com.trolltech.qt.gui
Class QIcon

java.lang.Object
  extended by com.trolltech.qt.internal.QSignalEmitterInternal
      extended by com.trolltech.qt.QSignalEmitter
          extended by com.trolltech.qt.QtJambiObject
              extended by com.trolltech.qt.gui.QIcon
All Implemented Interfaces:
QtJambiInterface, java.lang.Cloneable

public class QIcon
extends QtJambiObject
implements java.lang.Cloneable

The QIcon class provides scalable icons in different modes and states. A QIcon can generate smaller, larger, active, and disabled pixmaps from the set of pixmaps it is given. Such pixmaps are used by Qt widgets to show an icon representing a particular action.

The simplest use of QIcon is to create one from a QPixmap file or resource, and then use it, allowing Qt to work out all the required icon styles and sizes. For example:

        QToolButton button = new QToolButton();
        button.setIcon(new QIcon("open.xpm"));
To undo a QIcon, simply set a null icon in its place:
        button.setIcon(null);
Use the QImageReader::supportedImageFormats() and QImageWriter::supportedImageFormats() functions to retrieve a complete list of the supported file formats.

When you retrieve a pixmap using pixmap(QSize, Mode, State), and no pixmap for this given size, mode and state has been added with addFile() or addPixmap(), then QIcon will generate one on the fly. This pixmap generation happens in a QIconEngineV2. The default engine scales pixmaps down if required, but never up, and it uses the current style to calculate a disabled appearance. By using custom icon engines, you can customize every aspect of generated icons. With QIconEnginePluginV2 it is possible to register different icon engines for different file suffixes, making it possible for third parties to provide additional icon engines to those included with Qt.

Note: Since Qt 4.2, an icon engine that supports SVG is included.

Making Classes that Use QIcon

If you write your own widgets that have an option to set a small pixmap, consider allowing a QIcon to be set for that pixmap. The Qt class QToolButton is an example of such a widget.

Provide a method to set a QIcon, and when you draw the icon, choose whichever pixmap is appropriate for the current state of your widget. For example:

    void drawIcon(QPainter ainter, QPoint pos)
    {
        QPixmap pixmap = icon.pixmap(new QSize(22, 22),
                                     isEnabled() ? QIcon.Mode.Normal : QIcon.Mode.Disabled,
                                     isOn() ? QIcon.State.On : QIcon.State.Off);
        painter.drawPixmap(pos, pixmap);
    }
You might also make use of the Active mode, perhaps making your widget Active when the mouse is over the widget (see QWidget::enterEvent()), while the mouse is pressed pending the release that will activate the function, or when it is the currently selected item. If the widget can be toggled, the "On" mode might be used to draw a different icon.

See also:
GUI Design Handbook: Iconic Label, and Icons Example.


Nested Class Summary
static class QIcon.Mode
          This enum type describes the mode for which a pixmap is intended to be used.
static class QIcon.State
          This enum describes the state for which a pixmap is intended to be used.
 
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.AbstractSignal, QSignalEmitter.PrivateSignal0, QSignalEmitter.PrivateSignal1, QSignalEmitter.PrivateSignal2, QSignalEmitter.PrivateSignal3, QSignalEmitter.PrivateSignal4, QSignalEmitter.PrivateSignal5, QSignalEmitter.PrivateSignal6, QSignalEmitter.PrivateSignal7, QSignalEmitter.PrivateSignal8, QSignalEmitter.PrivateSignal9, QSignalEmitter.Signal0, QSignalEmitter.Signal1, QSignalEmitter.Signal2, QSignalEmitter.Signal3, QSignalEmitter.Signal4, QSignalEmitter.Signal5, QSignalEmitter.Signal6, QSignalEmitter.Signal7, QSignalEmitter.Signal8, QSignalEmitter.Signal9
 
Nested classes/interfaces inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
com.trolltech.qt.internal.QSignalEmitterInternal.AbstractSignalInternal
 
Field Summary
 
Fields inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
currentSender
 
Constructor Summary
QIcon()
          Constructs a null icon.
QIcon(QIcon other)
          Constructs a copy of other.
QIcon(QIconEngine engine)
          Creates an icon with a specific icon engine.
QIcon(QIconEngineV2 engine)
          Creates an icon with a specific icon engine.
QIcon(QPixmap pixmap)
          Constructs an icon from a pixmap.
QIcon(java.lang.String fileName)
          Constructs an icon from the file with the given fileName.
 
