Qt 5.6 | Qt Widgets | Image Gestures Example | imagewidget.h Example File

Qt 5.6.2 Reference Documentation

# imagewidget.h Example File

gestures/imagegestures/imagewidget.h

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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) Q_DECL_OVERRIDE;
          void paintEvent(QPaintEvent *event) Q_DECL_OVERRIDE;
          void resizeEvent(QResizeEvent *event) Q_DECL_OVERRIDE;
          void mouseDoubleClickEvent(QMouseEvent *event) Q_DECL_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