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); }
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