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Thread: how to force widgets update

  1. #1
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    Default how to force widgets update

    Hi, the following code
    Qt Code:
    1. statusLabel = new QLabel(" idle ", this);
    2. statusBar()->addWidget(statusLabel);
    3.  
    4. statusLabel->setText("doing something");
    5. myobject->do_smth_for_minute();
    6. statusLabel->setText("something done");
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    does not update the statusLabel, it just stays "something done". How can I force updating the widget?

  2. #2
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    Default Re: how to force widgets update

    try calling update();
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    Default Re: how to force widgets update

    You are blocking the event loop so the widget can't update itself. Read this article: [wiki]Keeping the GUI Responsive[/wiki].
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  4. #4
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    Default Re: how to force widgets update

    update() does not work (on windows at least). That is the point, I am afraid I need to put a task to a thread, but that just is not right, I do not need it to be responsive in between two updates of the widget, I only want to update it once before and once afterwards.

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    Default Re: how to force widgets update

    an easy way, set a QTimer which will timeout in a few millisec,connect its timeout SIGNAL
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    Default Re: how to force widgets update

    See the part of the article that deals with manually triggering event processing.

    @MorrisLiang: I'm afraid this won't work as event loop is blocked so timers don't fire. update() is called, it just doesn't cause the desired effect.
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