QVBoxLayout - Centering the Top Widget

Drakkhan

Hey, I've got a layout problem. Hoping someone can help.

Background:
I'm building a window that has two widgets in a QVBoxLayout. The top one (thanks to @J.Hilk : here) maintains a square aspect ratio. The bottom has a fixed height and a minimum width.

Problem:
The problem is that when I resize the overall window, the upper widget (forced to be square) sometimes can't stretch across the entire height or width available, and chooses to align left and top. I want it to align center or center depending on which dimension it can't fill.

Some code illustrating my problem:

upperwidget.h:

#ifndef UPPERWIDGET_H
#define UPPERWIDGET_H

#include <QLabel>
#include <QResizeEvent>

class UpperWidget : public QLabel
{
    Q_OBJECT
public:
    explicit UpperWidget(QWidget *parent = 0);

protected:
    virtual void resizeEvent(QResizeEvent *event) Q_DECL_OVERRIDE;

signals:

public slots:

};

#endif // UPPERWIDGET_H

upperwidget.cpp:

#include "upperwidget.h"

UpperWidget::UpperWidget(QWidget *parent) : QLabel(parent)
{

    setText("UpperWidget");
    setFrameStyle(QFrame::Panel | QFrame::Raised);
    setLineWidth(2);
    setAlignment(Qt::AlignCenter | Qt::AlignCenter);
    setMinimumSize(100, 100);


}

void UpperWidget::resizeEvent(QResizeEvent *event)
{
    event->accept();

    if(event->size().width() > event->size().height()){
        QWidget::resize(event->size().height(),event->size().height());
    }else{
        QWidget::resize(event->size().width(),event->size().width());
    }
}

lowerwidget.h:

#ifndef LOWERWIDGET_H
#define LOWERWIDGET_H

#include <QLabel>

class LowerWidget : public QLabel
{
    Q_OBJECT
public:
    explicit LowerWidget(QWidget *parent = 0);

signals:

public slots:

};

#endif // LOWERWIDGET_H

lowerwidget.cpp:

#include "lowerwidget.h"

LowerWidget::LowerWidget(QWidget *parent) : QLabel(parent)
{
    setText("LowerWidget");
    setFrameStyle(QFrame::Panel | QFrame::Raised);
    setLineWidth(2);
    setAlignment(Qt::AlignCenter | Qt::AlignCenter);
    setMinimumSize(100, 50);
    setMaximumHeight(50);

}

main.cpp:

#include <QApplication>
#include <QWidget>
#include <QLayout>

#include "upperwidget.h"
#include "lowerwidget.h"

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

 QWidget *window = new QWidget;
 UpperWidget *upperWidget = new UpperWidget(window);
 LowerWidget *lowerWidget = new LowerWidget(window);
 QVBoxLayout *theLayout = new QVBoxLayout;

 theLayout->addWidget(upperWidget, 0, 0);
 theLayout->addWidget(lowerWidget, 0, 0);
 window->setLayout(theLayout);
 window->show();

 return app.exec();
}

SGaist

Hi,

From the top of my head, you can try to set alignment flag to Qt::AlignHCenter rather than 0.