Newer
Older
/* -*- 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
#define QWT_PICKER 1
#include "qwt_global.h"
#include "qwt_text.h"
#include "qwt_event_pattern.h"
#include <qobject.h>
#include <qpen.h>
#include <qfont.h>
#include <qrect.h>
class QWidget;
class QMouseEvent;
class QWheelEvent;
class QKeyEvent;
class QwtPickerMachine;
QwtPicker filters all enter, leave, mouse and keyboard events of a widget
and translates them into an array of selected points.
The way how the points are collected depends on type of state machine
that is connected to the picker. Qwt offers a couple of predefined
state machines for selecting:
- Nothing\n
QwtPickerTrackerMachine
- Single points\n
QwtPickerClickPointMachine, QwtPickerDragPointMachine
- Rectangles\n
QwtPickerClickRectMachine, QwtPickerDragRectMachine
- Polygons\n
QwtPickerPolygonMachine
While these state machines cover the most common ways to collect points
it is also possible to implement individual machines as well.
QwtPicker translates the picked points into a selection using the
adjustedPoints() method. adjustedPoints() is intended to be reimplemented
to fix up the selection according to application specific requirements.
(F.e. when an application accepts rectangles of a fixed aspect ratio only.)
Optionally QwtPicker support the process of collecting points by a
rubber band and tracker displaying a text for the current mouse
position.
picker->setTrackerMode(QwtPicker::ActiveOnly);
picker->setRubberBand(QwtPicker::RectRubberBand); \endverbatim\n
- begin()\n
Activate/Initialize the selection.
- append()\n
Add a new point
- move() \n
Change the position of the last point.
- remove()\n
Remove the last point.
- end()\n
Terminate the selection and call accept to validate the picked points.
The picker is active (isActive()), between begin() and end().
In active state the rubber band is displayed, and the tracker is visible
in case of trackerMode is ActiveOnly or AlwaysOn.
The cursor can be moved using the arrow keys. All selections can be aborted
using the abort key. (QwtEventPattern::KeyPatternCode)
\warning In case of QWidget::NoFocus the focus policy of the observed
widget is set to QWidget::WheelFocus and mouse tracking
or if trackerMode() is AlwayOn.
*/
class QWT_EXPORT QwtPicker: public QObject, public QwtEventPattern
{
Q_OBJECT
Q_PROPERTY( bool isEnabled READ isEnabled WRITE setEnabled )
Q_PROPERTY( ResizeMode resizeMode READ resizeMode WRITE setResizeMode )
Q_PROPERTY( DisplayMode trackerMode READ trackerMode WRITE setTrackerMode )
Q_PROPERTY( QPen trackerPen READ trackerPen WRITE setTrackerPen )
Q_PROPERTY( QFont trackerFont READ trackerFont WRITE setTrackerFont )
Q_PROPERTY( RubberBand rubberBand READ rubberBand WRITE setRubberBand )
Q_PROPERTY( QPen rubberBandPen READ rubberBandPen WRITE setRubberBandPen )
The default value is QwtPicker::NoRubberBand.
\sa setRubberBand(), rubberBand()
//! A horizontal line ( only for QwtPickerMachine::PointSelection )
//! A vertical line ( only for QwtPickerMachine::PointSelection )
//! A crosshair ( only for QwtPickerMachine::PointSelection )
//! A rectangle ( only for QwtPickerMachine::RectSelection )
//! An ellipse ( only for QwtPickerMachine::RectSelection )
//! A polygon ( only for QwtPickerMachine::PolygonSelection )
/*!
Values >= UserRubberBand can be used to define additional
rubber bands.
*/
\brief Display mode
\sa setTrackerMode(), trackerMode(), isActive()
Controls what to do with the selected points of an active
selection when the observed widget is resized.
The default value is QwtPicker::Stretch.
\sa setResizeMode()
enum ResizeMode
{
//! All points are scaled according to the new size,
explicit QwtPicker( QWidget *parent );
explicit QwtPicker( RubberBand rubberBand,
DisplayMode trackerMode, QWidget * );
void setStateMachine( QwtPickerMachine * );
const QwtPickerMachine *stateMachine() const;
QwtPickerMachine *stateMachine();
QFont trackerFont() const;
bool isEnabled() const;
bool isActive() const;
QWidget *parentWidget();
const QWidget *parentWidget() const;
virtual QPainterPath pickArea() const;
virtual void drawRubberBand( QPainter * ) const;
virtual void drawTracker( QPainter * ) const;
QPolygon selection() const;
public Q_SLOTS:
void setEnabled( bool );
Q_SIGNALS:
/*!
A signal indicating, when the picker has been activated.
Together with setEnabled() it can be used to implement
selections with more than one picker.
\param on True, when the picker has been activated
*/
void activated( bool on );
A signal emitting the selected points,
/*!
A signal emitted when a point has been appended to the selection
\param pos Position of the appended point.
\sa append(). moved()
*/
A signal emitted whenever the last appended point of the
selection has been moved.
\param pos Position of the moved last point of the selection.
\sa move(), appended()
*/
void moved( const QPoint &pos );
/*!
A signal emitted whenever the last appended point of the
selection has been removed.
\param pos Position of the point, that has been removed
\sa remove(), appended()
*/
void removed( const QPoint &pos );
/*!
A signal emitted when the active selection has been changed.
This might happen when the observed widget is resized.
virtual void append( const QPoint & );
virtual void move( const QPoint & );
virtual void remove();
virtual bool end( bool ok = true );
virtual void widgetMousePressEvent( QMouseEvent * );
virtual void widgetMouseReleaseEvent( QMouseEvent * );
virtual void widgetMouseDoubleClickEvent( QMouseEvent * );
virtual void widgetMouseMoveEvent( QMouseEvent * );
virtual void widgetWheelEvent( QWheelEvent * );
virtual void widgetKeyPressEvent( QKeyEvent * );
virtual void widgetKeyReleaseEvent( QKeyEvent * );
virtual void widgetEnterEvent( QEvent * );
virtual void widgetLeaveEvent( QEvent * );
virtual void stretchSelection( const QSize &oldSize,
const QSize &newSize );
const QwtWidgetOverlay *rubberBandOverlay() const;
const QwtWidgetOverlay *trackerOverlay() const;
const QPolygon &pickedPoints() const;
void init( QWidget *, RubberBand rubberBand, DisplayMode trackerMode );