python - 使用 QDataWidgetMapper 立即更改模型

Question

我有一个 QTableView，它有一列带有 True/False 值。要更改此列中的值，我使用 QDataWidgetMapper 复选框。
我希望在单击复选框后立即更改值。通常在复选框失去焦点后进行更改(换句话说，您需要在应用程序的其他地方进行额外的点击)。
我试图这样做:checkBox.stateChanged.connect(lambda: data_mapper.submit())，但我不喜欢使用这种方法发出太多信号:首先它发出所有映射项都已更改的信号, 并且在复选框失去焦点后 - 仅更改一项的信号。
因此，我们的目标是在单击复选框后立即更新模型，并且只发出一个信号。
代码:

from PyQt5 import QtCore, QtGui, QtWidgets
import sys

class Mainwindow(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()

        self.table = QtWidgets.QTableView()
        self.widget_1 = Widget_1(self)

        self.layout_1 = QtWidgets.QHBoxLayout()
        self.layout_1.addWidget(self.table)
        self.layout_1.addWidget(self.widget_1)

        self.setLayout(self.layout_1)

        headers = ['State', 'Prorerty_1', 'Prorerty_2']
        data = [
        [True, '1', '2'],
        [False, '3', '4']
        ]

        self.model = ListModel(data, headers)
        self.table.setModel(self.model)
        self.table.setSelectionBehavior(self.table.SelectRows)

        self.table.clicked.connect(self.set_data_mapper)

        self.model.dataChanged.connect(lambda value: print(value.row(), value.column(), value.data()))

    def set_data_mapper(self):
        position = self.table.selectionModel().selectedIndexes()[0].row()

        self.widget_1.data_mapper.setModel(self.model)
        self.widget_1.data_mapper.addMapping(self.widget_1.checkBox, 0)
        self.widget_1.data_mapper.addMapping(self.widget_1.lineEdit, 1)
        self.widget_1.data_mapper.setCurrentIndex(position)

        self.widget_1.checkBox.stateChanged.connect(lambda: self.widget_1.data_mapper.submit())

class Widget_1(QtWidgets.QWidget):

    def __init__(self, parent):
        super().__init__()
        self.parent = parent

        self.layout_1 = QtWidgets.QGridLayout()
        self.state = QtWidgets.QLabel('State')
        self.checkBox = QtWidgets.QCheckBox()
        self.property = QtWidgets.QLabel('Prop.1')
        self.lineEdit = QtWidgets.QLineEdit()

        self.layout_1.addWidget(self.state, 0, 0)
        self.layout_1.addWidget(self.checkBox, 0, 1)
        self.layout_1.addWidget(self.property, 1, 0)
        self.layout_1.addWidget(self.lineEdit, 1, 1)

        self.setLayout(self.layout_1)

        self.data_mapper = QtWidgets.QDataWidgetMapper()

class ListModel(QtCore.QAbstractTableModel):

    def __init__(self, data_list = [[]], headers = [], parent = None):
        super(ListModel, self).__init__()
        self.data_list = data_list
        self.headers = headers

    def rowCount(self, parent):
        return len(self.data_list)

    def columnCount(self, parent):
        return len(self.headers)

    def data(self, index, role):
        if role == QtCore.Qt.DisplayRole:
            row = index.row()
            column = index.column()
            value = self.data_list[row][column]
            return value

        if role == QtCore.Qt.EditRole:
            row = index.row()
            column = index.column()
            value = self.data_list[row][column]
            return value

        if role == QtCore.Qt.FontRole:
            if index.column() == 0:
                boldfont = QtGui.QFont()
                boldfont.setBold(True)
                return boldfont

    def setData(self, index, value, role = QtCore.Qt.EditRole):
        if role == QtCore.Qt.EditRole:
            row = index.row()
            column = index.column()
            self.data_list[row][column] = value
            self.dataChanged.emit(index, index)
            return True
        return False

    def headerData(self, section, orientation, role):
        if role == QtCore.Qt.DisplayRole:
            if orientation == QtCore.Qt.Horizontal:
                return self.headers[section]

if __name__ == '__main__':
    app = QtWidgets.QApplication([])
    application = Mainwindow()
    application.show()


    sys.exit(app.exec())

Answer 1

默认情况下，QDataWidgetMapper 策略是“AutoSubmit”，它会在任何小部件失去焦点时更新模型，因此如果您希望它在失去焦点时不发出，则必须使用“ManualSubmit”策略。另一方面，连接必须只完成一次，因为如果你这样做 n 次，那么将发出 n 个信号，在你的情况下，“每次按下按钮时都会调用 set_data_mapper。

class Mainwindow(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()

        self.table = QtWidgets.QTableView(
            selectionBehavior=QtWidgets.QAbstractItemView.SelectRows
        )
        self.widget_1 = Widget_1(self)

        lay = QtWidgets.QHBoxLayout(self)
        lay.addWidget(self.table)
        lay.addWidget(self.widget_1)

        headers = ["State", "Prorerty_1", "Prorerty_2"]
        data = [[True, "1", "2"], [False, "3", "4"]]

        self.model = ListModel(data, headers)
        self.table.setModel(self.model)
        self.table.setSelectionBehavior(self.table.SelectRows)

        self.widget_1.data_mapper.setModel(self.model)
        self.widget_1.data_mapper.addMapping(self.widget_1.checkBox, 0)
        self.widget_1.data_mapper.addMapping(self.widget_1.lineEdit, 1)

        self.widget_1.data_mapper.setSubmitPolicy(
            QtWidgets.QDataWidgetMapper.ManualSubmit
        )

        self.widget_1.checkBox.stateChanged.connect(self.widget_1.data_mapper.submit)
        self.widget_1.lineEdit.textChanged.connect(self.widget_1.data_mapper.submit)

        self.table.clicked.connect(self.update_current_index)

        self.model.dataChanged.connect(
            lambda value: print(value.row(), value.column(), value.data())
        )

    def update_current_index(self, index):
        position = index.row()
        self.widget_1.data_mapper.setCurrentIndex(position)