qimageiohandler.h

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#ifndef QIMAGEIOHANDLER_H
#define QIMAGEIOHANDLER_H

#include <QtCore/qplugin.h>
#include <QtCore/qfactoryinterface.h>
#include <QtCore/qscopedpointer.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Gui)

class QImage;
class QRect;
class QSize;
class QVariant;

class QImageIOHandlerPrivate;
class Q_GUI_EXPORT QImageIOHandler
{
    Q_DECLARE_PRIVATE(QImageIOHandler)
public:
    QImageIOHandler();
    virtual ~QImageIOHandler();

    void setDevice(QIODevice *device);
    QIODevice *device() const;

    void setFormat(const QByteArray &format);
    void setFormat(const QByteArray &format) const;
    QByteArray format() const;

    virtual QByteArray name() const;

    virtual bool canRead() const = 0;
    virtual bool read(QImage *image) = 0;
    virtual bool write(const QImage &image);

    enum ImageOption {
        Size,
        ClipRect,
        Description,
        ScaledClipRect,
        ScaledSize,
        CompressionRatio,
        Gamma,
        Quality,
        Name,
        SubType,
        IncrementalReading,
        Endianness,
        Animation,
        BackgroundColor,
        ImageFormat
    };
    virtual QVariant option(ImageOption option) const;
    virtual void setOption(ImageOption option, const QVariant &value);
    virtual bool supportsOption(ImageOption option) const;

    // incremental loading
    virtual bool jumpToNextImage();
    virtual bool jumpToImage(int imageNumber);
    virtual int loopCount() const;
    virtual int imageCount() const;
    virtual int nextImageDelay() const;
    virtual int currentImageNumber() const;
    virtual QRect currentImageRect() const;

protected:
    QImageIOHandler(QImageIOHandlerPrivate &dd);
    QScopedPointer<QImageIOHandlerPrivate> d_ptr;
private:
    Q_DISABLE_COPY(QImageIOHandler)
};

struct Q_GUI_EXPORT QImageIOHandlerFactoryInterface : public QFactoryInterface
{
    virtual QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const = 0;
};

#define QImageIOHandlerFactoryInterface_iid "com.trolltech.Qt.QImageIOHandlerFactoryInterface"
Q_DECLARE_INTERFACE(QImageIOHandlerFactoryInterface, QImageIOHandlerFactoryInterface_iid)

class Q_GUI_EXPORT QImageIOPlugin : public QObject, public QImageIOHandlerFactoryInterface
{
    Q_OBJECT
    Q_INTERFACES(QImageIOHandlerFactoryInterface:QFactoryInterface)
public:
    explicit QImageIOPlugin(QObject *parent = 0);
    virtual ~QImageIOPlugin();

    enum Capability {
        CanRead = 0x1,
        CanWrite = 0x2,
        CanReadIncremental = 0x4
    };
    Q_DECLARE_FLAGS(Capabilities, Capability)

    virtual Capabilities capabilities(QIODevice *device, const QByteArray &format) const = 0;
    virtual QStringList keys() const = 0;
    virtual QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const = 0;
};

Q_DECLARE_OPERATORS_FOR_FLAGS(QImageIOPlugin::Capabilities)

QT_END_NAMESPACE

QT_END_HEADER

#endif // QIMAGEIOHANDLER_H