如何获取具有焦点的小部件

Posted 2023-03-30

【中文标题】如何获取具有焦点的小部件

【英文标题】：How to get the widget that has the focus

【发布时间】：2019-05-09 19:00:43

【问题描述】：

如标题所示，我需要获取孩子的姓名。但是，模板来自 Qt Creator，所有对象都是在程序中创建的。我不知道如何对它们进行子类化（因为我不应该更改生成的文件），所以调用后的所有对象都将返回self.sender()。有没有其他办法？

编辑：

我正在提供 mre 代码来重现该问题。这是生成的文件：

from PyQt5 import QtCore, QtGui, QtWidgets

class UiBazaDanych(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(400, 300)
        self.centralWidget = QtWidgets.QWidget(MainWindow)
        self.centralWidget.setObjectName("centralWidget")
        self.gridLayout = QtWidgets.QGridLayout(self.centralWidget)
        self.gridLayout.setContentsMargins(11, 11, 11, 11)
        self.gridLayout.setSpacing(6)
        self.gridLayout.setObjectName("gridLayout")
        self.comboBox = QtWidgets.QComboBox(self.centralWidget)
        self.comboBox.setObjectName("comboBox")
        self.comboBox.addItem("")
        self.comboBox.addItem("")
        self.comboBox.addItem("")
        self.gridLayout.addWidget(self.comboBox, 0, 2, 1, 1)
        self.lineEdit = QtWidgets.QLineEdit(self.centralWidget)
        self.lineEdit.setObjectName("lineEdit")
        self.gridLayout.addWidget(self.lineEdit, 1, 0, 1, 1)
        self.dateEdit = QtWidgets.QDateEdit(self.centralWidget)
        self.dateEdit.setObjectName("dateEdit")
        self.gridLayout.addWidget(self.dateEdit, 1, 2, 1, 1)
        self.label_2 = QtWidgets.QLabel(self.centralWidget)
        self.label_2.setObjectName("label_2")
        self.gridLayout.addWidget(self.label_2, 1, 1, 1, 1)
        self.label = QtWidgets.QLabel(self.centralWidget)
        self.label.setObjectName("label")
        self.gridLayout.addWidget(self.label, 0, 0, 1, 1)
        self.pushButton = QtWidgets.QPushButton(self.centralWidget)
        self.pushButton.setObjectName("pushButton")
        self.gridLayout.addWidget(self.pushButton, 2, 2, 1, 1)
        self.doubleSpinBox = QtWidgets.QDoubleSpinBox(self.centralWidget)
        self.doubleSpinBox.setButtonSymbols(QtWidgets.QAbstractSpinBox.NoButtons)
        self.doubleSpinBox.setObjectName("doubleSpinBox")
        self.gridLayout.addWidget(self.doubleSpinBox, 2, 0, 1, 1)
        MainWindow.setCentralWidget(self.centralWidget)
        self.menuBar = QtWidgets.QMenuBar(MainWindow)
        self.menuBar.setGeometry(QtCore.QRect(0, 0, 400, 21))
        self.menuBar.setObjectName("menuBar")
        MainWindow.setMenuBar(self.menuBar)
        self.mainToolBar = QtWidgets.QToolBar(MainWindow)
        self.mainToolBar.setObjectName("mainToolBar")
        MainWindow.addToolBar(QtCore.Qt.TopToolBarArea, self.mainToolBar)
        self.statusBar = QtWidgets.QStatusBar(MainWindow)
        self.statusBar.setObjectName("statusBar")
        MainWindow.setStatusBar(self.statusBar)

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

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.comboBox.setItemText(0, _translate("MainWindow", "Agnieszka"))
        self.comboBox.setItemText(1, _translate("MainWindow", "Monika"))
        self.comboBox.setItemText(2, _translate("MainWindow", "Zenek"))
        self.label_2.setText(_translate("MainWindow", "zl"))
        self.label.setText(_translate("MainWindow", "Kasjer"))
        self.pushButton.setText(_translate("MainWindow", "WYŚLIJ"))

还有我的代码：

from PyQt5 import QtWidgets, QtCore, QtGui, QtPrintSupport
from Ui_Baza_Danych import UiBazaDanych

class InputWindow(QtWidgets.QMainWindow, UiBazaDanych):
    def __init__(self):
        super().__init__()
        self.setupUi(self)
        self.show()
        QtWidgets.QShortcut(QtCore.Qt.Key_PageDown, self, self.pagedown)
    def pagedown(self):
        self.focusNextPrevChild(True)
        # here should be a method to return selected child's name

import sys
from PyQt5.QtWidgets import QApplication


app = QApplication(sys.argv)
show_all = InputWindow()
sys.exit(app.exec_())

【参考方案1】：

如果你想得到有焦点的widget你必须使用QApplication的focusWidget方法：

def pagedown(self):
    self.focusNextPrevChild(True)
    widget = QtWidgets.QApplication.focusWidget()
    print(widget)