gradients.h Example File

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  #ifndef GRADIENTS_H
  #define GRADIENTS_H

  #include "arthurwidgets.h"

  class QRadioButton;

  class HoverPoints;

  class ShadeWidget : public QWidget
  {
      Q_OBJECT

  public:
      enum ShadeType {
          RedShade,
          GreenShade,
          BlueShade,
          ARGBShade
      };

      ShadeWidget(ShadeType type, QWidget *parent);

      void setGradientStops(const QGradientStops &stops);

      void paintEvent(QPaintEvent *e) Q_DECL_OVERRIDE;

      QSize sizeHint() const Q_DECL_OVERRIDE { return QSize(150, 40); }
      QPolygonF points() const;

      HoverPoints *hoverPoints() const { return m_hoverPoints; }

      uint colorAt(int x);

  signals:
      void colorsChanged();

  private:
      void generateShade();

      ShadeType m_shade_type;
      QImage m_shade;
      HoverPoints *m_hoverPoints;
      QLinearGradient m_alpha_gradient;
  };

  class GradientEditor : public QWidget
  {
      Q_OBJECT

  public:
      GradientEditor(QWidget *parent);

      void setGradientStops(const QGradientStops &stops);

  public slots:
      void pointsUpdated();

  signals:
      void gradientStopsChanged(const QGradientStops &stops);

  private:
      ShadeWidget *m_red_shade;
      ShadeWidget *m_green_shade;
      ShadeWidget *m_blue_shade;
      ShadeWidget *m_alpha_shade;
  };

  class GradientRenderer : public ArthurFrame
  {
      Q_OBJECT

  public:
      GradientRenderer(QWidget *parent);
      void paint(QPainter *p) Q_DECL_OVERRIDE;

      QSize sizeHint() const Q_DECL_OVERRIDE { return QSize(400, 400); }

      HoverPoints *hoverPoints() const { return m_hoverPoints; }
      void mousePressEvent(QMouseEvent *e) Q_DECL_OVERRIDE;

  public slots:
      void setGradientStops(const QGradientStops &stops);

      void setPadSpread() { m_spread = QGradient::PadSpread; update(); }
      void setRepeatSpread() { m_spread = QGradient::RepeatSpread; update(); }
      void setReflectSpread() { m_spread = QGradient::ReflectSpread; update(); }

      void setLinearGradient() { m_gradientType = Qt::LinearGradientPattern; update(); }
      void setRadialGradient() { m_gradientType = Qt::RadialGradientPattern; update(); }
      void setConicalGradient() { m_gradientType = Qt::ConicalGradientPattern; update(); }

  private:
      QGradientStops m_stops;
      HoverPoints *m_hoverPoints;

      QGradient::Spread m_spread;
      Qt::BrushStyle m_gradientType;
  };

  class GradientWidget : public QWidget
  {
      Q_OBJECT

  public:
      GradientWidget(QWidget *parent);

  public slots:
      void setDefault1() { setDefault(1); }
      void setDefault2() { setDefault(2); }
      void setDefault3() { setDefault(3); }
      void setDefault4() { setDefault(4); }

  private:
      void setDefault(int i);

      GradientRenderer *m_renderer;
      GradientEditor *m_editor;

      QRadioButton *m_linearButton;
      QRadioButton *m_radialButton;
      QRadioButton *m_conicalButton;
      QRadioButton *m_padSpreadButton;
      QRadioButton *m_reflectSpreadButton;
      QRadioButton *m_repeatSpreadButton;

  };

  #endif // GRADIENTS_H