src/folderexpander.h

   1 /***************************************************************************
   2  *   Copyright (C) 2008 by Simon St James <kdedevel@etotheipiplusone.com>  *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  18  ***************************************************************************/
  19
  20 #ifndef FOLDEREXPANDER_H
  21 #define FOLDEREXPANDER_H
  22
  23 // Needs to be exported as FoldersPanel uses it.
  24 #include "libdolphin_export.h"
  25
  26 #include <QObject>
  27 #include <QPoint>
  28
  29 class QAbstractItemView;
  30 class QTreeView;
  31 class QTimer;
  32 class QSortFilterProxyModel;
  33 class QModelIndex;
  34
  35 /**
  36  * Grants auto expanding functionality to the provided item view.
  37  * Qt has its own auto expand mechanism, but this works only
  38  * for QTreeView. Auto expanding of folders is turned on
  39  * per default.
  40  *
  41  * If the provided view is an instance of the class QTreeView, the
  42  * expansion of the directory is automatically done on hover. Otherwise
  43  * the enterDir() signal is emitted and the caller needs to ensure that
  44  * the requested directory is entered.
  45  *
  46  * The FolderExpander becomes a child of the provided view.
  47  */
  48 class LIBDOLPHINPRIVATE_EXPORT FolderExpander : public QObject
  49 {
  50     Q_OBJECT
  51
  52 public:
  53     FolderExpander(QAbstractItemView* view, QSortFilterProxyModel* proxyModel);
  54     virtual ~FolderExpander();
  55
  56     void setEnabled(bool enabled);
  57     bool enabled() const;
  58
  59 signals:
  60     /**
  61      * Is emitted if the directory \a dirModelIndex should be entered. The
  62      * signal is not emitted when a QTreeView is used, as the entering of
  63      * the directory is already provided by expanding the tree node.
  64      */
  65     void enterDir(const QModelIndex& dirModelIndex);
  66
  67
  68 private slots:
  69     void viewScrolled();
  70     void autoExpandTimeout();
  71
  72 private:
  73     bool m_enabled;
  74
  75     QAbstractItemView* m_view;
  76     QSortFilterProxyModel* m_proxyModel;
  77
  78     QTimer* m_autoExpandTriggerTimer;
  79     QPoint m_autoExpandPos;
  80
  81     static const int AUTO_EXPAND_DELAY = 700;
  82
  83     /**
  84      * Watchs the drag/move events for the view to decide
  85      * whether auto expanding of a folder should be triggered.
  86      */
  87     bool eventFilter(QObject* watched, QEvent* event);
  88 };
  89 #endif