该插槽不适用于 QListWidget itemClicked (pyqt)

Question

我创建了一个 QListWidget，我想将 itemClicked 与我的插槽连接起来。下面的代码就OK了：当我点击item时，listwidgetclicked已经被调用了

from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import sys


class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)

        self.imagelabel = QLabel()
        layout = QVBoxLayout()
        self.imagelabel.setLayout(layout)
        self.setCentralWidget(self.imagelabel)

        label1 = QLabel('hello, world')
        layout.addWidget(label1)

        newlistWidget = QListWidget()
        newlistWidget.addItem(QListWidgetItem('item3'))
        newlistWidget.addItem(QListWidgetItem('item4'))
        layout.addWidget(newlistWidget)
        newlistWidget.itemClicked.connect(self.listwidgetclicked)

    def listwidgetclicked(self):
        print('click')

app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec_()

但是，我想把 GUI 的所有代码放在一起。所以我创建了一个类，并将这个类中的信号和槽连接起来。当我单击该项目时，listwidgetclicked 不起作用，代码是：

from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import sys

class GUI(QObject):
    def __init__(self):
        super(GUI, self).__init__()
        self.layout = QVBoxLayout()
        self.initGUI()

    def getLayout(self):
        return self.layout

    def initGUI(self):
        self.listWidget = QListWidget()
        self.listWidget.addItem(QListWidgetItem('item1'))
        self.listWidget.addItem(QListWidgetItem('item2'))
        self.listWidget.itemClicked.connect(self.listwidgetclicked)
        self.layout.addWidget(self.listWidget)

    def listwidgetclicked(self, item):
        print('click')

class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)

        self.imagelabel = QLabel()
        layout = QVBoxLayout()
        self.imagelabel.setLayout(layout)
        self.setCentralWidget(self.imagelabel)

        label1 = QLabel('hello, world')
        layout.addWidget(label1)
        listWidget = GUI()
        layout.addLayout(listWidget.getLayout())

app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec_()

我不知道这两个代码有什么区别。

Answer 1

试试看：

import sys
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *

class GUI(QListWidget):
    def __init__(self):
        super(GUI, self).__init__()
        self.layout = QVBoxLayout()
        self.initGUI()

#    def getLayout(self):
#        return self.layout

    def initGUI(self):
#        self.listWidget = QListWidget()
        self.addItem(QListWidgetItem('item1'))
        self.addItem(QListWidgetItem('item2'))
        self.itemClicked.connect(self.listwidgetclicked)
        self.layout.addWidget(self)       #.listWidget)

    def listwidgetclicked(self, item):
        print('!!! click {}'.format(item.text()))

class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)

        self.imagelabel = QLabel()
        layout = QVBoxLayout()
        self.imagelabel.setLayout(layout)
        self.setCentralWidget(self.imagelabel)

        label1 = QLabel('hello, world')
        layout.addWidget(label1)
        listWidget = GUI()
#        layout.addLayout(listWidget.getLayout())  # ---
        layout.addWidget(listWidget)               # +++

app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec_()

更新：

from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import sys

class GUI(QObject):
    def __init__(self):
        super(GUI, self).__init__()
        self.layout = QVBoxLayout()
        self.initGUI()

    def getLayout(self):
        return self.layout

    def initGUI(self):
        self.listWidget = QListWidget()
        self.listWidget.addItem(QListWidgetItem('item1'))
        self.listWidget.addItem(QListWidgetItem('item2'))
        self.listWidget.itemClicked.connect(self.listwidgetclicked)
        self.layout.addWidget(self.listWidget)

    def listwidgetclicked(self, item):
        print('click -> {}'.format(item.text()))

class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)

        self.imagelabel = QLabel()
        layout = QVBoxLayout()
        self.imagelabel.setLayout(layout)
        self.setCentralWidget(self.imagelabel)

        label1 = QLabel('hello, world')
        layout.addWidget(label1)


        self.listWidget = GUI()                        # <--- + self.
        layout.addLayout(self.listWidget.getLayout())  # <--- + self.


app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec_()