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) override;

     QSize sizeHint() const 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) override;

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

     HoverPoints *hoverPoints() const { return m_hoverPoints; }
     void mousePressEvent(QMouseEvent *e) 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); }
     void setPreset()     { changePresetBy(0); }
     void setPrevPreset() { changePresetBy(-1); }
     void setNextPreset() { changePresetBy(1); }

 private:
     void setDefault(int i);
     void updatePresetName();
     void changePresetBy(int indexOffset);

     GradientRenderer *m_renderer;
     GradientEditor *m_editor;

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

     int m_presetIndex = 0;
 };

 #endif // GRADIENTS_H