Provide functionality for auto-expanding folders (the whole patch has been provided by Simon St James). The setting is currently not offered in the GUI, as some minor remaining issues must be fixed.

CCMAIL: [email protected]

svn path=/trunk/KDE/kdebase/apps/; revision=845975

1 files changed, 102 insertions, 0 deletions

diff --git a/src/folderexpander.h b/src/folderexpander.h
new file mode 100644
index 000000000..136b6b152
--- /dev/null
+++ b/src/folderexpander.h
@@ -0,0 +1,102 @@
+/***************************************************************************
+ *   Copyright (C) 2008 by Simon St James <[email protected]>  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 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 General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
+ ***************************************************************************/
+
+#ifndef FOLDEREXPANDER_H
+#define FOLDEREXPANDER_H
+
+// Needs to be exported as treesidebarpage uses it.
+#include "libdolphin_export.h"
+
+#include <QObject>
+#include <QPoint>
+
+class QAbstractItemView;
+class QTreeView;
+class QTimer;
+class QSortFilterProxyModel;
+class QModelIndex;
+class KDirModel;
+
+/* Grants "auto expand"/ "spring-loaded folders" to 
+   the provided view.  Qt has its own auto-expand 
+   mechanism, but this works only for QTreeView and
+   does not play well with our auto-scrolling in
+   the Folders pane.  Auto-expansion is enabled by default.
+
+   If the provided view is a QTreeView, the expanded state
+   is automatically toggled on hover.  Otherwise, the enterDir()
+   signal is emitted, and the caller needs to ensure that
+   the requested directory is entered.
+
+   The FolderExpander becomes a child of the provided view */
+
+/**
+ * Grants auto expanding functionality to the provided item view.
+ * Qt has its own auto expand mechanism, but this works only
+ * for QTreeView. Auto expanding of folders is turned on
+ * per default.
+ *
+ * If the provided view is an instance of the class QTreeView, the
+ * expanded of the directory is automatically done on hover. Otherwise
+ * the enterDir() signal is emitted and the caller needs to ensure that
+ * the requested directory is entered.
+ *
+ * The FolderExpander becomes a child of the provided view.
+ */
+class LIBDOLPHINPRIVATE_EXPORT FolderExpander : public QObject
+{
+    Q_OBJECT
+    
+public:
+    FolderExpander(QAbstractItemView* view, QSortFilterProxyModel* proxyModel);
+    virtual ~FolderExpander();
+  
+    void setEnabled(bool enabled);
+    bool enabled() const;
+  
+signals:
+    /**
+     * Is emitted if the directory \a dirModelIndex should be entered. The
+     * signal is not emitted when a QTreeView is used, as the entering of
+     * the directory is already provided by expanding the tree node.
+     */
+    void enterDir(const QModelIndex& dirModelIndex);
+    
+private slots:
+    void viewScrolled();
+    void autoExpandTimeout();
+
+private: 
+    bool m_enabled;
+    
+    QAbstractItemView* m_view;
+    QSortFilterProxyModel* m_proxyModel;
+
+    QTimer* m_autoExpandTriggerTimer;
+    QPoint m_autoExpandPos;
+
+    static const int AUTO_EXPAND_DELAY = 700;
+
+    /**
+     * Watchs the drag/move events for the view to decide
+     * whether auto expanding of a folder should be triggered.
+     */
+    bool eventFilter(QObject* watched, QEvent* event);
+};
+#endif