如何从QListWidget获取当前选定的项目，而不是它记得的内容

Question

QListWidget returns on .selectedItems() even if there are no items currently selected (it remembers last item clicked or selected. So even if all its items were deselected it still returns what it remembers). But I need QListWidget to return ONLY that item that is currently selected.

.hasFocus() trick is not reliable since all the items could get hidden, QListWidget would be in focus. But it still will go ahead and return an item while nothing is selected.

Answer 1

I'm not sure why you don't think that .selectedItems() doesn't work. I just tried this with the code below and it's working correctly.

import sys

from PySide import QtGui


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

        self.resize(720, 480)
        central_widget = QtGui.QWidget(self)
        self.setCentralWidget(central_widget)

        layout = QtGui.QHBoxLayout(central_widget)

        self.text_edit = QtGui.QTextEdit(central_widget)
        layout.addWidget(self.text_edit)

        self.drop_list = QtGui.QListWidget(central_widget)
        self.drop_list.setSelectionMode(QtGui.QAbstractItemView.MultiSelection)
        self.drop_list.addItems(['one', 'two', 'three', 'four'])
        self.drop_list.itemSelectionChanged.connect(self.show_List)
        layout.addWidget(self.drop_list)

        statusbar = QtGui.QStatusBar(self)
        self.setStatusBar(statusbar)

        action_ShowList = QtGui.QAction(self)
        action_ShowList.triggered.connect(self.show_List)

        self.show()

    def show_List(self):
        self.text_edit.setText(repr(self.drop_list.selectedItems()))


if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    frame = MainWindow()
    sys.exit(app.exec_())

Everything selected:

Nothing selected:

Answer 2

I ended up using this approach:

def getSelectedItem(self):
    if not self.myTreeWidget.hasFocus(): return
    for selectedItem in self.myTreeWidget.selectedItems():
        if not selectedItem: continue
        if selectedItem.isHidden(): continue 
        return selectedItem

Edited later:

Here is his code (edited) showing the problem I've mentioned.

First select an item, then hide all the items by hitting 'Hide-Unhide' button. Click anywhere inside of now being empty listView (just to make sure everything is deselected). Click "Print Selected" button. Here is the image of the result:

from PyQt4 import QtCore, QtGui

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

        self.resize(720, 480)
        central_widget = QtGui.QWidget(self)
        self.setCentralWidget(central_widget)

        layout = QtGui.QHBoxLayout(central_widget)

        self.text_edit = QtGui.QTextEdit(central_widget)
        layout.addWidget(self.text_edit)

        self.drop_list = QtGui.QListWidget(central_widget)

        self.drop_list.setSelectionMode(QtGui.QAbstractItemView.MultiSelection)
        self.drop_list.addItems(['one', 'two', 'three', 'four'])
        layout.addWidget(self.drop_list)
        self.show()

        self.button1=QtGui.QPushButton("Hide-Unhide Items")
        self.button1.clicked.connect(self.hideUnhideItems)
        layout.addWidget(self.button1)

        self.button2=QtGui.QPushButton("Print Selected")
        self.button2.clicked.connect(self.getSelected)
        layout.addWidget(self.button2)

    def getSelected(self):
        self.text_edit.clear()
        self.text_edit.setText(repr(self.drop_list.selectedItems()))

    def hideUnhideItems(self):
        for i in range(self.drop_list.count()):
            item=self.drop_list.item(i)
            if not item.isHidden():
                item.setHidden(True)
            else:
                item.setHidden(False)

if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    frame = MainWindow()
    sys.exit(app.exec_())