带Qlabel和signal&s的Qcombobox

2024-03-29 06:35:46 发布

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我有一个Qgroupbox,它包含Qcombobox和Qlabel,我想从Qcombobox中选择一个值并将其显示为Qlabel。我有完整的代码,即使我在函数中打印前后值,一切都正常工作,只显示setText不会将文本设置为Qlabel并更新它。在

当前屏幕

enter image description here

我想要什么

enter image description here

我已经更正了信号代码,当其中的Qgroupbox出现或值发生变化时,self.activation.connect(......)将发出索引的int。为了确保可以工作,我在def setdatastrength(self, index)内打印it-value,见下图,它确实工作,然后参数将传递给函数self.concreteproperty.display_condata(it),并在def display_condata(self, value)内打印值,以确保值传递,如下图所示,它确实有效。此行代码self.con_strength_value.setText(fmt.format(L_Display)) 不会给Qlabel赋值。在

enter image description here

剧本

import sys
from PyQt5 import QtCore, QtGui, QtWidgets

class secondtabmaterial(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(secondtabmaterial, self).__init__(parent)

        self.concretewidgetinfo = ConcreteStrengthInFo()

        Concrete_Group = QtWidgets.QGroupBox(self)
        Concrete_Group.setTitle("&Concrete")
        Concrete_Group.setLayout(self.concretewidgetinfo.grid)


class ConcreteStrengthComboBox(QtWidgets.QComboBox):
    def __init__(self, parent = None):
        super(ConcreteStrengthComboBox, self).__init__(parent)


        self.addItems(["C12/15","C16/20","C20/25","C25/30","C30/37","C35/45"
                     ,"C40/50","C45/55","C50/60","C55/67","C60/75","C70/85",
                                                        "C80/95","C90/105"])

        self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))

        self.compressive_strength = ["12","16","20","25","30","35","40",
                                      "45","50","55","60","70","80","90"]


class ConcreteProperty(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(ConcreteProperty, self).__init__(parent)
        self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))


        concretestrength_lay = QtWidgets.QHBoxLayout(self)
        fctd = "\nfcd\n\nfctd\n\nEc"
        con_strength = QtWidgets.QLabel(fctd)
        self.con_strength_value = QtWidgets.QLabel(" ")
        concretestrength_lay.addWidget(con_strength)
        concretestrength_lay.addWidget(self.con_strength_value, alignment=QtCore.Qt.AlignRight)
        self.setLayout(concretestrength_lay)

    @QtCore.pyqtSlot(int)
    def display_condata(self, value):
        try:
            L_Display = str(value)
            print("-------- After ------")
            print(L_Display, type(L_Display))

            fmt = "{}mm"
            self.con_strength_value.setText(fmt.format(L_Display))

       except ValueError:
           print("Error")

class ConcreteStrengthInFo(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(ConcreteStrengthInFo, self).__init__(parent)

        self.concreteproperty = ConcreteProperty()
        self.concretestrengthbox = ConcreteStrengthComboBox()

        self.concretestrengthbox.activated.connect(self.setdatastrength)

        hbox = QtWidgets.QHBoxLayout()
        concrete_strength = QtWidgets.QLabel("Concrete strength: ")
        hbox.addWidget(concrete_strength)
        hbox.addWidget(self.concretestrengthbox)

        self.grid = QtWidgets.QGridLayout()
        self.grid.addLayout(hbox, 0, 0)
        self.grid.addWidget(self.concreteproperty, 1, 0)

    @QtCore.pyqtSlot(int)
    def setdatastrength(self, index):
        it = self.concretestrengthbox.compressive_strength[index]
        self.concreteproperty.display_condata(it)

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

以上代码是正确的和最终的。现在它正常工作了。在

enter image description here


Tags: 代码selfinitvaluedefdisplayitcon
2条回答

我认为问题是你的接收槽与任何可用的.activated信号都不匹配。在

self.activated.connect(self.setdatastrength)

@QtCore.pyqtSlot()
def setdatastrength(self):
    index = self.currentIndex()
    it = self.compressive_strength[index]
    print(it)
    self.concreteproperty.display_condata(it)    

QComboBox.activated信号发出索引的int,或所选值的strSee documentation。在

您已经将它附加到setdatastrength,它接受不接受任何参数(除了来自对象的self),这意味着它与任何可用信号的签名都不匹配,并且不会被调用。如果您更新定义以添加索引值,并接受单个int它应该可以工作。在

^{pr2}$

在更新之后-上面的问题看起来已经修复了,虽然您不需要在setdatastrength中添加index = self.currentIndex(),但它不会造成任何伤害。在

看看你的代码,我认为标签正在更新。问题是你根本看不到标签。正在查看ConcreteProperty的初始化

class ConcreteProperty(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(ConcreteProperty, self).__init__(parent)
        self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))


        self.concretestrength_lay = QtWidgets.QHBoxLayout()
        fctd = "\nfcd\n\nfctd\n\nEc"
        con_strength = QtWidgets.QLabel(fctd)
        self.con_strength_value = QtWidgets.QLabel(" ")
        self.concretestrength_lay.addWidget(con_strength)
        self.concretestrength_lay.addWidget(self.con_strength_value, alignment=QtCore.Qt.AlignLeft)

更改没有出现的原因是您创建了两个对象,一个在ConcreteStrengthInfo中,一个在ConcreteStrengthComboBox中。对组合框的更新会触发附加到组合框的ConcreteProperty的更新,而不是另一个(它们是单独的对象)。可见的ConcreteProperty不受影响。在

要实现这一点,您需要将signal attachment+slot移出组合框对象。以下是这两部分的替代品-

class ConcreteStrengthComboBox(QtWidgets.QComboBox):
    def __init__(self, parent = None):
        super(ConcreteStrengthComboBox, self).__init__(parent)

        self.addItems(["C12/15","C16/20","C20/25","C25/30","C30/37","C35/45","C40/50","C45/55",
                       "C50/60","C55/67","C60/75","C70/85","C80/95","C90/105"])

        self.setFont(QtGui.QFont("Helvetica", 10, QtGui.QFont.Normal, italic=False))

        self.compressive_strength = ["12","16","20","25","30","35","40","45","50","55",
                                     "60","70","80","90"]




class ConcreteStrengthInFo(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(ConcreteStrengthInFo, self).__init__(parent)

        hbox = QtWidgets.QHBoxLayout()
        concrete_strength = QtWidgets.QLabel("Concrete strength: ")
        hbox.addWidget(concrete_strength)

        self.concreteproperty = ConcreteProperty()
        self.concretestrengthbox = ConcreteStrengthComboBox()
        hbox.addWidget(self.concretestrengthbox)


        self.concretestrengthbox.activated.connect(self.setdatastrength)

        self.vlay = QtWidgets.QVBoxLayout()
        self.vlay.addLayout(hbox)
        self.vlay.addLayout(self.concreteproperty.concretestrength_lay)


    @QtCore.pyqtSlot(int)
    def setdatastrength(self, index):
        it = self.concretestrengthbox.compressive_strength[index]
        print(it)
        self.concreteproperty.display_condata(it)

这对我在当地很管用。在

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