qwt_widget_overlay.h

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   Uwe Rathmann
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *****************************************************************************/

#ifndef QWT_WIDGET_OVERLAY_H
#define QWT_WIDGET_OVERLAY_H

#include "qwt_global.h"
#include <qwidget.h>
#include <qregion.h>

class QPainter;

class QWT_EXPORT QwtWidgetOverlay: public QWidget
{
public:
    enum MaskMode
    {
        NoMask,

        MaskHint,

        AlphaMask
    };

    enum RenderMode
    {
        AutoRenderMode,

        CopyAlphaMask,

        DrawOverlay
    };

    QwtWidgetOverlay( QWidget* );
    virtual ~QwtWidgetOverlay();

    void setMaskMode( MaskMode );
    MaskMode maskMode() const;

    void setRenderMode( RenderMode );
    RenderMode renderMode() const;

    void updateOverlay();

    virtual bool eventFilter( QObject *, QEvent *);

protected:
    virtual void paintEvent( QPaintEvent* event );
    virtual void resizeEvent( QResizeEvent* event );

    virtual QRegion maskHint() const;

    virtual void drawOverlay( QPainter *painter ) const = 0;

private:
    void updateMask();
    void draw( QPainter * ) const;

private:
    class PrivateData;
    PrivateData *d_data;
};

#endif