Qwt User's Guide: QwtPlotGrid Class Reference

# QwtPlotGrid Class Reference

A class which draws a coordinate grid. More...

`#include <qwt_plot_grid.h>`

Inheritance diagram for QwtPlotGrid:
[legend]

List of all members.

## Public Member Functions
| QwtPlotGrid ()
virtual | ~QwtPlotGrid ()
virtual int | rtti () const
void | enableX (bool tf)
bool | xEnabled () const
void | enableY (bool tf)
bool | yEnabled () const
void | enableXMin (bool tf)
bool | xMinEnabled () const
void | enableYMin (bool tf)
bool | yMinEnabled () const
void | setXDiv (const QwtScaleDiv &sx)
const QwtScaleDiv & | xScaleDiv () const
void | setYDiv (const QwtScaleDiv &sy)
const QwtScaleDiv & | yScaleDiv () const
void | setPen (const QPen &p)
void | setMajPen (const QPen &p)
const QPen & | majPen () const
void | setMinPen (const QPen &p)
const QPen & | minPen () const
virtual void | draw (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &rect) const
virtual void | updateScaleDiv (const QwtScaleDiv &xMap, const QwtScaleDiv &yMap)

## Detailed Description

A class which draws a coordinate grid.

The QwtPlotGrid class can be used to draw a coordinate grid. A coordinate grid consists of major and minor vertical and horizontal gridlines. The locations of the gridlines are determined by the X and Y scale divisions which can be assigned with setXDiv() and setYDiv(). The draw() member draws the grid within a bounding rectangle.

## Constructor & Destructor Documentation

QwtPlotGrid::QwtPlotGrid | ( |  | ) | `[explicit]`

Enables major grid, disables minor grid.

QwtPlotGrid::~QwtPlotGrid | ( |  | ) | `[virtual]`

Destructor.

## Member Function Documentation

void QwtPlotGrid::draw | ( | QPainter * | painter,
|  | const QwtScaleMap & | xMap,
|  | const QwtScaleMap & | yMap,
|  | const QRect & | canvasRect |
| ) |  |  | const`[virtual]`

Draw the grid.

The grid is drawn into the bounding rectangle such that gridlines begin and end at the rectangle's borders. The X and Y maps are used to map the scale divisions into the drawing region screen.

Parameters:

  | painter | Painter
  | xMap | X axis map
  | yMap | Y axis
  | canvasRect | Contents rect of the plot canvas

Implements QwtPlotItem.

void QwtPlotGrid::enableX | ( | bool | tf | ) |

Enable or disable vertical gridlines.

Parameters:

  | tf | Enable (true) or disable

See also:
  Minor gridlines can be enabled or disabled with enableXMin()

void QwtPlotGrid::enableXMin | ( | bool | tf | ) |

Enable or disable minor vertical gridlines.

Parameters:

  | tf | Enable (true) or disable

See also:
  enableX()

void QwtPlotGrid::enableY | ( | bool | tf | ) |

Enable or disable horizontal gridlines.

Parameters:

  | tf | Enable (true) or disable

See also:
  Minor gridlines can be enabled or disabled with enableYMin()

void QwtPlotGrid::enableYMin | ( | bool | tf | ) |

Enable or disable minor horizontal gridlines.

Parameters:

  | tf | Enable (true) or disable

See also:
  enableY()

const QPen & QwtPlotGrid::majPen | ( |  | ) | const

Returns:
  the pen for the major gridlines

See also:
  setMajPen(), setMinPen(), setPen()

const QPen & QwtPlotGrid::minPen | ( |  | ) | const

Returns:
  the pen for the minor gridlines

See also:
  setMinPen(), setMajPen(), setPen()

int QwtPlotGrid::rtti | ( |  | ) | const`[virtual]`

Returns:
  QwtPlotItem::Rtti_PlotGrid

Reimplemented from QwtPlotItem.

void QwtPlotGrid::setMajPen | ( | const QPen & | pen | ) |

Assign a pen for the major gridlines

The width of non cosmetic pens is scaled according to the resolution of the paint device.

Parameters:

  | pen | Pen

See also:
  majPen(), setMinPen(), setPen(), QwtPainter::scaledPen()

void QwtPlotGrid::setMinPen | ( | const QPen & | pen | ) |

Assign a pen for the minor gridlines

The width of non cosmetic pens is scaled according to the resolution of the paint device.

Parameters:

  | pen | Pen

See also:
  minPen(), setMajPen(), setPen(), QwtPainter::scaledPen()

void QwtPlotGrid::setPen | ( | const QPen & | pen | ) |

Assign a pen for both major and minor gridlines

The width of non cosmetic pens is scaled according to the resolution of the paint device.

Parameters:

  | pen | Pen

See also:
  setMajPen(), setMinPen(), QwtPainter::scaledPen()

void QwtPlotGrid::setXDiv | ( | const QwtScaleDiv & | scaleDiv | ) |

Assign an x axis scale division

Parameters:

  | scaleDiv | Scale division

void QwtPlotGrid::setYDiv | ( | const QwtScaleDiv & | scaleDiv | ) |

Assign a y axis division

Parameters:

  | scaleDiv | Scale division

void QwtPlotGrid::updateScaleDiv | ( | const QwtScaleDiv & | xScaleDiv,
|  | const QwtScaleDiv & | yScaleDiv |
| ) |  |  | `[virtual]`

Update the grid to changes of the axes scale division

Parameters:

  | xScaleDiv | Scale division of the x-axis
  | yScaleDiv | Scale division of the y-axis

See also:
  QwtPlot::updateAxes()

Reimplemented from QwtPlotItem.

bool QwtPlotGrid::xEnabled | ( |  | ) | const

Returns:
  true if vertical gridlines are enabled

See also:
  enableX()

bool QwtPlotGrid::xMinEnabled | ( |  | ) | const

Returns:
  true if minor vertical gridlines are enabled

See also:
  enableXMin()

const QwtScaleDiv & QwtPlotGrid::xScaleDiv | ( |  | ) | const

Returns:
  the scale division of the x axis

bool QwtPlotGrid::yEnabled | ( |  | ) | const

Returns:
  true if horizontal gridlines are enabled

See also:
  enableY()

bool QwtPlotGrid::yMinEnabled | ( |  | ) | const

Returns:
  true if minor horizontal gridlines are enabled

See also:
  enableYMin()

const QwtScaleDiv & QwtPlotGrid::yScaleDiv | ( |  | ) | const

Returns:
  the scale division of the y axis