Provide a KMetaDataModel for KMetaDataWidget.

This allows to extend the model with custom meta data (might e. g. be useful for Gwenview).

svn path=/trunk/KDE/kdebase/apps/; revision=1102749

1 files changed, 105 insertions, 0 deletions

diff --git a/src/panels/information/kmetadatamodel.h b/src/panels/information/kmetadatamodel.h
new file mode 100644
index 000000000..4b12563d3
--- /dev/null
+++ b/src/panels/information/kmetadatamodel.h
@@ -0,0 +1,105 @@
+/*****************************************************************************
+ * Copyright (C) 2010 by Peter Penz <[email protected]>                      *
+ *                                                                           *
+ * This library is free software; you can redistribute it and/or             *
+ * modify it under the terms of the GNU Library General Public               *
+ * License version 2 as published by the Free Software Foundation.           *
+ *                                                                           *
+ * This library is distributed in the hope that it will be useful,           *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
+ * Library General Public License for more details.                          *
+ *                                                                           *
+ * You should have received a copy of the GNU Library General Public License *
+ * along with this library; see the file COPYING.LIB.  If not, write to      *
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,      *
+ * Boston, MA 02110-1301, USA.                                               *
+ *****************************************************************************/
+
+#ifndef KMETADATAMODEL_H
+#define KMETADATAMODEL_H
+
+#include <kurl.h>
+
+#include <QObject>
+#include <QMap>
+#include <QString>
+
+
+#include <config-nepomuk.h>
+#ifdef HAVE_NEPOMUK
+    #define DISABLE_NEPOMUK_LEGACY
+    #include <nepomuk/variant.h>
+#endif
+
+class KFileItemList;
+class KUrl;
+
+/**
+ * @brief Provides the data for the KMetaDataWidget.
+ *
+ * The default implementation provides all meta data
+ * that are available due to Strigi and Nepomuk. If custom
+ * meta data should be added, the method KMetaDataModel::loadData()
+ * must be overwritten.
+ *
+ * @see KMetaDataWidget
+ */
+class KMetaDataModel : public QObject
+{
+    Q_OBJECT
+
+public:
+    explicit KMetaDataModel(QObject* parent = 0);
+    virtual ~KMetaDataModel();
+
+    /**
+     * Sets the items, where the meta data should be
+     * requested. The loading of the meta data is done
+     * asynchronously. The signal loadingFinished() is
+     * emitted, as soon as the loading has been finished.
+     * The meta data can be retrieved by
+     * KMetaDataModel::data() afterwards.
+     */
+    void setItems(const KFileItemList& items);
+    KFileItemList items() const;
+
+#ifdef HAVE_NEPOMUK
+    /**
+     * @return Meta data for the items that have been set by
+     *         KMetaDataModel::setItems(). The method should
+     *         be invoked after the signal loadingFinished() has
+     *         been received (otherwise no data will be returned).
+     */
+    QMap<KUrl, Nepomuk::Variant> data() const;
+
+protected:
+    /**
+     * Implement this method if custom meta data should be retrieved
+     * and added to the list returned by KMetaDataModel::data().
+     * Use KMetaDataModel::items() to get the list of items, where
+     * the meta data should be requested. The method is invoked in
+     * a custom thread context, so that the user interface won't get
+     * blocked if the operation takes longer. The default implementation
+     * returns an empty list.
+     */
+    virtual QMap<KUrl, Nepomuk::Variant> loadData() const;
+#endif
+
+signals:
+    /**
+     * Is emitted after the loading triggered by KMetaDataModel::setItems()
+     * has been finished.
+     */
+    void loadingFinished();
+
+private:
+    class Private;
+    Private* d;
+
+    Q_PRIVATE_SLOT(d, void slotLoadingFinished())
+
+    friend class KLoadMetaDataThread; // invokes KMetaDataObject::loadData()
+};
+
+#endif