Qt图片旋转

Qt图片旋转

开发过程中突然遇到有个按钮图标需要旋转的需求，就找了下实现旋转的实现方法，以下是实现的代码。
这里我继承了QAbstractButton类，重新绘制按钮的图片，在需要旋转的时候旋转

class spinButton : public QAbstractButton{
    Q_OBJECT
public:
    spinButton(QWidget *parent = nullptr);
    void setIcons(QIcon ic);
    void start();
    void stop();

signals:
public slots:
    void timeOut();
protected:
    virtual void paintEvent(QPaintEvent *e);
private:
    QPixmap Icon;
    int angle = 0;
    bool isRotate = false;
    QTimer *timer = nullptr;

};

TreeWidgetEx::spinButton::spinButton(QWidget *parent) : QAbstractButton(parent)
{
    Icon = QPixmap();
    timer = new QTimer(this);
    connect(tim,SIGNAL(timeout()),this,SLOT(timeOut()));
    angle = 0;
}

void TreeWidgetEx::spinButton::setIcons(QIcon ic)
{
    Icon = ic;
}

void TreeWidgetEx::spinButton::start()
{
    angle = 0;
    tim->start(20);
}

void TreeWidgetEx::spinButton::stop()
{
    tim->stop();
    angle = 0;
    update();
}

void TreeWidgetEx::spinButton::timeOut()
{
    angle += 20;
    if(angle >= 360)
        angle = 0;

    update();

}

void TreeWidgetEx::spinButton::paintEvent(QPaintEvent *e)
{
    Q_UNUSED(e)

    QPainter paint(this);
    paint.save();
    paint.setRenderHints(QPainter::Antialiasing, true);

    QPixmap pixmap = Icon.scaled(this->width()-10,this->height()-10,Qt::KeepAspectRatio, Qt::SmoothTransformation);

    paint.rotate(angle);//坐标旋转
    //经分析，应使图片中心，对应原点
    paint.drawPixmap(-pixmap.width()/2,-pixmap.height()/2,pixmap);

    paint.restore();
}
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