Distinguishing Single and Double Clicks on QListWidget in PyQt4

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The problem

QListWidget exposes itemClicked and itemDoubleClicked, but triggering the double-click signal also fires the single-click slot. That is fine when the actions are unrelated, but not when the logic overlaps.

Solution

Qt does not provide a built-in fix, so we debounce the signals ourselves. A Stack Overflow answer suggests this C++ pattern:

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void YourClass::itemClicked(QListWidgetItem* listWidgetItem) {
    if (!mDoubleClicked) {
        QTimer::singleShot(300, this, SLOT(itemClickedTimeout()));
        mSingleClickedItem = listWidgetItem;
    }
}

void YourClass::itemClickedTimeout() {
    if (!mDoubleClicked) {
        // do something, listitem has been clicked once
    } else mDoubleClicked = false;
}

void YourClass::itemDoubleClicked(QListWidgetItem* listWidgetItem) {
    mDoubleClicked = true;

    // do something, listitem has been clicked twice
}

Translated into PyQt:

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class Main(QtGui.QMainWindow):
    
    def __init__():
        
        self.is_double_clicked = False
        self.listwidget.itemClicked.connect(self.item_clicked)
        self.listwidget.itemDoubleClicked.connect(self.item_double_clicked)
    
    .....................................
    
    def item_clicked(self, item):
        if not self.is_double_clicked:
            QtCore.QTimer.singleShot(300, self.item_clicked_timeout)

    def item_clicked_timeout(self):
        if not self.is_double_clicked:
            # do something when item clicked
            pass
        else:
            self.is_double_clicked = False
            
    def item_double_clicked(self):
        self.is_double_clicked = True
        # do something when item double clicked
        pass

Reference:

《QListWidget itemClicked and itemDoubleClicked - block single click if double click》