"使用QSettings恢复QCheckBox"

Question

拥有QCheckBox想要在关闭文件后保存并还原checkstate。你知道吗

尝试了以下，但它没有真正的工作！你知道吗

代码：

import sys
from PyQt5 import QtCore, QtGui, QtWidgets

class SecondOrder(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(SecondOrder, self).__init__(parent)
        self.setFont(QtGui.QFont("Helvetica", 8, QtGui.QFont.Normal, italic=False))

        curvaturelabel = QtWidgets.QLabel('Nominal curvature')
        stiffnesslabel = QtWidgets.QLabel('Nominal stiffness')
        simcurvaturelabel = QtWidgets.QLabel('Simplified nominal curvature')   

        self.curvaturecheck = QtWidgets.QCheckBox()
        self.stiffnesscheck = QtWidgets.QCheckBox()
        self.simcurvaturecheck = QtWidgets.QCheckBox()

        self.clay = QtWidgets.QVBoxLayout()
        self.clay.addWidget(curvaturelabel)
        self.clay.addWidget(stiffnesslabel)
        self.clay.addWidget(simcurvaturelabel)

        self.dlay = QtWidgets.QVBoxLayout()
        self.dlay.addWidget(self.curvaturecheck)
        self.dlay.addWidget(self.stiffnesscheck)
        self.dlay.addWidget(self.simcurvaturecheck)

        grid = QtWidgets.QGridLayout(self)
        grid.addLayout(self.dlay, 0, 0)
        grid.addLayout(self.clay, 0, 1)

        Secondorder_Group = QtWidgets.QGroupBox(self)
        Secondorder_Group.setTitle("&Second order analysis method")
        Secondorder_Group.setLayout(grid)

        self.elay = QtWidgets.QHBoxLayout(self)
        self.elay.addWidget(Secondorder_Group)     
        self.elay.setSizeConstraint(self.elay.SetFixedSize)

        group = QtWidgets.QButtonGroup(self) 
        group.addButton(self.curvaturecheck) 
        group.addButton(self.stiffnesscheck) 
        group.addButton(self.simcurvaturecheck)

        self.readSettings()

        self.curvaturecheck.stateChanged.connect(lambda: self.writeSettings())
        self.stiffnesscheck.stateChanged.connect(lambda: self.writeSettings())
        self.simcurvaturecheck.stateChanged.connect(lambda: self.writeSettings())

    def readSettings(self):
        settings = QtCore.QSettings('file.ini')
        settings.beginGroup("QCheckBox")
        self.curvaturecheck.setCheckState(settings.value("A", QtCore.Qt.Checked, bool))
        self.stiffnesscheck.setCheckState(settings.value("B", False, bool))
        self.simcurvaturecheck.setCheckState(settings.value("C", False, bool))
        settings.endGroup()

    def writeSettings(self):
        settings = QtCore.QSettings('file.ini')
        settings.beginGroup("QCheckBox")
        settings.setValue("A", self.curvaturecheck.isCheckable())
        settings.setValue("B", self.stiffnesscheck.isCheckable())
        settings.setValue("C", self.simcurvaturecheck.isCheckable())
        settings.endGroup()


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = SecondOrder()
    w.show()
    sys.exit(app.exec_())

请注意，下面的代码是尝试，它确实保存和恢复，但它混合了多个检查？希望能够检查一次并恢复。你知道吗

    settings.setValue("A", self.curvaturecheck.isChecked())
    settings.setValue("B", self.stiffnesscheck.isChecked())
    settings.setValue("C", self.simcurvaturecheck.isChecked())

Answer 1

如果要保存T类型的数据，则必须使用使用T类型的函数，在本例中，使用isChecked（）保存布尔值，并希望使用使用Qt:：CheckState类型的函数setCheckState（），从而导致错误。你知道吗

考虑到上述情况，有两种解决方案：

• 使用bool：

def readSettings(self):
    settings = QtCore.QSettings("file.ini")
    settings.beginGroup("QCheckBox")
    self.curvaturecheck.setChecked(settings.value("A", True, bool))
    self.stiffnesscheck.setChecked(settings.value("B", False, bool))
    self.simcurvaturecheck.setChecked(settings.value("C", False, bool))
    settings.endGroup()

def writeSettings(self):
    settings = QtCore.QSettings("file.ini")
    settings.beginGroup("QCheckBox")
    settings.setValue("A", self.curvaturecheck.isChecked())
    settings.setValue("B", self.stiffnesscheck.isChecked())
    settings.setValue("C", self.simcurvaturecheck.isChecked())
    settings.endGroup()

• 使用Qt:：CheckState

def readSettings(self):
    settings = QtCore.QSettings("file.ini")
    settings.beginGroup("QCheckBox")
    self.curvaturecheck.setCheckState(
        settings.value("A", QtCore.Qt.Checked, QtCore.Qt.CheckState)
    )
    self.stiffnesscheck.setCheckState(
        settings.value("B", QtCore.Qt.Unchecked, QtCore.Qt.CheckState)
    )
    self.simcurvaturecheck.setCheckState(
        settings.value("C", QtCore.Qt.Unchecked, QtCore.Qt.CheckState)
    )
    settings.endGroup()

def writeSettings(self):
    settings = QtCore.QSettings("file.ini")
    settings.beginGroup("QCheckBox")
    settings.setValue("A", self.curvaturecheck.checkState())
    settings.setValue("B", self.stiffnesscheck.checkState())
    settings.setValue("C", self.simcurvaturecheck.checkState())
    settings.endGroup()

建议您删除位于settings.fileName()中的.ini文件。你知道吗

另一方面，无需使用lambda函数，请将代码更改为：

self.curvaturecheck.stateChanged.connect(self.writeSettings)
self.stiffnesscheck.stateChanged.connect(self.writeSettings)
self.simcurvaturecheck.stateChanged.connect(self.writeSettings)

Answer 2

https://doc.qt.io/qt-5/qbuttongroup.html#details

QButtonGroup provides an abstract container into which button widgets can be placed.. It does not provide a visual representation of this container (see QGroupBox for a container widget), but instead manages the states of each of the buttons in the group.

setValue()在每个复选框上可以切换另一个复选框。你知道吗

但真正的问题是isCheckable()（方法可以检查或不检查）。可能需要使用isChecked()（值设置为true）。你知道吗

编辑。您可以尝试通过setChecked()设置状态。你知道吗

或者如果您想支持部分选中的，使用setCheckState()（如您所用）和checkState()来获取信息。你知道吗