Qt 4.8: QGraphicsDropShadowEffect Class Reference

Qt Reference Documentation

# QGraphicsDropShadowEffect Class Reference

The QGraphicsDropShadowEffect class provides a drop shadow effect. More...

     #include <QGraphicsDropShadowEffect>

Inherits: QGraphicsEffect.

This class was introduced in Qt 4.6.

- List of all members, including inherited members

## Properties

blurRadius : qreal color : QColor offset : QPointF | xOffset : qreal yOffset : qreal

- 1 property inherited from QGraphicsEffect
- 1 property inherited from QObject

## Public Functions

| QGraphicsDropShadowEffect ( QObject * parent = 0 )
| ~QGraphicsDropShadowEffect ()
qreal | blurRadius () const
QColor | color () const
QPointF | offset () const
qreal | xOffset () const
qreal | yOffset () const

## Reimplemented Public Functions

virtual QRectF | boundingRectFor ( const QRectF & rect ) const

- 3 public functions inherited from QGraphicsEffect
- 29 public functions inherited from QObject

## Public Slots

void | setBlurRadius ( qreal blurRadius )
void | setColor ( const QColor & color )
void | setOffset ( const QPointF & ofs )
void | setOffset ( qreal dx, qreal dy )
void | setOffset ( qreal d )
void | setXOffset ( qreal dx )
void | setYOffset ( qreal dy )

- 2 public slots inherited from QGraphicsEffect
- 1 public slot inherited from QObject

## Signals

void | blurRadiusChanged ( qreal blurRadius )
void | colorChanged ( const QColor & color )
void | offsetChanged ( const QPointF & offset )

- 1 signal inherited from QGraphicsEffect
- 1 signal inherited from QObject

## Reimplemented Protected Functions

virtual void | draw ( QPainter * painter )

- 7 protected functions inherited from QGraphicsEffect
- 8 protected functions inherited from QObject

### Additional Inherited Members

- 7 static public members inherited from QObject
- 7 protected functions inherited from QGraphicsEffect
- 8 protected functions inherited from QObject

## Detailed Description

The QGraphicsDropShadowEffect class provides a drop shadow effect.

A drop shadow effect renders the source with a drop shadow. The color of the drop shadow can be modified using the setColor() function. The drop shadow offset can be modified using the setOffset() function and the blur radius of the drop shadow can be changed with the setBlurRadius() function.

By default, the drop shadow is a semi-transparent dark gray (QColor(63, 63, 63, 180)) shadow, blurred with a radius of 1 at an offset of 8 pixels towards the lower right. The drop shadow offset is specified in device coordinates.

See also QGraphicsBlurEffect, QGraphicsColorizeEffect, and QGraphicsOpacityEffect.

## Property Documentation

### blurRadius : qreal

This property holds the blur radius in pixels of the drop shadow.

Using a smaller radius results in a sharper shadow, whereas using a bigger radius results in a more blurred shadow.

By default, the blur radius is 1 pixel.

Access functions:

qreal | blurRadius () const
void | setBlurRadius ( qreal blurRadius )

Notifier signal:

void | blurRadiusChanged ( qreal blurRadius )

See also color(), offset(), and ..

### color : QColor

This property holds the color of the drop shadow.

By default, the drop color is a semi-transparent dark gray (QColor(63, 63, 63, 180)).

Access functions:

QColor | color () const
void | setColor ( const QColor & color )

Notifier signal:

void | colorChanged ( const QColor & color )

See also offset() and blurRadius().

### offset : QPointF

This property holds the shadow offset in pixels.

By default, the offset is 8 pixels towards the lower right.

The offset is given in device coordinates, which means it is unaffected by scale.

Access functions:

QPointF | offset () const
void | setOffset ( const QPointF & ofs )
void | setOffset ( qreal dx, qreal dy )
void | setOffset ( qreal d )

Notifier signal:

void | offsetChanged ( const QPointF & offset )

See also xOffset(), yOffset(), blurRadius(), and color().

### xOffset : qreal

This property holds the horizontal shadow offset in pixels.

By default, the horizontal shadow offset is 8 pixels.

Access functions:

qreal | xOffset () const
void | setXOffset ( qreal dx )

Notifier signal:

void | offsetChanged ( const QPointF & offset )

See also yOffset() and offset().

### yOffset : qreal

This property holds the vertical shadow offset in pixels.

By default, the vertical shadow offset is 8 pixels.

Access functions:

qreal | yOffset () const
void | setYOffset ( qreal dy )

Notifier signal:

void | offsetChanged ( const QPointF & offset )

See also xOffset() and offset().

## Member Function Documentation

### QGraphicsDropShadowEffect::QGraphicsDropShadowEffect ( QObject * parent = 0 )

Constructs a new QGraphicsDropShadowEffect instance. The parent parameter is passed to QGraphicsEffect's constructor.

### QGraphicsDropShadowEffect::~QGraphicsDropShadowEffect ()

Destroys the effect.

### void QGraphicsDropShadowEffect::blurRadiusChanged ( qreal blurRadius )`[signal]`

This signal is emitted whenever the effect's blur radius changes. The blurRadius parameter holds the effect's new blur radius.

### QRectF QGraphicsDropShadowEffect::boundingRectFor ( const QRectF & rect ) const`[virtual]`

Reimplemented from QGraphicsEffect::boundingRectFor().

### void QGraphicsDropShadowEffect::colorChanged ( const QColor & color )`[signal]`

This signal is emitted whenever the effect's color changes. The color parameter holds the effect's new color.

### void QGraphicsDropShadowEffect::draw ( QPainter * painter )`[virtual protected]`

Reimplemented from QGraphicsEffect::draw().

### void QGraphicsDropShadowEffect::offsetChanged ( const QPointF & offset )`[signal]`

This signal is emitted whenever the effect's shadow offset changes. The offset parameter holds the effect's new shadow offset.