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Thread: How can size of QMainWindow's central widget be managed?

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    Question How can size of QMainWindow's central widget be managed?

    Hi,
    I have a main window with a central widget which can grow horizontally when needed but should not grow vertically (just like horizontal slider) along-with 4 dock widgets. Problem is that when the main window's size is increased, central widget's vertical size is also increased, which should not be happening. I have tried
    Qt Code:
    1. setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::Fixed);
    To copy to clipboard, switch view to plain text mode 
    with no success.
    Can you please show me the way?
    Regards,

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    Default Re: How can size of QMainWindow's central widget be managed?

    Try setting a maximum height to the widget.
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    Default Re: How can size of QMainWindow's central widget be managed?

    Quote Originally Posted by high_flyer View Post
    Try setting a maximum height to the widget.
    I tried with
    Qt Code:
    1. setFixedHeight(sizeHint().height());
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    Now the widget's vertical size remains constant but the area which is supposed to be occupied by central widget is still not restricted resulting in empty area below the widget.

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    Default Re: How can size of QMainWindow's central widget be managed?

    Why should it be restricted? You said you didn't want the central widget size to change and it doesn't change. You don't want the main window size to change as well? If so, then either set its maximum height or set a layout constraint on it.
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    Default Re: How can size of QMainWindow's central widget be managed?

    Quote Originally Posted by wysota View Post
    Why should it be restricted? You said you didn't want the central widget size to change and it doesn't change. You don't want the main window size to change as well? If so, then either set its maximum height or set a layout constraint on it.
    Yes, now height of central widget does not change but what's the point of having empty space below it when that space can be effectively used by other dock widgets?

    Please look at the following screen-shots for a better idea.
    Optimum size:


    After increasing window's size:

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    Default Re: How can size of QMainWindow's central widget be managed?

    I don't know if it is the best way to do it, but I would use a QWidget with two QWidgets on it. Set the central widget to the parent, and give the parent a horizontal layout. Put the things you want to stay constant on the top widget and give that widget a fixed size. The bottom widget, with your list of songs will expand then as necessary.

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    Default Re: How can size of QMainWindow's central widget be managed?

    Quote Originally Posted by JPNaude View Post
    I don't know if it is the best way to do it, but I would use a QWidget with two QWidgets on it. Set the central widget to the parent, and give the parent a horizontal layout. Put the things you want to stay constant on the top widget and give that widget a fixed size. The bottom widget, with your list of songs will expand then as necessary.
    This is good only for simple case not when you have a number of dock widgets giving you the complete control over the placement of each dock.


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    Default Re: How can size of QMainWindow's central widget be managed?

    Hi, I'm facing the exact same problem. Have you already found a solution for it? If so, would you please share it?

    Thanx in advance
    Jonny

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    Default Re: How can size of QMainWindow's central widget be managed?

    What problem? This thread discusses correct operation of the Qt layout system

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    Default Having the same issue with resizing

    I'm facing the same issue and I haven't found anyone who appears to have solved it, at least in a way that Google can find.

    Like the OP, I have a central widget and a number of dockwidgets. In my case the dockwidgets are to the right of the central widget.

    When the main window is resized, I want the dock widgets to grow to fill the horizontal space and the central widget to remain fixed. Yet, of course, the exact opposite happens.

    And the central widget is immune to any attempts at setting a size policy.

    The behavior I describe seems like it should be the standard behavior, yet it's apparently very difficult to achieve.

    Is there any simple way to have dockwidgets expand to fill the space while the central widget remains fixed?

    qt_resize_bug.png
    Last edited by alketi; 28th March 2014 at 21:47.

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