Layout is wrong at program start, adjusts once window is resized by hand.

UpsJustInhaledQt

Hello,

I have another problem I'm really stuck on: I created a board game which is resizeable and adjusts the positions of all pieces on the board according to the new size. This happens in resizeEvent of a custom Widget derived from QWidget.

Even if I execute the code inside the constructor, or call resize(size()) at the end of the constructor, nothing happens. However, if I perform this little hack with a timer, after a short period the layout will correctly adjust (just like it will when I resize by hand):

Board::Board(...) {
...
    connect(timer, &QTimer::timeout, this, [this] { resize(size() + QSize(1, 1)); });
    timer->start(2000);
}

Has anyone ever encountered this sort of issue? The Board has a layout which contains a single QLabel (as a background image). By setting the contextMargins, I keep the label centered in the window and its aspect ratio is preserved. Additionally, I have about 30 more QLabel objects, also children of the Board, but not part of the layout. These are moved to fit onto the board accordingly.

I really hope I can resolve this, and make my board look correct instantly, and not using this sort of hack.

P.S.: Another thing which really confuses me: I allocate the board already in my MainWindow. Then I add it as a stackedWidget page and simply set its index as current index when the start button is clicked. However, the timer I set in the Board constructor still only starts running once I change the stackedWidget page to the board widget. Is this to be expected?

SGaist

Hi,

Until your widget is shown it has no size hence calling resize in the constructor will not have the effect you expect.

I think I more or less understand what it is about but can you provide a minimal compilable example that shows that behaviour ?

UpsJustInhaledQt

Until your widget is shown it has no size hence calling resize in the constructor will not have the effect you expect.

You gave me the information I needed, after quick google I came up with the following solution:

void Board::showEvent(QShowEvent *event)
{
    QCoreApplication::postEvent(this, new QResizeEvent(size(), size()));
}

This works as I intend. Thanks again!