PyQt, QComboBox with QStringModel cause QObject::startTimer: QTimer can only be used with threads started with QThread

Question

below is runnable example for PyQt4, I using below code and got very strange issue like this QObject::startTimer: QTimer can only be used with threads started with QThread after closed the window:

combo = ExtendedComboBox()
# combo.addItems(string_list)
combo.setModel(QStringListModel(string_list))

Once I changed to below codes, everything is working well:

combo = ExtendedComboBox()
combo.addItems(string_list)
# combo.setModel(QStringListModel(string_list))

Every your comment is appreciated :)

attach full codes here:

#!/usr/bin/env python
# -*- coding: utf-8 -*-
from PyQt4.QtCore import Qt
from PyQt4.QtGui import QCompleter, QComboBox, QSortFilterProxyModel, QDialog


class ExtendedComboBox(QComboBox):
    def __init__(self, parent=None):
        super(ExtendedComboBox, self).__init__(parent)

        self.setFocusPolicy(Qt.StrongFocus)
        self.setEditable(True)

        # add a filter model to filter matching items
        self.pFilterModel = QSortFilterProxyModel(self)
        self.pFilterModel.setFilterCaseSensitivity(Qt.CaseInsensitive)
        self.pFilterModel.setSourceModel(self.model())

        # add a completer, which uses the filter model
        self.completer = QCompleter(self.pFilterModel, self)
        # always show all (filtered) completions
        self.completer.setCompletionMode(QCompleter.UnfilteredPopupCompletion)
        self.setCompleter(self.completer)

        # connect signals
        self.lineEdit().textEdited[unicode].connect(self.pFilterModel.setFilterFixedString)
        self.completer.activated.connect(self.on_completer_activated)


    # on selection of an item from the completer, select the corresponding item from combobox
    def on_completer_activated(self, text):
        if text:
            index = self.findText(text)
            self.setCurrentIndex(index)


    # on model change, update the models of the filter and completer as well
    def setModel(self, model):
        super(ExtendedComboBox, self).setModel(model)
        self.pFilterModel.setSourceModel(model)
        self.completer.setModel(self.pFilterModel)


    # on model column change, update the model column of the filter and completer as well
    def setModelColumn(self, column):
        self.completer.setCompletionColumn(column)
        self.pFilterModel.setFilterKeyColumn(column)
        super(ExtendedComboBox, self).setModelColumn(column)


if __name__ == "__main__":
    import sys
    from PyQt4.QtGui import QStringListModel, QApplication, \
        QStandardItemModel, QStandardItem, QVBoxLayout, QHBoxLayout, \
        QMainWindow

    app = QApplication(sys.argv)
    # win = QDialog()
    # win.setMinimumSize(400, 400)
    # layout = QHBoxLayout()
    # win.setLayout(layout)
    string_list = ['hola muchachos', 'adios amigos', 'hello world', 'good bye']
    combo = ExtendedComboBox()
    # combo.addItems(string_list)
    combo.setModel(QStringListModel(string_list))
    # model = QStandardItemModel()
    # for i, word in enumerate(['hola', 'adios', 'hello', 'good bye']):
    #     item = QStandardItem(word)
    #     model.setItem(i, 0, item)
    #
    # combo.setModel(model)
    # layout.addWidget(combo)
    combo.show()
    # win.show()

    sys.exit(app.exec_())

Answer 1

I got the answer from here: Error in model view implemention of GUI in pyqt

After add the model with a parent combo.setModel(QStringListModel(string_list, combo)) , the error is gone away.