QHBoxLayout does not resize when a child does, also other children keep their positions

[Doros]

Hi,
I want to put 2 or 3 labels inside a QHBoxLayout, then resize the first label using an animation.
I succeeded to do that, but sadly not as I expected.
The problem is that the layout doesn't auto resize to content when I change the first label width. Also, the other labels are not pushed or shifted to right.

This is the result (Failed result):

I can do that in Java using JavaFX quite easily. So, I get that (Expected result):

This is my animation code:

QPropertyAnimation *animation = new QPropertyAnimation(ui->label_1, "size"); 
animation->setDuration(10000);
animation->setStartValue(QSize(55, ui->label_1->size().height()));
animation->setEndValue(QSize(600, ui->label_1->size().height()));
animation->setEasingCurve(QEasingCurve::InCurve);
animation->start();

NB: I'm using:

• Linux Mint
• Qt 5.15
• Qt ==> QHBoxLayout, QLabel
• JavaFX ==> HBox, Label

Thank you.

[jsulm]

@Doros Please show how you're using layouts.

[Bonnie]

Yes, please show more. I guess you are not using layouts in the right way.
From what you posted, changing the "size" property of widgets in a layout is already wrong, that should be handled by the layout.

[jsulm]

@Doros As @Bonnie pointed out setting size of a widget which is in a layout is wrong. What you should do is to not to use layouts for this widgets, but size and position them manually.

[Doros]

@Bonnie
@jsulm

I found a convenient solution, that I'm testing.
I handled the size of widgets by using strech property to one of them, then I put the layout it self inside an empty widget to let me to set width, because layout doesn't have a resizing property.

I'm struggling now to continue my application.

Thanks both of you.