qwt_picker_machine.h 5.59 KiB
/* -*- 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;
/*!
\brief A state machine for QwtPicker selections
QwtPickerMachine accepts key and mouse events and translates them
into selection commands.
\sa QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode
*/
class QWT_EXPORT QwtPickerMachine
{
public:
/*!
Type of a selection.
\sa selectionType()
*/
enum SelectionType
{
//! The state machine not usable for any type of selection.
NoSelection = -1,
//! The state machine is for selecting a single point.
PointSelection,
//! The state machine is for selecting a rectangle (2 points).
RectSelection,
//! The state machine is for selecting a polygon (many points).
PolygonSelection
};
//! Commands - the output of a state machine
enum Command
{
Begin,
Append,
Move,
Remove,
End
};
QwtPickerMachine( SelectionType );
virtual ~QwtPickerMachine();
//! Transition
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;
};
/*!
\brief A state machine for indicating mouse movements
QwtPickerTrackerMachine supports displaying information
corresponding to mouse movements, but is not intended for
selecting anything. Begin/End are related to Enter/Leave events.
*/
class QWT_EXPORT QwtPickerTrackerMachine: public QwtPickerMachine
{
public:
QwtPickerTrackerMachine();
virtual QList<Command> transition(
const QwtEventPattern &, const QEvent * );
};
/*!
\brief A state machine for point selections
Pressing QwtEventPattern::MouseSelect1 or
QwtEventPattern::KeySelect1 selects a point.
\sa QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode
*/
class QWT_EXPORT QwtPickerClickPointMachine: public QwtPickerMachine
{
public:
QwtPickerClickPointMachine();
virtual QList<Command> transition(
const QwtEventPattern &, const QEvent * );
};
/*!
\brief A state machine for point selections
Pressing QwtEventPattern::MouseSelect1 or QwtEventPattern::KeySelect1
starts the selection, releasing QwtEventPattern::MouseSelect1 or
a second press of QwtEventPattern::KeySelect1 terminates it.
*/
class QWT_EXPORT QwtPickerDragPointMachine: public QwtPickerMachine
{
public:
QwtPickerDragPointMachine();
virtual QList<Command> transition(
const QwtEventPattern &, const QEvent * );
};
/*!
\brief A state machine for rectangle selections
Pressing QwtEventPattern::MouseSelect1 starts
the selection, releasing it selects the first point. Pressing it
again selects the second point and terminates the selection.
Pressing QwtEventPattern::KeySelect1 also starts the
selection, a second press selects the first point. A third one selects
the second point and terminates the selection.
\sa QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode
*/
class QWT_EXPORT QwtPickerClickRectMachine: public QwtPickerMachine{
public:
QwtPickerClickRectMachine();
virtual QList<Command> transition(
const QwtEventPattern &, const QEvent * );
};
/*!
\brief A state machine for rectangle selections
Pressing QwtEventPattern::MouseSelect1 selects
the first point, releasing it the second point.
Pressing QwtEventPattern::KeySelect1 also selects the
first point, a second press selects the second point and terminates
the selection.
\sa QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode
*/
class QWT_EXPORT QwtPickerDragRectMachine: public QwtPickerMachine
{
public:
QwtPickerDragRectMachine();
virtual QList<Command> transition(
const QwtEventPattern &, const QEvent * );
};
/*!
\brief A state machine for line selections
Pressing QwtEventPattern::MouseSelect1 selects
the first point, releasing it the second point.
Pressing QwtEventPattern::KeySelect1 also selects the
first point, a second press selects the second point and terminates
the selection.
A common use case of QwtPickerDragLineMachine are pickers for
distance measurements.
\sa QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode
*/
class QWT_EXPORT QwtPickerDragLineMachine: public QwtPickerMachine
{
public:
QwtPickerDragLineMachine();
virtual QList<Command> transition(
const QwtEventPattern &, const QEvent * );
};
/*!
\brief A state machine for polygon selections
Pressing QwtEventPattern::MouseSelect1 or QwtEventPattern::KeySelect1
starts the selection and selects the first point, or appends a point.
Pressing QwtEventPattern::MouseSelect2 or QwtEventPattern::KeySelect2
appends the last point and terminates the selection.
\sa QwtEventPattern::MousePatternCode, QwtEventPattern::KeyPatternCode
*/
class QWT_EXPORT QwtPickerPolygonMachine: public QwtPickerMachine
{
public:
QwtPickerPolygonMachine();
virtual QList<Command> transition( const QwtEventPattern &, const QEvent * );
};
#endif