.setObjectName("progressBar")
        self.gridLayout.addWidget(self.progressBar, 2, 0, 1, 1)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "Dialog"))

if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QDialog()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

py_main.py

import sys
from PyQt5.QtWidgets import QDialog, QApplication
from PyQt5.QtCore import Qt
from ui_main import Ui_MainWindow


class MyMainWindow(QDialog, Ui_MainWindow):
    def __init__(self, parent=None):
        super(MyMainWindow, self).__init__(parent)
        self.show()
        self.setupUi(self)


    def keyPressEvent(self, event):
            if event.key() == Qt.Key_Escape:
                self.close()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    win = MyMainWindow()
    sys.exit(app.exec_())

【参考方案1】：

您必须在构造函数中使用eventFilter 方法：

qApp.installEventFilter(self)

然后我们重写方法：

def eventFilter(self, obj, event):
    if event.type() == QEvent.KeyPress:
        if event.key() == Qt.Key_Escape:
            self.close()
    return super(MyMainWindow, self).eventFilter(obj, event)

完整代码：

import sys
from PyQt5.QtWidgets import QDialog, QApplication, qApp
from PyQt5.QtCore import Qt, QEvent
from ui_main import Ui_MainWindow

class MyMainWindow(QDialog, Ui_MainWindow):
    def __init__(self, parent=None):
        super(MyMainWindow, self).__init__(parent)
        qApp.installEventFilter(self)
        self.setupUi(self)
        self.show()

    def eventFilter(self, obj, event):
        if event.type() == QEvent.KeyPress:
            if event.key() == Qt.Key_Escape:
                self.close()
        return super(MyMainWindow, self).eventFilter(obj, event)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    win = MyMainWindow()
    sys.exit(app.exec_())