在没有文本输入的情况下立即在 QStyledItemDelegate 中弹出 QCompleter

Question

我在 QTableWidget 列上有一个 QCompleter。一旦用户开始编辑，我希望完成者弹出，而不是等待他们先输入文本。我将 QStyledItemDelegate 的 setEditorData 函数子类化来执行此操作，这对我来说似乎最有意义，但是当我调用 completer.complete() 时，直到我完成编辑（此时弹出窗口）才会发生任何事情。

这是我的委托代码：

class CompleterItemDelegate(QtGui.QStyledItemDelegate):
    def createEditor(self, parent, option, index):
        completer = QtGui.QCompleter(['test', 'test2'])
        completer.setCompletionMode(completer.UnfilteredPopupCompletion)

        edit = QtGui.QLineEdit(parent)
        edit.setCompleter(completer)
        return edit

    def setEditorData(self, editor, index):
        completer = editor.completer()
        completer.complete() # does not fire until after editing is done
        completer.popup().show() # no luck here either
        print("setting editor data") # this however does work as expected...
        super().setEditorData(editor, index)

Answer 1

您必须在显示小部件时调用complete()，为此您可以使用showEvent() 方法：

from PyQt4 import QtCore, QtGui


class LineEdit(QtGui.QLineEdit):
    def showEvent(self, event):
        if self.completer() is not None:
            QtCore.QTimer.singleShot(0, self.completer().complete)
        super().showEvent(event)


class CompleterItemDelegate(QtGui.QStyledItemDelegate):
    def createEditor(self, parent, option, index):
        completer = QtGui.QCompleter(["test", "test2"])
        completer.setCompletionMode(QtGui.QCompleter.UnfilteredPopupCompletion)
        edit = LineEdit(parent)
        edit.setCompleter(completer)
        return edit


def main(args):
    app = QtGui.QApplication(args)

    w = QtGui.QTableWidget(4, 4)
    delegate = CompleterItemDelegate(w)
    w.setItemDelegate(delegate)
    w.show()

    ret = app.exec_()
    return ret


if __name__ == "__main__":
    import sys

    sys.exit(main(sys.argv))