qwt_picker_machine.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_PICKER_MACHINE
#define QWT_PICKER_MACHINE 1

#include "qwt_global.h"
#include <qlist.h>

class QEvent;
class QwtEventPattern;

class QWT_EXPORT QwtPickerMachine
{
public:
    enum SelectionType
    {
        NoSelection = -1,

        PointSelection,

        RectSelection,

        PolygonSelection
    };

    enum Command
    {
        Begin,
        Append,
        Move,
        Remove,
        End
    };

    QwtPickerMachine( SelectionType );
    virtual ~QwtPickerMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * ) = 0;
    void reset();

    int state() const;
    void setState( int );

    SelectionType selectionType() const;

private:
    const SelectionType d_selectionType;
    int d_state;
};

class QWT_EXPORT QwtPickerTrackerMachine: public QwtPickerMachine
{
public:
    QwtPickerTrackerMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * );
};

class QWT_EXPORT QwtPickerClickPointMachine: public QwtPickerMachine
{
public:
    QwtPickerClickPointMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * );
};

class QWT_EXPORT QwtPickerDragPointMachine: public QwtPickerMachine
{
public:
    QwtPickerDragPointMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * );
};

class QWT_EXPORT QwtPickerClickRectMachine: public QwtPickerMachine
{
public:
    QwtPickerClickRectMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * );
};

class QWT_EXPORT QwtPickerDragRectMachine: public QwtPickerMachine
{
public:
    QwtPickerDragRectMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * );
};

class QWT_EXPORT QwtPickerPolygonMachine: public QwtPickerMachine
{
public:
    QwtPickerPolygonMachine();

    virtual QList<Command> transition(
        const QwtEventPattern &, const QEvent * );
};

#endif