// -*- c++ -*- /* This file is part of the KDE libraries SPDX-FileCopyrightText: 2000 David Faure SPDX-FileCopyrightText: 2000 Carsten Pfeiffer SPDX-FileCopyrightText: 2001 Malte Starostik SPDX-License-Identifier: LGPL-2.0-or-later */ #ifndef KIO_PREVIEWJOB_H #define KIO_PREVIEWJOB_H #include "kiogui_export.h" #include #include class QPixmap; class KPluginMetaData; namespace KIO { class PreviewJobPrivate; /*! * \class KIO::PreviewJob * \inmodule KIOGui * \inheaderfile KIO/PreviewJob * * This class catches a preview (thumbnail) for files. * * \brief KIO Job to get a thumbnail picture. */ class KIOGUI_EXPORT PreviewJob : public KIO::Job { Q_OBJECT public: /*! * Specifies the type of scaling that is applied to the generated preview. * For HiDPI, pixel density scaling, see setDevicePixelRatio * * \value Unscaled The original size of the preview will be returned. Most previews will return a size of 256 x 256 pixels. * \value Scaled The preview will be scaled to the size specified when constructing the PreviewJob. The aspect ratio will be kept. * \value ScaledAndCached The preview will be scaled to the size specified when constructing the PreviewJob. The result will be cached for later use. Per * default ScaledAndCached is set. */ enum ScaleType { Unscaled, Scaled, ScaledAndCached, }; /*! * \a items List of files to create previews for. * \a size Desired size of the preview. * \a enabledPlugins If non-zero it defines the list of plugins that * are considered for generating the preview. If * enabledPlugins is zero the plugins specified in the * KConfigGroup "PreviewSettings" are used. */ PreviewJob(const KFileItemList &items, const QSize &size, const QStringList *enabledPlugins = nullptr); ~PreviewJob() override; /*! * Sets the scale type for the generated preview. Per default * PreviewJob::ScaledAndCached is set. * \sa PreviewJob::ScaleType */ void setScaleType(ScaleType type); /*! * Returns The scale type for the generated preview. * \sa PreviewJob::ScaleType */ ScaleType scaleType() const; #if KIOGUI_ENABLE_DEPRECATED_SINCE(6, 22) /*! * Removes an item from preview processing. Use this if you passed * an item to filePreview and want to delete it now. * * \a url the url of the item that should be removed from the preview queue * \deprecated[6.22] Unused. */ KIOGUI_DEPRECATED_VERSION(6, 22, "Unused.") void removeItem(const QUrl &url); #endif /*! * If \a ignoreSize is true, then the preview is always * generated regardless of the settings **/ void setIgnoreMaximumSize(bool ignoreSize = true); /*! * Sets the sequence \a index given to the thumb creators. * Use the sequence index, it is possible to create alternative * icons for the same item. For example it may allow iterating through * the items of a directory, or the frames of a video. * **/ void setSequenceIndex(int index); /*! * Returns the currently set sequence index * **/ int sequenceIndex() const; /*! * Returns the index at which the thumbs of a ThumbSequenceCreator start * wrapping around ("looping"). Fractional values may be returned if the * ThumbSequenceCreator supports sub-integer precision, but frontends * supporting only integer sequence indices may choose to round it down. * * \since 5.80 */ float sequenceIndexWraparoundPoint() const; /*! * Determines whether the ThumbCreator in use is a ThumbSequenceCreator. * * \since 5.80 */ bool handlesSequences() const; /*! * Request preview to use the device pixel ratio \a dpr. * The returned thumbnail may not respect the device pixel ratio requested. * Use QPixmap::devicePixelRatio to check, or paint as necessary. * * \since 5.84 */ void setDevicePixelRatio(qreal dpr); /*! * Returns a list of all available preview plugins. The list * contains the basenames of the plugins' .desktop files (no path, * no .desktop). * Returns the list of all available plugins */ static QStringList availablePlugins(); /*! * Returns all plugins that are considered when a preview is generated * The result is internally cached, meaning any further method call will not reload the plugins * \since 5.90 */ static QList availableThumbnailerPlugins(); /*! * Returns a list of plugins that should be enabled by default, which is all plugins * Minus the plugins specified in an internal blacklist * Returns the list of plugins that should be enabled by default * \since 5.40 */ static QStringList defaultPlugins(); /*! * Returns a list of all supported MIME types. The list can * contain entries like text/ * (without the space). * Returns the list of MIME types */ static QStringList supportedMimeTypes(); Q_SIGNALS: /*! * Emitted when a thumbnail picture for \a item has been successfully * retrieved. * * \a item the file of the preview * * \a preview the preview image * * \note If you need a preview as a QImage object, use the generated() signal. * \sa generated() */ void gotPreview(const KFileItem &item, const QPixmap &preview); /*! * Emitted when a thumbnail for \a item could not be created, * either because a ThumbCreator for its MIME type does not * exist, or because something went wrong. * * \a item the file that failed */ void failed(const KFileItem &item); /*! * Emitted when a \a preview for \a item has been successfully generated. * * \since 6.15 */ void generated(const KFileItem &item, const QImage &preview); protected Q_SLOTS: void slotResult(KJob *job) override; protected: bool doKill() override; private: friend class PreviewJobPrivate; KIOGUI_NO_EXPORT void emitPreview(const KFileItem &item, const QImage &previewImage); Q_DECLARE_PRIVATE(PreviewJob) public: /*! * Sets a default device Pixel Ratio used for Previews * \sa setDevicePixelRatio * * Defaults to 1 * * \since 5.84 */ static void setDefaultDevicePixelRatio(qreal devicePixelRatio); }; /*! * \relates KIO::PreviewJob * * Creates a PreviewJob to generate a preview image for the given items. * * \a items List of files to create previews for. * * \a size Desired size of the preview. * * \a enabledPlugins If non-zero it defines the list of plugins that * are considered for generating the preview. If * enabledPlugins is zero the plugins specified in the * KConfigGroup "PreviewSettings" are used. */ KIOGUI_EXPORT PreviewJob *filePreview(const KFileItemList &items, const QSize &size, const QStringList *enabledPlugins = nullptr); } #endif