Qt QWidget disable re sizing more than minimum size needed

Question

I have a QGridLayout inside a QWidget. I keep adding child QGridLayouts to this. I want the QWidget to resize according to the size needed for child layouts but for the user to be unable to resize it.

MainWindow.cpp (MainWindow is inherited from QWidget)

MainWindow::MainWindow(QWidget *parent) :
    QWidget(parent)
{
    QGridLayout *mainLayout = new QGridLayout();
    {
        AAController *ac1 = new AAController("Ins1");
        AAController *ac2 = new AAController("Ins2");
        AAController *ac3 = new AAController("Ins3");

        mainLayout->addLayout(ac1, 0, 0);
        mainLayout->addLayout(ac2, 0, 1);
        mainLayout->addLayout(ac3, 1, 1);
    }
    setLayout(mainLayout);
}

AAController.cpp (AAController is inherited from QGridLayout)

AAController::AAController(const QString& instrument)
    :_instrument(instrument)
{
    _lblInstrument = new QLabel(_instrument);
    _lblMismatchThreshold = new QLabel("Mismatch threshold : ");
    _lblQuoteVolume = new QLabel("Quote volume : ");
    _btnUpdateAlgo = new QPushButton("Update Algo");
    _spnMismatchThreshold = new QSpinBox();
    _spnQuoteVolume = new QSpinBox();

    this->addWidget(_lblInstrument, 0, 1, 1, 2, Qt::AlignCenter);
    this->addWidget(_lblMismatchThreshold, 1, 0, 1, 2);
    this->addWidget(_lblQuoteVolume, 2, 0, 1, 2);
    this->addWidget(_btnUpdateAlgo, 3, 2, 1, 2);
    this->addWidget(_spnMismatchThreshold, 1, 3);
    this->addWidget(_spnQuoteVolume, 2, 3);

    setSizeConstraint(SetFixedSize);
}

I get something like this:

But at the moment I can resize this like:

enter image description here

I want to disable such resizing. How do I do this?

Just set your MainWindow to Fixed Size. When adding Children set it to Minimum and set it back to fixed size after. — Sebastian Lange, Feb 14 '14 at 08:23
Probably not duplicate, since its no StatusBar nor a QDialog. — Sebastian Lange, Feb 14 '14 at 08:24
@SebastianLange: Your method results in a fixed size window. But larger than the minimum as in the first image above. — nakiya, Feb 14 '14 at 08:28
`setFixedSize(0,0)` in `MainWindow` works. It shows the resize cursor at the window's border but actually can't resize. — nakiya, Feb 14 '14 at 08:57

thuga · Accepted Answer · 2014-02-14T09:08:23.747

3

Try this in your main window:

this->layout()->setSizeConstraint(QLayout::SetFixedSize);

This is the result i got:

enter image description here

edited Feb 14 '14 at 09:08

answered Feb 14 '14 at 08:54

thuga

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Please have a look at the comment to SebastianLange above – nakiya Feb 14 '14 at 08:56
@nakiya See my edit. Is this the result you're looking for? – thuga Feb 14 '14 at 09:08

Qt QWidget disable re sizing more than minimum size needed

1 Answers1