Qwt User's Guide
QwtPlotPicker Class Reference

QwtPlotPicker provides selections on a plot canvas. More...

#include <qwt_plot_picker.h>

Inheritance diagram for QwtPlotPicker:

Signals

void selected (const QPointF &pos)
void selected (const QRectF &rect)
void selected (const QVector< QPointF > &pa)
void appended (const QPointF &pos)
void moved (const QPointF &pos)

Public Member Functions

 QwtPlotPicker (QWidget *canvas)
 Create a plot picker.
virtual ~QwtPlotPicker ()
 Destructor.
 QwtPlotPicker (int xAxis, int yAxis, QWidget *)
 QwtPlotPicker (int xAxis, int yAxis, RubberBand rubberBand, DisplayMode trackerMode, QWidget *)
virtual void setAxis (int xAxis, int yAxis)
int xAxis () const
 Return x axis.
int yAxis () const
 Return y axis.
QwtPlotplot ()
const QwtPlotplot () const
QWidget * canvas ()
const QWidget * canvas () const

Protected Member Functions

QRectF scaleRect () const
QRectF invTransform (const QRect &) const
QRect transform (const QRectF &) const
QPointF invTransform (const QPoint &) const
QPoint transform (const QPointF &) const
virtual QwtText trackerText (const QPoint &) const
virtual QwtText trackerTextF (const QPointF &) const
 Translate a position into a position string.
virtual void move (const QPoint &)
virtual void append (const QPoint &)
virtual bool end (bool ok=true)

Detailed Description

QwtPlotPicker provides selections on a plot canvas.

QwtPlotPicker is a QwtPicker tailored for selections on a plot canvas. It is set to a x-Axis and y-Axis and translates all pixel coordinates into this coordinate system.


Constructor & Destructor Documentation

QwtPlotPicker::QwtPlotPicker ( QWidget *  canvas) [explicit]

Create a plot picker.

The picker is set to those x- and y-axis of the plot that are enabled. If both or no x-axis are enabled, the picker is set to QwtPlot::xBottom. If both or no y-axis are enabled, it is set to QwtPlot::yLeft.

Parameters:
canvasPlot canvas to observe, also the parent object
See also:
QwtPlot::autoReplot(), QwtPlot::replot(), scaleRect()
QwtPlotPicker::QwtPlotPicker ( int  xAxis,
int  yAxis,
QWidget *  canvas 
) [explicit]

Create a plot picker

Parameters:
xAxisSet the x axis of the picker
yAxisSet the y axis of the picker
canvasPlot canvas to observe, also the parent object
See also:
QwtPlot::autoReplot(), QwtPlot::replot(), scaleRect()
QwtPlotPicker::QwtPlotPicker ( int  xAxis,
int  yAxis,
RubberBand  rubberBand,
DisplayMode  trackerMode,
QWidget *  canvas 
) [explicit]

Create a plot picker

Parameters:
xAxisX axis of the picker
yAxisY axis of the picker
rubberBandRubber band style
trackerModeTracker mode
canvasPlot canvas to observe, also the parent object
See also:
QwtPicker, QwtPicker::setSelectionFlags(), QwtPicker::setRubberBand(), QwtPicker::setTrackerMode
QwtPlot::autoReplot(), QwtPlot::replot(), scaleRect()

Member Function Documentation

void QwtPlotPicker::append ( const QPoint &  pos) [protected, virtual]

Append a point to the selection and update rubber band and tracker.

Parameters:
posAdditional point
See also:
isActive, begin(), end(), move(), appended()
Note:
The appended(const QPoint &), appended(const QDoublePoint &) signals are emitted.

Reimplemented from QwtPicker.

void QwtPlotPicker::appended ( const QPointF &  pos) [signal]

A signal emitted when a point has been appended to the selection

Parameters:
posPosition of the appended point.
See also:
append(). moved()
QWidget * QwtPlotPicker::canvas ( )
Returns:
Observed plot canvas
const QWidget * QwtPlotPicker::canvas ( ) const
Returns:
Observed plot canvas
bool QwtPlotPicker::end ( bool  ok = true) [protected, virtual]

Close a selection setting the state to inactive.

Parameters:
okIf true, complete the selection and emit selected signals otherwise discard the selection.
Returns:
True if the selection has been accepted, false otherwise

Reimplemented from QwtPicker.

Reimplemented in QwtPlotZoomer.

QRectF QwtPlotPicker::invTransform ( const QRect &  rect) const [protected]

Translate a rectangle from pixel into plot coordinates

Returns:
Rectangle in plot coordinates
See also:
transform()
QPointF QwtPlotPicker::invTransform ( const QPoint &  pos) const [protected]

Translate a point from pixel into plot coordinates

Returns:
Point in plot coordinates
See also:
transform()
void QwtPlotPicker::move ( const QPoint &  pos) [protected, virtual]

Move the last point of the selection

Parameters:
posNew position
See also:
isActive, begin(), end(), append()
Note:
The moved(const QPoint &), moved(const QDoublePoint &) signals are emitted.

Reimplemented from QwtPicker.

void QwtPlotPicker::moved ( const QPointF &  pos) [signal]

A signal emitted whenever the last appended point of the selection has been moved.

Parameters:
posPosition of the moved last point of the selection.
See also:
move(), appended()
Returns:
Plot widget, containing the observed plot canvas
const QwtPlot * QwtPlotPicker::plot ( ) const
Returns:
Plot widget, containing the observed plot canvas
QRectF QwtPlotPicker::scaleRect ( ) const [protected]
Returns:
Normalized bounding rectangle of the axes
See also:
QwtPlot::autoReplot(), QwtPlot::replot().
void QwtPlotPicker::selected ( const QPointF &  pos) [signal]

A signal emitted in case of QwtPickerMachine::PointSelection.

Parameters:
posSelected point
void QwtPlotPicker::selected ( const QRectF &  rect) [signal]

A signal emitted in case of QwtPickerMachine::RectSelection.

Parameters:
rectSelected rectangle
void QwtPlotPicker::selected ( const QVector< QPointF > &  pa) [signal]

A signal emitting the selected points, at the end of a selection.

Parameters:
paSelected points
void QwtPlotPicker::setAxis ( int  xAxis,
int  yAxis 
) [virtual]

Set the x and y axes of the picker

Parameters:
xAxisX axis
yAxisY axis

Reimplemented in QwtPlotZoomer.

QwtText QwtPlotPicker::trackerText ( const QPoint &  pos) const [protected, virtual]

Translate a pixel position into a position string

Parameters:
posPosition in pixel coordinates
Returns:
Position string

Reimplemented from QwtPicker.

QwtText QwtPlotPicker::trackerTextF ( const QPointF &  pos) const [protected, virtual]

Translate a position into a position string.

In case of HLineRubberBand the label is the value of the y position, in case of VLineRubberBand the value of the x position. Otherwise the label contains x and y position separated by a ',' .

The format for the double to string conversion is "%.4f".

Parameters:
posPosition
Returns:
Position string
QRect QwtPlotPicker::transform ( const QRectF &  rect) const [protected]

Translate a rectangle from plot into pixel coordinates

Returns:
Rectangle in pixel coordinates
See also:
invTransform()
QPoint QwtPlotPicker::transform ( const QPointF &  pos) const [protected]

Translate a point from plot into pixel coordinates

Returns:
Point in pixel coordinates
See also:
invTransform()

List of all members.

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