imagewidget.h Example File

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#ifndef IMAGEWIDGET_H
#define IMAGEWIDGET_H
#include <QWidget>
#include <QImage>
#include <QtWidgets>
class QGestureEvent;
class QPanGesture;
class QPinchGesture;
class QSwipeGesture;
Q_DECLARE_LOGGING_CATEGORY(lcExample)
class ImageWidget : public QWidget
{
    Q_OBJECT
public:
    ImageWidget(QWidget *parent = 0);
    void openDirectory(const QString &path);
    void grabGestures(const QList<Qt::GestureType> &gestures);
protected:
    bool event(QEvent *event) override;
    void paintEvent(QPaintEvent *event) override;
    void resizeEvent(QResizeEvent *event) override;
    void mouseDoubleClickEvent(QMouseEvent *event) override;
private:
    bool gestureEvent(QGestureEvent *event);
    void panTriggered(QPanGesture*);
    void pinchTriggered(QPinchGesture*);
    void swipeTriggered(QSwipeGesture*);
    QImage loadImage(const QString &fileName);
    void loadImage();
    void goNextImage();
    void goPrevImage();
    void goToImage(int index);
    QString path;
    QStringList files;
    int position;
    QImage prevImage, nextImage;
    QImage currentImage;
    qreal horizontalOffset;
    qreal verticalOffset;
    qreal rotationAngle;
    qreal scaleFactor;
    qreal currentStepScaleFactor;
};
#endif