Question

I need to process some data AFTER a drop event has occured on a widget.

i.e a user selects some items in list A and drops them in list B. My program needs to compare the 2 lists after B has added the items selected from A.

Any ideas?

Answer 1

Here’s a PyQt script that demonstrates two ways to trap drop events:

from PyQt4 import QtGui, QtCore

class Window(QtGui.QMainWindow):
    def __init__(self):
        QtGui.QMainWindow.__init__(self)
        widget = QtGui.QWidget(self)
        self.setCentralWidget(widget)
        layout = QtGui.QVBoxLayout(widget)
        self.listA = ListWidget(self)
        self.listB = QtGui.QListWidget(self)
        self.listB.viewport().installEventFilter(self)
        for widget in (self.listA, self.listB):
            widget.setAcceptDrops(True)
            widget.setDragEnabled(True)
            for item in 'One Two Three Four Five Six'.split():
                widget.addItem(item)
            layout.addWidget(widget)

    def eventFilter(self, source, event):
        if (event.type() == QtCore.QEvent.Drop and
            source is self.listB.viewport()):
            self.listB.dropEvent(event)
            if event.isAccepted():
                print 'eventFilter', self.listB.count()
            return True
        return QtGui.QMainWindow.eventFilter(self, source, event)

class ListWidget(QtGui.QListWidget):
    def __init__(self, parent):
        QtGui.QListWidget.__init__(self, parent)

    def dropEvent(self, event):
        QtGui.QListWidget.dropEvent(self, event)
        if event.isAccepted():
            print 'dropEvent', self.count()

if __name__ == '__main__':

    import sys
    app = QtGui.QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())