QVBoxLayout vs Qlabel - resizing issue

[migel]

simple adding lable into QVBoxLayout layout does not resize label .

QLabel *label = new QLabel("test");
QVBoxLayout *layout = new QVBoxLayout;
QWidget *widget = new QWidget;
widget->setLayout(layout);
layout->addWidget(label);

QLabel *label = new QLabel("test");
QVBoxLayout *layout = new QVBoxLayout;
QWidget *widget = new QWidget;
widget->setLayout(layout);
layout->addWidget(label);

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But when I add QTabWidget it resizes just fine.

I have tried this scenario using Q Designer and works there.

I have tried changing different sizePolicy of the label and widget, no luck.

what I am doing wrong ??

[ChrisW67]

How are you determining that the label does not get resized?

#include <QtGui>
#include <QDebug>
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
    QWidget widget;
    QVBoxLayout *layout = new QVBoxLayout;
    QLabel *label = new QLabel("test");
    layout->addWidget(label);
    widget.setLayout(layout);
 
    qDebug() << widget.size() << label->size();
    widget.show();
    qDebug() << widget.size() << label->size();
    widget.resize(320, 200);
    qDebug() << widget.size() << label->size();
    return app.exec();
}

#include <QtGui>
#include <QDebug>

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    QWidget widget;
    QVBoxLayout *layout = new QVBoxLayout;
    QLabel *label = new QLabel("test");
    layout->addWidget(label);
    widget.setLayout(layout);

    qDebug() << widget.size() << label->size();
    widget.show();
    qDebug() << widget.size() << label->size();
    widget.resize(320, 200);
    qDebug() << widget.size() << label->size();
    return app.exec();
}

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out:

QSize(640, 480) QSize(640, 480) 
QSize(47, 39) QSize(25, 17) 
QSize(320, 200) QSize(298, 178)

QSize(640, 480) QSize(640, 480) 
QSize(47, 39) QSize(25, 17) 
QSize(320, 200) QSize(298, 178)

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Some layout resizing is not done until the widget is displayed, but the label is resized.