QtIcoHandler Class Reference

The QtIcoHandler class provides support for the ICO image format. More...

#include <qicohandler.h>

Inheritance diagram for QtIcoHandler:

Public Functions
bool	canRead () const
	Verifies if some values (magic bytes) are set as expected in the header of the file. More...
int	imageCount () const
	Reimplemented Function More...
bool	jumpToImage (int imageNumber)
	Reimplemented Function More...
bool	jumpToNextImage ()
	Reimplemented Function More...
QByteArray	name () const
	Return the common identifier of the format. More...
QVariant	option (ImageOption option) const
	Returns the value assigned to option as a QVariant. More...
	QtIcoHandler (QIODevice *device)
	Constructs an instance of QtIcoHandler initialized to use device. More...
bool	read (QImage *image)
	Reimplemented Function More...
bool	supportsOption (ImageOption option) const
	Returns true if the QImageIOHandler supports the option option; otherwise returns false. More...
bool	write (const QImage &image)
	Reimplemented Function More...
virtual	~QtIcoHandler ()
	Destructor for QtIcoHandler. More...
Public Functions inherited from QImageIOHandler
virtual int	currentImageNumber () const
	For image formats that support animation, this function returns the sequence number of the current image in the animation. More...
virtual QRect	currentImageRect () const
	Returns the rect of the current image. More...
QIODevice *	device () const
	Returns the device currently assigned to the QImageIOHandler. More...
QByteArray	format () const
	Returns the format that is currently assigned to QImageIOHandler. More...
virtual int	loopCount () const
	For image formats that support animation, this function returns the number of times the animation should loop. More...
virtual int	nextImageDelay () const
	For image formats that support animation, this function returns the number of milliseconds to wait until reading the next image. More...
	QImageIOHandler ()
	Constructs a QImageIOHandler object. More...
void	setDevice (QIODevice *device)
	Sets the device of the QImageIOHandler to device. More...
void	setFormat (const QByteArray &format)
	Sets the format of the QImageIOHandler to format. More...
void	setFormat (const QByteArray &format) const
	Sets the format of the QImageIOHandler to format. More...
virtual void	setOption (ImageOption option, const QVariant &value)
	Sets the option option with the value value. More...
virtual	~QImageIOHandler ()
	Destructs the QImageIOHandler object. More...

Static Public Functions
static bool	canRead (QIODevice *device)
	This static function is used by the plugin code, and is provided for convenience only. More...

Properties
int	m_currentIconIndex
ICOReader *	m_pICOReader

Additional Inherited Members
Public Types inherited from QImageIOHandler
enum	ImageOption {   Size, ClipRect, Description, ScaledClipRect,   ScaledSize, CompressionRatio, Gamma, Quality,   Name, SubType, IncrementalReading, Endianness,   Animation, BackgroundColor, ImageFormat }
	This enum describes the different options supported by QImageIOHandler. More...
Protected Functions inherited from QImageIOHandler
	QImageIOHandler (QImageIOHandlerPrivate &dd)
	Constructs a QImageIOHandler object, using the private member dd. More...
Protected Variables inherited from QImageIOHandler
QScopedPointer< QImageIOHandlerPrivate >	d_ptr

Detailed Description

The QtIcoHandler class provides support for the ICO image format.

Since

4.4

Warning

This function is not part of the public interface.

Definition at line 49 of file qicohandler.h.

Constructors and Destructors

QtIcoHandler()

QtIcoHandler::QtIcoHandler

(

QIODevice *

device

)

Constructs an instance of QtIcoHandler initialized to use device.

Definition at line 769 of file qicohandler.cpp.

{
    m_currentIconIndex = 0;
    setDevice(device);
    m_pICOReader = new ICOReader(device);
}

~QtIcoHandler()

QtIcoHandler::~QtIcoHandler ( )

virtual

Destructor for QtIcoHandler.

Definition at line 779 of file qicohandler.cpp.

{
    delete m_pICOReader;
}

Functions

canRead() [1/2]

bool QtIcoHandler::canRead ( ) const

virtual

Verifies if some values (magic bytes) are set as expected in the header of the file.

If the magic bytes were found, it is assumed that the QtIcoHandler can read the file.

Implements QImageIOHandler.

Definition at line 812 of file qicohandler.cpp.

Referenced by QICOPlugin::capabilities().

