Main Page | Class Hierarchy | Alphabetical List | Class List | File List | Class Members | File Members | Related Pages

# QwtThermo Class Reference

Inheritance diagram for QwtThermo:

[legend]
Collaboration diagram for QwtThermo:

[legend]
List of all members.

## Detailed Description

The Thermometer Widget.

QwtThermo is a widget which displays a value in an interval. It supports:

- a horizontal or vertical layout;
- a range;
- a scale;
- an alarm level.

By default, the scale and range run over the same interval of values. QwtScaleIf::setScale() changes the interval of the scale and allows easy conversion between physical units. The example shows how to make the scale indicate in degrees Fahrenheit and to set the value in degrees Kelvin:

    #include <qapplication.h>
    #include <qwt_thermo.h>

    double Kelvin2Fahrenheit(double kelvin)
    {
        // see http://en.wikipedia.org/wiki/Kelvin
        return 1.8*kelvin - 459.67;
    }

    int main(int argc, char **argv)
    {
        const double minKelvin = 0.0;
        const double maxKelvin = 500.0;

        QApplication a(argc, argv);
        QwtThermo t;
        t.setRange(minKelvin, maxKelvin);
        t.setScale(Kelvin2Fahrenheit(minKelvin), Kelvin2Fahrenheit(maxKelvin));
        // set the value in Kelvin but the scale displays in Fahrenheit
        // 273.15 Kelvin = 0 Celsius = 32 Fahrenheit
        t.setValue(273.15);
        a.setMainWidget(&t);
        t.show();
        return a.exec();
    }

Todo:
  Improve the support for a logarithmic range and/or scale.

Definition at line 67 of file qwt_thermo.h.

## Public Types
enum | ScalePos { None, Left, Right, Top, Bottom }
## Public Slots
void | setValue (double val)
## Public Member Functions
| QwtThermo (QWidget *parent=0, const char *name=0)
virtual | ~QwtThermo ()
void | setOrientation (Qt::Orientation o, ScalePos s)
void | setScalePosition (ScalePos s)
ScalePos | scalePosition () const
void | setBorderWidth (int w)
int | borderWidth () const
void | setFillBrush (const QBrush &b)
const QBrush & | fillBrush () const
void | setFillColor (const QColor &c)
const QColor & | fillColor () const
void | setAlarmBrush (const QBrush &b)
const QBrush & | alarmBrush () const
void | setAlarmColor (const QColor &c)
const QColor & | alarmColor () const
void | setAlarmLevel (double v)
double | alarmLevel () const
void | setAlarmEnabled (bool tf)
bool | alarmEnabled () const
void | setPipeWidth (int w)
int | pipeWidth () const
void | setMaxValue (double v)
double | maxValue () const
void | setMinValue (double v)
double | minValue () const
double | value () const
void | setRange (double vmin, double vmax, bool lg=FALSE)
void | setMargin (int m)
virtual QSize | sizeHint () const
virtual QSize | minimumSizeHint () const
virtual QSizePolicy | sizePolicy () const
## Protected Member Functions
void | draw (QPainter *p, const QRect &update_rect)
void | drawThermo (QPainter *p)
void | layoutThermo (bool update=TRUE)
virtual void | scaleChange ()
virtual void | fontChange (const QFont &oldFont)
virtual void | paintEvent (QPaintEvent *e)
virtual void | resizeEvent (QResizeEvent *e)

## Constructor & Destructor Documentation

QwtThermo::QwtThermo | ( | QWidget * | parent = `0`,
|  | const char * | name = `0`
| ) |

| Constructor. Definition at line 20 of file qwt_thermo.cpp.

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

| Destructor. Definition at line 27 of file qwt_thermo.cpp.

## Member Function Documentation

const QBrush & QwtThermo::alarmBrush | ( |  | ) | const

| Return the liquid brush above the alarm threshold. Definition at line 529 of file qwt_thermo.cpp.

const QColor & QwtThermo::alarmColor | ( |  | ) | const

| Return the liquid color above the alarm threshold. Definition at line 545 of file qwt_thermo.cpp.

bool QwtThermo::alarmEnabled | ( |  | ) | const

| Return if the alarm threshold is enabled or disabled. Definition at line 611 of file qwt_thermo.cpp.

double QwtThermo::alarmLevel | ( |  | ) | const

| Return the alarm threshold. Definition at line 559 of file qwt_thermo.cpp.

