选择 QCompleter 项目后无法清除 QLineEdit

Fail to clear QLineEdit after selecting QCompleter item

从 QCompleter 中选择项目后,我在从 QLineEdit 中清除文本时遇到问题。我想打印QCompleter中选中的item的文字,然后立即清空QLineEdit,我只打印成功了,但之后无法清空QLineEdit的文字。

这是我的代码:

import sys
from PyQt4 import QtGui, QtCore

auto_completer_words = ["chair"]


def get_data(model):
    model.setStringList(auto_completer_words)


class MainWindow(QtGui.QMainWindow):
    def __init__(self):
        super(self.__class__, self).__init__()
        self.resize(300, 300)

        self.line_edit = QtGui.QLineEdit(self)
        self.line_edit.setGeometry(QtCore.QRect(100, 100, 100, 30))

        self.completer = QtGui.QCompleter()
        self.line_edit.setCompleter(self.completer)

        model = QtGui.QStringListModel()
        self.completer.setModel(model)
        get_data(model)

        self.completer.activated.connect(self.get_data_in_le)


def get_data_in_le(self):
    print(self.line_edit.text())
    self.line_edit.clear()


def main():
    app = QtGui.QApplication(sys.argv)
    w = MainWindow()
    w.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()

问题是激活的 QCompleter 信号在分配一个值之前被触发,所以最后 clear() 工作但在 QLineEdit 为空时清除它。解决方法是稍后清理一下QTimer可以使用:

def get_data_in_le(self):
    print(self.line_edit.text())
    QtCore.QTimer.singleShot(0, self.line_edit.clear)

更好的解决方案是:

self.connect(self.completer, QtCore.SIGNAL("activated(const QString&)"), self.line_edit.clear, QtCore.Qt.QueuedConnection)