FeedReader: The feed can be moved with drag and drop to a folder

plugins/FeedReader/gui/FeedTreeWidget.cpp

@@ -0,0 +1,119 @@
+/*******************************************************************************
+ * plugins/FeedReader/gui/FeedTreeWidget.cpp                                   *
+ *                                                                             *
+ * Copyright (C) 2012 RetroShare Team <retroshare.project@gmail.com>           *
+ *                                                                             *
+ * This program is free software: you can redistribute it and/or modify        *
+ * it under the terms of the GNU Affero General Public License as              *
+ * published by the Free Software Foundation, either version 3 of the          *
+ * License, or (at your option) any later version.                             *
+ *                                                                             *
+ * This program 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 Affero General Public License for more details.                         *
+ *                                                                             *
+ * You should have received a copy of the GNU Affero General Public License    *
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.       *
+ *                                                                             *
+ *******************************************************************************/
+
+#include <QDropEvent>
+#include "FeedTreeWidget.h"
+
+FeedTreeWidget::FeedTreeWidget(QWidget *parent) : RSTreeWidget(parent)
+{
+	mDraggedItem = NULL;
+}
+
+void FeedTreeWidget::dragEnterEvent(QDragEnterEvent *event)
+{
+	mDraggedItem = currentItem();
+	RSTreeWidget::dragEnterEvent(event);
+}
+
+void FeedTreeWidget::dragLeaveEvent(QDragLeaveEvent *event)
+{
+	RSTreeWidget::dragLeaveEvent(event);
+	mDraggedItem = NULL;
+}
+
+bool FeedTreeWidget::canDrop(QDropEvent *event, QTreeWidgetItem **dropItem)
+{
+	if (dropItem) {
+		*dropItem = NULL;
+	}
+
+	if (!mDraggedItem) {
+		/* no drag item */
+		return false;
+	}
+
+	QModelIndex droppedIndex = indexAt(event->pos());
+	if (!droppedIndex.isValid()) {
+		/* no drop target */
+		return false;
+	}
+
+	QTreeWidgetItem *dropItemIntern = itemFromIndex(droppedIndex);
+	if (!dropItemIntern) {
+		/* no drop item */
+		return false;
+	}
+
+	if ((dropItemIntern->flags() & Qt::ItemIsDropEnabled) == 0) {
+		/* drop is disabled */
+		return false;
+	}
+
+	if (dropItemIntern == mDraggedItem->parent()) {
+		/* drag item parent */
+		return false;
+	}
+
+	if (dropItem) {
+		*dropItem = dropItemIntern;
+	}
+
+	return true;
+}
+
+void FeedTreeWidget::dragMoveEvent(QDragMoveEvent *event)
+{
+	if (!canDrop(event)) {
+		event->ignore();
+		return;
+	}
+
+	RSTreeWidget::dragMoveEvent(event);
+}
+
+void FeedTreeWidget::dropEvent(QDropEvent *event)
+{
+	QTreeWidgetItem *dropItem;
+	if (!canDrop(event, &dropItem)) {
+		event->ignore();
+		return;
+	}
+
+	if (!mDraggedItem) {
+		/* no drag item */
+		event->ignore();
+		return;
+	}
+
+	QTreeWidgetItem *draggedParent = mDraggedItem->parent();
+	if (!draggedParent) {
+		/* no drag item parent */
+		event->ignore();
+		return;
+	}
+
+	if (!dropItem) {
+		/* no drop item */
+		event->ignore();
+		return;
+	}
+
+	emit feedReparent(mDraggedItem, dropItem);
+}