int QwtThermo::borderWidth | ( |  | ) | const

| Return the border width of the thermometer pipe. Definition at line 457 of file qwt_thermo.cpp.

void QwtThermo::draw | ( | QPainter * | p,
|  | const QRect & | update_rect
| ) | `[protected]`

| Draw the whole QwtThermo. Definition at line 80 of file qwt_thermo.cpp. References QwtScaleDraw::draw(), drawThermo(), and QwtScaleIf::scaleDraw(). Referenced by paintEvent().

void QwtThermo::drawThermo | ( | QPainter * | p | ) | `[protected]`

| Redraw the liquid in thermometer pipe. Definition at line 288 of file qwt_thermo.cpp. References QwtDiMap::limTransform(). Referenced by draw().

const QBrush & QwtThermo::fillBrush | ( |  | ) | const

| Return the liquid brush. Definition at line 497 of file qwt_thermo.cpp.

const QColor & QwtThermo::fillColor | ( |  | ) | const

| Return the liquid color. Definition at line 513 of file qwt_thermo.cpp.

void QwtThermo::fontChange | ( | const QFont & | oldFont | ) | `[protected, virtual]`

| Notify a font change. Definition at line 274 of file qwt_thermo.cpp. References layoutThermo().

void QwtThermo::layoutThermo | ( | bool | update_geometry = `TRUE` | ) | `[protected]`

  | Recalculate the QwtThermo geometry and layout based on the QwtThermo::rect() and the fonts. Parameters:
  | update_geometry | notify the layout system and call update to redraw the scale
Definition at line 109 of file qwt_thermo.cpp. References QwtScaleDraw::minBorderDist(), QwtScaleIf::scaleDraw(), QwtScaleDraw::setGeometry(), and QwtDiMap::setIntRange(). Referenced by fontChange(), resizeEvent(), scaleChange(), setBorderWidth(), setOrientation(), setPipeWidth(), and setRange().

double QwtThermo::maxValue | ( |  | ) | const

| Return the maximum value. Definition at line 133 of file qwt_thermo.h.

QSize QwtThermo::minimumSizeHint | ( |  | ) | const`[virtual]`

| Return a minimum size hint. Warning: The return value depends on the font and the scale. See also: QwtThermo::sizeHint Definition at line 652 of file qwt_thermo.cpp. References QwtScaleDraw::minHeight(), QwtScaleDraw::minWidth(), and QwtScaleIf::scaleDraw(). Referenced by sizeHint().

double QwtThermo::minValue | ( |  | ) | const

| Return the minimum value. Definition at line 138 of file qwt_thermo.h.

void QwtThermo::paintEvent | ( | QPaintEvent * | e | ) | `[protected, virtual]`

| Qt paint event. Definition at line 68 of file qwt_thermo.cpp. References draw(), and QwtPaintBuffer::painter().

int QwtThermo::pipeWidth | ( |  | ) | const

| Return the width of the pipe. Definition at line 575 of file qwt_thermo.cpp.

void QwtThermo::resizeEvent | ( | QResizeEvent * | e | ) | `[protected, virtual]`

| Qt resize event handler. Definition at line 98 of file qwt_thermo.cpp. References layoutThermo().

void QwtThermo::scaleChange | ( |  | ) | `[protected, virtual]`

| Notify a scale change. Implements QwtScaleIf. Definition at line 281 of file qwt_thermo.cpp. References layoutThermo(). Referenced by setRange().

QwtThermo::ScalePos QwtThermo::scalePosition | ( |  | ) | const

| Return the scale position. Definition at line 268 of file qwt_thermo.cpp.

void QwtThermo::setAlarmBrush | ( | const QBrush & | b | ) |

  | Specify the liquid brush above the alarm threshold. Parameters:
  | c | New brush. The default is solid white.
Definition at line 522 of file qwt_thermo.cpp.

void QwtThermo::setAlarmColor | ( | const QColor & | c | ) |

  | Specify the liquid color above the alarm threshold. Parameters:
  | c | New color. The default is white.
Definition at line 538 of file qwt_thermo.cpp.

void QwtThermo::setAlarmEnabled | ( | bool | tf | ) |

  | Enable or disable the alarm threshold. Parameters:
  | tf | TRUE (disabled) or FALSE (enabled)
Definition at line 604 of file qwt_thermo.cpp.

void QwtThermo::setAlarmLevel | ( | double | v | ) |

| Specify the alarm threshold. Definition at line 551 of file qwt_thermo.cpp.