Method Summary
 QSize actualSize(QSize size)
          Returns the actual size of the icon for the requested size, mode, and state.
 QSize actualSize(QSize size, QIcon.Mode mode)
          Returns the actual size of the icon for the requested size, mode, and state.
 QSize actualSize(QSize size, QIcon.Mode mode, QIcon.State state)
          Returns the actual size of the icon for the requested size, mode, and state.
 void addFile(java.lang.String fileName)
          Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state.
 void addFile(java.lang.String fileName, QSize size)
          Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state.
 void addFile(java.lang.String fileName, QSize size, QIcon.Mode mode)
          Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state.
 void addFile(java.lang.String fileName, QSize size, QIcon.Mode mode, QIcon.State state)
          Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state.
 void addPixmap(QPixmap pixmap)
          Adds pixmap to the icon, as a specialization for mode and state.
 void addPixmap(QPixmap pixmap, QIcon.Mode mode)
          Adds pixmap to the icon, as a specialization for mode and state.
 void addPixmap(QPixmap pixmap, QIcon.Mode mode, QIcon.State state)
          Adds pixmap to the icon, as a specialization for mode and state.
 java.util.List availableSizes()
          Returns a list of available icon sizes for the specified mode and state.
 java.util.List availableSizes(QIcon.Mode mode)
          Returns a list of available icon sizes for the specified mode and state.
 java.util.List availableSizes(QIcon.Mode mode, QIcon.State state)
          Returns a list of available icon sizes for the specified mode and state.
 long cacheKey()
          Returns a number that identifies the contents of this QIcon object.
 QIcon clone()
          This method is reimplemented for internal reasons
 boolean isNull()
          Returns true if the icon is empty; otherwise returns false.
 void paint(QPainter painter, int x, int y, int w, int h)
          This is an overloaded member function, provided for convenience.
 void paint(QPainter painter, int x, int y, int w, int h, Qt.Alignment alignment)
          This is an overloaded member function, provided for convenience.
 void paint(QPainter painter, int x, int y, int w, int h, Qt.Alignment alignment, QIcon.Mode mode)
          This is an overloaded member function, provided for convenience.
 void paint(QPainter painter, int x, int y, int w, int h, Qt.Alignment alignment, QIcon.Mode mode, QIcon.State state)
          This is an overloaded member function, provided for convenience.
 void paint(QPainter painter, QRect rect)
          Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.
 void paint(QPainter painter, QRect rect, Qt.Alignment alignment)
          Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.
 void paint(QPainter painter, QRect rect, Qt.Alignment alignment, QIcon.Mode mode)
          Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.
 void paint(QPainter painter, QRect rect, Qt.Alignment alignment, QIcon.Mode mode, QIcon.State state)
          Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.
 QPixmap pixmap(int extent)
          This is an overloaded member function, provided for convenience.
 QPixmap pixmap(int w, int h)
          This is an overloaded member function, provided for convenience.
 QPixmap pixmap(int w, int h, QIcon.Mode mode)
          This is an overloaded member function, provided for convenience.
 QPixmap pixmap(int w, int h, QIcon.Mode mode, QIcon.State state)
          This is an overloaded member function, provided for convenience.
 QPixmap pixmap(int extent, QIcon.Mode mode)
          This is an overloaded member function, provided for convenience.
 QPixmap pixmap(int extent, QIcon.Mode mode, QIcon.State state)
          This is an overloaded member function, provided for convenience.
 QPixmap pixmap(QSize size)
          Returns a pixmap with the requested size, mode, and state, generating one if necessary.
 QPixmap pixmap(QSize size, QIcon.Mode mode)
          Returns a pixmap with the requested size, mode, and state, generating one if necessary.
 QPixmap pixmap(QSize size, QIcon.Mode mode, QIcon.State state)
          Returns a pixmap with the requested size, mode, and state, generating one if necessary.
 void readFrom(QDataStream arg__1)
          Reads a QIcon
 void writeTo(QDataStream arg__1)
          Writes thisQIcon
 
Methods inherited from class com.trolltech.qt.QtJambiObject
dispose, disposed, equals, finalize, reassignNativeResources, tr, tr, tr
 
Methods inherited from class com.trolltech.qt.QSignalEmitter
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread
 
Methods inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
__qt_signalInitialization
 
Methods inherited from class java.lang.Object
getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface com.trolltech.qt.QtJambiInterface
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership
 

Constructor Detail

QIcon

public QIcon()
Constructs a null icon.


QIcon

public QIcon(QIconEngine engine)
Creates an icon with a specific icon engine. The icon takes ownership of the engine.


QIcon

public QIcon(QIconEngineV2 engine)
Creates an icon with a specific icon engine. The icon takes ownership of the engine.


QIcon

public QIcon(QIcon other)
Constructs a copy of other. This is very fast.


QIcon

public QIcon(QPixmap pixmap)
Constructs an icon from a pixmap.


QIcon

public QIcon(java.lang.String fileName)
Constructs an icon from the file with the given fileName. The file will be loaded on demand.

If fileName contains a relative path (e.g. the filename only) the relevant file must be found relative to the runtime working directory.

