Dynamically resize QIcon without calling setSizeIcon()

Question

I\'m currently struggling with what should be an easy issue to solve. Many widgets support some sort of QSizePolicy. This includes the QPushbutton

Answer 1

To persons who work in C++. Thanks a lot !

pushbuttoniconautoresize.h

#ifndef PUSHBUTTONIMAGEAUTOMATICRESIZE_H
#define PUSHBUTTONIMAGEAUTOMATICRESIZE_H

#include 

class PushButtonIconAutoResize : public QPushButton
{
    Q_OBJECT

public:
    PushButtonIconAutoResize(const QString &text, QWidget *parent=0);
    ~PushButtonIconAutoResize();

private:
    void paintEvent(QPaintEvent *event);

    int pad;
    int minSize;
};

#endif // PUSHBUTTONIMAGEAUTOMATICRESIZE_H

pushbuttoniconautoresize.cpp

#include "pushbuttoniconautoresize.h"

#include 
#include 
#include 
#include 
#include 

PushButtonIconAutoResize::PushButtonIconAutoResize(const QString &text, QWidget *parent)
    : QPushButton(text, parent)
{
    pad = 4;
    minSize = 8;

    this->setSizePolicy(QSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding));
}

PushButtonIconAutoResize::~PushButtonIconAutoResize()
{

}

void PushButtonIconAutoResize::paintEvent( QPaintEvent *event )
{
    QStylePainter painter(this);

    QStyleOptionButton opt;
    this->initStyleOption(&opt);

    QRect r = opt.rect;

    int h = r.height();
    int w = r.width();
    int iconSize = qMax(qMin(h, w) - 2 * this->pad, this->minSize);

    opt.iconSize = QSize(iconSize, iconSize);

    painter.drawControl(QStyle::CE_PushButton, opt);
}