void QwtThermo::setBorderWidth | ( | int | w | ) |

| Set the border width of the pipe. Definition at line 446 of file qwt_thermo.cpp. References layoutThermo().

void QwtThermo::setFillBrush | ( | const QBrush & | b | ) |

  | Change the brush of the liquid. Parameters:
  | c | New brush. The default brush is solid black.
Definition at line 490 of file qwt_thermo.cpp.

void QwtThermo::setFillColor | ( | const QColor & | c | ) |

  | Change the color of the liquid. Parameters:
  | c | New color. The default color is black.
Definition at line 506 of file qwt_thermo.cpp.

void QwtThermo::setMargin | ( | int | m | ) |

  | Specify the distance between the pipe's endpoints and the widget's border. The margin is used to leave some space for the scale labels. If a large font is used, it is advisable to adjust the margins. Parameters:
  | m | New Margin. The default values are 10 for horizontal orientation and 20 for vertical orientation.
Warning: The margin has no effect if the scale is disabled. This function is a NOOP because margins are determined automatically. Definition at line 595 of file qwt_thermo.cpp.

void QwtThermo::setMaxValue | ( | double | v | ) |

| Set the maximum value. Definition at line 131 of file qwt_thermo.h.

void QwtThermo::setMinValue | ( | double | v | ) |

| Set the minimum value. Definition at line 136 of file qwt_thermo.h.

void QwtThermo::setOrientation | ( | Qt::Orientation | o,
|  | ScalePos | s
| ) |

  | Set the thermometer orientation and the scale position. The scale position None disables the scale. Parameters:
  | o | orientation. Possible values are Qt::Horizontal and Qt::Vertical. The default value is Qt::Vertical.
  | s | Position of the scale. The default value is None.
A valid combination of scale position and orientation is enforced: a horizontal thermometer can have the scale positions Top, Bottom or None; a vertical thermometer can have the scale positions Left, Right or None; an invalid scale position will default to None. See also: QwtThermo::setScalePosition() Definition at line 220 of file qwt_thermo.cpp. References layoutThermo(). Referenced by setScalePosition().

void QwtThermo::setPipeWidth | ( | int | w | ) |

| Change the width of the pipe. Definition at line 565 of file qwt_thermo.cpp. References layoutThermo().

void QwtThermo::setRange | ( | double | vmin,
|  | double | vmax,
|  | bool | logarithmic = `FALSE`
| ) |

  | Set the range. Parameters:
  | vmin | value corresponding lower or left end of the thermometer
  | vmax | value corresponding to the upper or right end of the thermometer
  | logarithmic | logarithmic mapping, TRUE or FALSE
Definition at line 468 of file qwt_thermo.cpp. References QwtScaleIf::hasUserScale(), layoutThermo(), scaleChange(), QwtScaleDraw::scaleDiv(), QwtScaleIf::scaleDraw(), QwtScaleIf::scaleMaxMajor(), QwtScaleIf::scaleMaxMinor(), QwtDiMap::setDblRange(), and QwtScaleDraw::setScale().

void QwtThermo::setScalePosition | ( | ScalePos | s | ) |

  | Change the scale position (and thermometer orientation). Parameters:
  | s | Position of the scale.
A valid combination of scale position and orientation is enforced: if the new scale position is Left or Right, the scale orientation will become Qt::Vertical; if the new scale position is Bottom or Top, the scale orientation will become Qt::Horizontal; if the new scale position is None, the scale orientation will not change. See also: QwtThermo::setOrientation() Definition at line 257 of file qwt_thermo.cpp. References setOrientation().

void QwtThermo::setValue | ( | double | val | ) | `[slot]`

| Set the current value. Definition at line 58 of file qwt_thermo.cpp.

QSize QwtThermo::sizeHint | ( |  | ) | const`[virtual]`

| Returns: the minimum size hint See also: QwtThermo::minimumSizeHint Definition at line 642 of file qwt_thermo.cpp. References minimumSizeHint().

QSizePolicy QwtThermo::sizePolicy | ( |  | ) | const`[virtual]`

| Returns: Fixed/MinimumExpanding for vertical, MinimumExpanding/Fixed for horizontal thermos. Definition at line 621 of file qwt_thermo.cpp. References QwtScaleDraw::orientation(), and QwtScaleIf::scaleDraw().

double QwtThermo::value | ( |  | ) | const

| Return the value. Definition at line 141 of file qwt_thermo.h.