The file name can be either refer to an actual file on disk or to one of the application's embedded resources. See the Resource System overview for details on how to embed images and other resource files in the application's executable.

Use the QImageReader::supportedImageFormats() and QImageWriter::supportedImageFormats() functions to retrieve a complete list of the supported file formats.

Method Detail

actualSize

public final QSize actualSize(QSize size,
                              QIcon.Mode mode)
Returns the actual size of the icon for the requested size, mode, and state. The result might be smaller than requested, but never larger.

See also:
pixmap(), and paint().


actualSize

public final QSize actualSize(QSize size)
Returns the actual size of the icon for the requested size, mode, and state. The result might be smaller than requested, but never larger.

See also:
pixmap(), and paint().


actualSize

public final QSize actualSize(QSize size,
                              QIcon.Mode mode,
                              QIcon.State state)
Returns the actual size of the icon for the requested size, mode, and state. The result might be smaller than requested, but never larger.

See also:
pixmap(), and paint().


addFile

public final void addFile(java.lang.String fileName,
                          QSize size,
                          QIcon.Mode mode)
Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state. The file will be loaded on demand. Note: custom icon engines are free to ignore additionally added pixmaps.

If fileName contains a relative path (e.g. the filename only) the relevant file must be found relative to the runtime working directory.

The file name can be either refer to an actual file on disk or to one of the application's embedded resources. See the Resource System overview for details on how to embed images and other resource files in the application's executable.

Use the QImageReader::supportedImageFormats() and QImageWriter::supportedImageFormats() functions to retrieve a complete list of the supported file formats.

See also:
addPixmap().


addFile

public final void addFile(java.lang.String fileName,
                          QSize size)
Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state. The file will be loaded on demand. Note: custom icon engines are free to ignore additionally added pixmaps.

If fileName contains a relative path (e.g. the filename only) the relevant file must be found relative to the runtime working directory.

The file name can be either refer to an actual file on disk or to one of the application's embedded resources. See the Resource System overview for details on how to embed images and other resource files in the application's executable.

Use the QImageReader::supportedImageFormats() and QImageWriter::supportedImageFormats() functions to retrieve a complete list of the supported file formats.

See also:
addPixmap().


addFile

public final void addFile(java.lang.String fileName)
Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state. The file will be loaded on demand. Note: custom icon engines are free to ignore additionally added pixmaps.

If fileName contains a relative path (e.g. the filename only) the relevant file must be found relative to the runtime working directory.

The file name can be either refer to an actual file on disk or to one of the application's embedded resources. See the Resource System overview for details on how to embed images and other resource files in the application's executable.

Use the QImageReader::supportedImageFormats() and QImageWriter::supportedImageFormats() functions to retrieve a complete list of the supported file formats.

See also:
addPixmap().


addFile

public final void addFile(java.lang.String fileName,
                          QSize size,
                          QIcon.Mode mode,
                          QIcon.State state)
Adds an image from the file with the given fileName to the icon, as a specialization for size, mode and state. The file will be loaded on demand. Note: custom icon engines are free to ignore additionally added pixmaps.

If fileName contains a relative path (e.g. the filename only) the relevant file must be found relative to the runtime working directory.

The file name can be either refer to an actual file on disk or to one of the application's embedded resources. See the Resource System overview for details on how to embed images and other resource files in the application's executable.

Use the QImageReader::supportedImageFormats() and QImageWriter::supportedImageFormats() functions to retrieve a complete list of the supported file formats.

See also:
addPixmap().


addPixmap

public final void addPixmap(QPixmap pixmap,
                            QIcon.Mode mode)
Adds pixmap to the icon, as a specialization for mode and state.

Custom icon engines are free to ignore additionally added pixmaps.

See also:
addFile().


addPixmap

public final void addPixmap(QPixmap pixmap)
Adds pixmap to the icon, as a specialization for mode and state.

Custom icon engines are free to ignore additionally added pixmaps.

See also:
addFile().


addPixmap

public final void addPixmap(QPixmap pixmap,
                            QIcon.Mode mode,
                            QIcon.State state)
Adds pixmap to the icon, as a specialization for mode and state.

Custom icon engines are free to ignore additionally added pixmaps.

See also:
addFile().


availableSizes

public final java.util.List availableSizes(QIcon.Mode mode)
Returns a list of available icon sizes for the specified mode and state.


availableSizes

public final java.util.List availableSizes()
Returns a list of available icon sizes for the specified mode and state.


availableSizes

public final java.util.List availableSizes(QIcon.Mode mode,
                                           QIcon.State state)
Returns a list of available icon sizes for the specified mode and state.


cacheKey

public final long cacheKey()
Returns a number that identifies the contents of this QIcon object. Distinct QIcon objects can have the same key if they refer to the same contents.

