# Qwt User's Guide: QwtCompassMagnetNeedle Class Reference

Qwt User's Guide 5.2.3

- Main Page
- Related Pages
- Classes

- Class List
- Class Index
- Class Hierarchy
- Class Members

Public Types | Public Member Functions | Static Public Member Functions | Static Protected Member Functions
QwtCompassMagnetNeedle Class Reference

`#include <qwt_dial_needle.h>`

Inheritance diagram for QwtCompassMagnetNeedle:
[legend]

List of all members.

## Public Types

enum | Style { TriangleStyle, ThinStyle }

## Public Member Functions

| QwtCompassMagnetNeedle (Style=TriangleStyle, const QColor &light=Qt::white, const QColor &dark=Qt::red)
virtual void | draw (QPainter *, const QPoint &, int length, double direction, QPalette::ColorGroup=QPalette::Active) const
Public Member Functions inherited from QwtDialNeedle
| QwtDialNeedle ()
virtual | ~QwtDialNeedle ()
const QPalette & | palette () const
virtual void | setPalette (const QPalette &)

## Static Public Member Functions

static void | drawThinNeedle (QPainter *, const QPalette &, QPalette::ColorGroup, const QPoint &, int length, double direction)
static void | drawTriangleNeedle (QPainter *, const QPalette &, QPalette::ColorGroup, const QPoint &, int length, double direction)

## Static Protected Member Functions

static void | drawPointer (QPainter *painter, const QBrush &brush, int colorOffset, const QPoint &center, int length, int width, double direction)
Static Protected Member Functions inherited from QwtDialNeedle
static void | drawKnob (QPainter *, const QPoint &pos, int width, const QBrush &, bool sunken)

## Detailed Description

A magnet needle for compass widgets.

A magnet needle points to two opposite directions indicating north and south.

The following colors are used:

- QColorGroup::Light
  Used for pointing south
- QColorGroup::Dark
  Used for pointing north
- QColorGroup::Base
  Knob (ThinStyle only)

See also:
  QwtDial, QwtCompass

## Member Function Documentation

void QwtCompassMagnetNeedle::draw | ( | QPainter * | painter,
|  | const QPoint & | center,
|  | int | length,
|  | double | direction,
|  | QPalette::ColorGroup | colorGroup = `QPalette::Active`
| ) |  | const

virtual

Draw the needle

Parameters:

  painter | Painter
  center | Center of the dial, start position for the needle
  length | Length of the needle
  direction | Direction of the needle, in degrees counter clockwise
  colorGroup | Color group, used for painting

Implements QwtDialNeedle.

void QwtCompassMagnetNeedle::drawPointer | ( | QPainter * | painter,
|  | const QBrush & | brush,
|  | int | colorOffset,
|  | const QPoint & | center,
|  | int | length,
|  | int | width,
|  | double | direction
| ) |  |

staticprotected

Draw a compass needle

Parameters:

  painter | Painter
  brush | Brush
  colorOffset | Color offset
  center | Center, where the needle starts
  length | Length of the needle
  width | Width of the needle
  direction | Direction

void QwtCompassMagnetNeedle::drawThinNeedle | ( | QPainter * | painter,
|  | const QPalette & | palette,
|  | QPalette::ColorGroup | colorGroup,
|  | const QPoint & | center,
|  | int | length,
|  | double | direction
| ) |  |

static

Draw a compass needle

Parameters:

  painter | Painter
  palette | Palette
  colorGroup | Color group
  center | Center, where the needle starts
  length | Length of the needle
  direction | Direction

void QwtCompassMagnetNeedle::drawTriangleNeedle | ( | QPainter * | painter,
|  | const QPalette & | palette,
|  | QPalette::ColorGroup | colorGroup,
|  | const QPoint & | center,
|  | int | length,
|  | double | direction
| ) |  |

static

Draw a compass needle

Parameters:

  painter | Painter
  palette | Palette
  colorGroup | Color group
  center | Center, where the needle starts
  length | Length of the needle
  direction | Direction