{
    bool bCanRead = false;
    QIODevice *device = QImageIOHandler::device();
    if (device) {
        bCanRead = ICOReader::canRead(device);
        if (bCanRead)
            setFormat("ico");
    } else {
        qWarning("QtIcoHandler::canRead() called with no device");
    }
    return bCanRead;
}

canRead() [2/2]

bool QtIcoHandler::canRead ( QIODevice *  device )

static

This static function is used by the plugin code, and is provided for convenience only.

device must be an opened device with pointing to the start of the header data of the ICO file.

Definition at line 829 of file qicohandler.cpp.

{
    Q_ASSERT(device);
    return ICOReader::canRead(device);
}

imageCount()

int QtIcoHandler::imageCount ( ) const

virtual

Reimplemented Function

Reimplemented from QImageIOHandler.

Definition at line 877 of file qicohandler.cpp.

{
    return m_pICOReader->count();
}

jumpToImage()

bool QtIcoHandler::jumpToImage ( int  imageNumber )

virtual

Reimplemented Function

Reimplemented from QImageIOHandler.

Definition at line 885 of file qicohandler.cpp.

{
    if (imageNumber < imageCount()) {
        m_currentIconIndex = imageNumber;
    }

    return (imageNumber < imageCount()) ? true : false;
}

jumpToNextImage()

bool QtIcoHandler::jumpToNextImage ( )

virtual

Reimplemented Function

Reimplemented from QImageIOHandler.

Definition at line 897 of file qicohandler.cpp.

{
    return jumpToImage(m_currentIconIndex + 1);
}

name()

QByteArray QtIcoHandler::name ( ) const

virtual

Return the common identifier of the format.

For ICO format this will return "ico".

Reimplemented from QImageIOHandler.

Definition at line 868 of file qicohandler.cpp.

{
    return "ico";
}

option()

QVariant QtIcoHandler::option ( ImageOption  option ) const

virtual

Returns the value assigned to option as a QVariant.

The type of the value depends on the option. For example, option(Size) returns a QSize variant.

See also

setOption(), supportsOption()

Reimplemented from QImageIOHandler.

Definition at line 784 of file qicohandler.cpp.

{
    if (option == Size) {
        QIODevice *device = QImageIOHandler::device();
        qint64 oldPos = device->pos();
        ICONDIRENTRY iconEntry;
        if (device->seek(oldPos + ICONDIR_SIZE + (m_currentIconIndex * ICONDIRENTRY_SIZE))) {
            if (readIconDirEntry(device, &iconEntry)) {
                device->seek(oldPos);
                return QSize(iconEntry.bWidth, iconEntry.bHeight);
            }
        }
        if (!device->isSequential())
            device->seek(oldPos);
    }
    return QVariant();
}

read()

bool QtIcoHandler::read ( QImage *  image )

virtual

Reimplemented Function

Implements QImageIOHandler.

Definition at line 838 of file qicohandler.cpp.

{
    bool bSuccess = false;
    QImage img = m_pICOReader->iconAt(m_currentIconIndex);

    // Make sure we only write to \a image when we succeed.
    if (!img.isNull()) {
        bSuccess = true;
        *image = img;
    }

    return bSuccess;
}

supportsOption()

bool QtIcoHandler::supportsOption ( ImageOption  option ) const

virtual

Returns true if the QImageIOHandler supports the option option; otherwise returns false.

For example, if the QImageIOHandler supports the Size option, supportsOption(Size) must return true.

See also

setOption(), option()

Reimplemented from QImageIOHandler.

Definition at line 802 of file qicohandler.cpp.

{
    return option == Size;
}

write()

bool QtIcoHandler::write ( const QImage &  image )

virtual

Reimplemented Function

Reimplemented from QImageIOHandler.

Definition at line 856 of file qicohandler.cpp.

{
    QIODevice *device = QImageIOHandler::device();
    QList<QImage> imgs;
    imgs.append(image);
    return ICOReader::write(device, imgs);
}

Properties

m_currentIconIndex

int QtIcoHandler::m_currentIconIndex

private

Definition at line 71 of file qicohandler.h.

m_pICOReader

ICOReader* QtIcoHandler::m_pICOReader

private

Definition at line 72 of file qicohandler.h.

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The documentation for this class was generated from the following files:

• /src/plugins/imageformats/ico/qicohandler.h
• /src/plugins/imageformats/ico/qicohandler.cpp