The cacheKey() will change when the icon is altered via addPixmap() or addFile().

Cache keys are mostly useful in conjunction with caching.

See also:
QPixmap::cacheKey().


isNull

public final boolean isNull()
Returns true if the icon is empty; otherwise returns false.

An icon is empty if it has neither a pixmap nor a filename.

Note: Even a non-null icon might not be able to create valid pixmaps, eg. if the file does not exist or cannot be read.


writeTo

public final void writeTo(QDataStream arg__1)
Writes thisQIcon


readFrom

public final void readFrom(QDataStream arg__1)
Reads a QIcon


paint

public final void paint(QPainter painter,
                        QRect rect,
                        Qt.Alignment alignment,
                        QIcon.Mode mode)
Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.

See also:
actualSize(), and pixmap().


paint

public final void paint(QPainter painter,
                        QRect rect,
                        Qt.Alignment alignment)
Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.

See also:
actualSize(), and pixmap().


paint

public final void paint(QPainter painter,
                        QRect rect)
Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.

See also:
actualSize(), and pixmap().


paint

public final void paint(QPainter painter,
                        QRect rect,
                        Qt.Alignment alignment,
                        QIcon.Mode mode,
                        QIcon.State state)
Uses the painter to paint the icon with specified alignment, required mode, and state into the rectangle rect.

See also:
actualSize(), and pixmap().


paint

public final void paint(QPainter painter,
                        int x,
                        int y,
                        int w,
                        int h,
                        Qt.Alignment alignment,
                        QIcon.Mode mode)
This is an overloaded member function, provided for convenience.

Paints the icon into the rectangle QRect(x, y, w, h).


paint

public final void paint(QPainter painter,
                        int x,
                        int y,
                        int w,
                        int h,
                        Qt.Alignment alignment)
This is an overloaded member function, provided for convenience.

Paints the icon into the rectangle QRect(x, y, w, h).


paint

public final void paint(QPainter painter,
                        int x,
                        int y,
                        int w,
                        int h)
This is an overloaded member function, provided for convenience.

Paints the icon into the rectangle QRect(x, y, w, h).


paint

public final void paint(QPainter painter,
                        int x,
                        int y,
                        int w,
                        int h,
                        Qt.Alignment alignment,
                        QIcon.Mode mode,
                        QIcon.State state)
This is an overloaded member function, provided for convenience.

Paints the icon into the rectangle QRect(x, y, w, h).


pixmap

public final QPixmap pixmap(QSize size,
                            QIcon.Mode mode)
Returns a pixmap with the requested size, mode, and state, generating one if necessary. The pixmap might be smaller than requested, but never larger.

See also:
setPixmap(), actualSize(), and paint().


pixmap

public final QPixmap pixmap(QSize size)
Returns a pixmap with the requested size, mode, and state, generating one if necessary. The pixmap might be smaller than requested, but never larger.

See also:
setPixmap(), actualSize(), and paint().


pixmap

public final QPixmap pixmap(QSize size,
                            QIcon.Mode mode,
                            QIcon.State state)
Returns a pixmap with the requested size, mode, and state, generating one if necessary. The pixmap might be smaller than requested, but never larger.

See also:
setPixmap(), actualSize(), and paint().


pixmap

public final QPixmap pixmap(int extent,
                            QIcon.Mode mode)
This is an overloaded member function, provided for convenience.

Returns a pixmap of size QSize(extent, extent). The pixmap might be smaller than requested, but never larger.


pixmap

public final QPixmap pixmap(int extent)
This is an overloaded member function, provided for convenience.

Returns a pixmap of size QSize(extent, extent). The pixmap might be smaller than requested, but never larger.


pixmap

public final QPixmap pixmap(int extent,
                            QIcon.Mode mode,
                            QIcon.State state)
This is an overloaded member function, provided for convenience.

Returns a pixmap of size QSize(extent, extent). The pixmap might be smaller than requested, but never larger.


pixmap

public final QPixmap pixmap(int w,
                            int h,
                            QIcon.Mode mode)
This is an overloaded member function, provided for convenience.

Returns a pixmap of size QSize(w, h). The pixmap might be smaller than requested, but never larger.


pixmap

public final QPixmap pixmap(int w,
                            int h)
This is an overloaded member function, provided for convenience.

Returns a pixmap of size QSize(w, h). The pixmap might be smaller than requested, but never larger.


pixmap

public final QPixmap pixmap(int w,
                            int h,
                            QIcon.Mode mode,
                            QIcon.State state)
This is an overloaded member function, provided for convenience.

Returns a pixmap of size QSize(w, h). The pixmap might be smaller than requested, but never larger.


clone

public QIcon clone()
This method is reimplemented for internal reasons

Overrides:
clone in class java.lang.Object