<![CDATA[A bug? QBasicTimer::start: QBasicTimer can only be used with threads started with QThread]]>Hi,all:
I have encountered an interesting problem.

Qt5.14.1 + VS2017 32bit + Win 10

I have a exe project and an MainWindow project. exe to show MainWindow.

Scene 1: exe + QPluginLoader(MainWindow), call MainWindow as a qt plugin, when i close ,it says:

QBasicTimer::start: QBasicTimer can only be used with threads started with QThread

especially when you drag a QComboBox to the ui.
without QComboBox, it says nothing.

Scene 2:exe + QLibrary("Mainwindow.dll"), call MainWindow as a dynamic library, when i colse ,it says nothing. every goes OK.
even I added QComboBox to the Ui.

I donot use any qthread, or qtimer. only a new mainwindow skeleton project from widzard.
Anyone has this problem ,and how does it happen?
thanks.

]]>https://forum.qt.io/topic/131609/a-bug-qbasictimer-start-qbasictimer-can-only-be-used-with-threads-started-with-qthreadRSS for NodeSat, 26 Sep 2026 04:34:26 GMTMon, 01 Nov 2021 07:18:45 GMT60<![CDATA[Reply to A bug? QBasicTimer::start: QBasicTimer can only be used with threads started with QThread on Mon, 27 May 2024 06:55:10 GMT]]>Just chiming in for search engine posterity, in case this helps anyone: I was getting this error because I was inadvertently delete-ing a QComboBox after my QApplication instance had already been destroyed.

]]>https://forum.qt.io/post/800950https://forum.qt.io/post/800950Mon, 27 May 2024 06:55:10 GMT<![CDATA[Reply to A bug? QBasicTimer::start: QBasicTimer can only be used with threads started with QThread on Wed, 03 Nov 2021 09:02:52 GMT]]>@QtTester Before you quit your application:

  1. Make sure that your MainWindow is closed and deleted
  2. Call QPluginLoader::unload()

Does the warning message still appear?

]]>https://forum.qt.io/post/688164https://forum.qt.io/post/688164Wed, 03 Nov 2021 09:02:52 GMT<![CDATA[Reply to A bug? QBasicTimer::start: QBasicTimer can only be used with threads started with QThread on Wed, 03 Nov 2021 08:39:51 GMT]]>@Kent-Dorfman
I do think it's a qt bug. When i load other UI with QtPlugLoader just inherited from QWidget, the warning will not appear.

]]>https://forum.qt.io/post/688144https://forum.qt.io/post/688144Wed, 03 Nov 2021 08:39:51 GMT<![CDATA[Reply to A bug? QBasicTimer::start: QBasicTimer can only be used with threads started with QThread on Tue, 02 Nov 2021 03:15:58 GMT]]>that doesn't seem right. You should be able to instantiate a Qtimer or similar in any class derived from QObject.

]]>https://forum.qt.io/post/687872https://forum.qt.io/post/687872Tue, 02 Nov 2021 03:15:58 GMT