- Qt 5.5
- Qt Widgets
- Tablet Example
- tabletcanvas.h Example File
- Qt 5.5.1 Reference Documentation

# tabletcanvas.h Example File

widgets/tablet/tabletcanvas.h

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
    **
    ** "Redistribution and use in source and binary forms, with or without
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    #ifndef TABLETCANVAS_H
    #define TABLETCANVAS_H

    #include <QWidget>
    #include <QPixmap>
    #include <QPoint>
    #include <QTabletEvent>
    #include <QColor>
    #include <QBrush>
    #include <QPen>
    #include <QPoint>

    class QPaintEvent;
    class QString;

    class TabletCanvas : public QWidget
    {
        Q_OBJECT

    public:
        enum AlphaChannelType { AlphaPressure, AlphaTilt, NoAlpha };
        enum ColorSaturationType { SaturationVTilt, SaturationHTilt,
                                   SaturationPressure, NoSaturation };
        enum LineWidthType { LineWidthPressure, LineWidthTilt, NoLineWidth };

        TabletCanvas();

        bool saveImage(const QString &file);
        bool loadImage(const QString &file);
        void setAlphaChannelType(AlphaChannelType type)
            { alphaChannelType = type; }
        void setColorSaturationType(ColorSaturationType type)
            { colorSaturationType = type; }
        void setLineWidthType(LineWidthType type)
            { lineWidthType = type; }
        void setColor(const QColor &color)
            { myColor = color; }
        QColor color() const
            { return myColor; }
        void setTabletDevice(QTabletEvent::TabletDevice device)
            { myTabletDevice = device; }
        int maximum(int a, int b)
            { return a > b ? a : b; }

    protected:
        void tabletEvent(QTabletEvent *event) Q_DECL_OVERRIDE;
        void paintEvent(QPaintEvent *event) Q_DECL_OVERRIDE;
        void resizeEvent(QResizeEvent *event) Q_DECL_OVERRIDE;

    private:
        void initPixmap();
        void paintPixmap(QPainter &painter, QTabletEvent *event);
        Qt::BrushStyle brushPattern(qreal value);
        void updateBrush(QTabletEvent *event);

        AlphaChannelType alphaChannelType;
        ColorSaturationType colorSaturationType;
        LineWidthType lineWidthType;
        QTabletEvent::PointerType pointerType;
        QTabletEvent::TabletDevice myTabletDevice;
        QColor myColor;

        QPixmap pixmap;
        QBrush myBrush;
        QPen myPen;
        bool deviceDown;
        QPoint polyLine[3];
    };

    #endif