1 /*  This file is part of the KDE project.

     2 

     3 Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 

     5 This library is free software: you can redistribute it and/or modify

     6 it under the terms of the GNU Lesser General Public License as published by

     7 the Free Software Foundation, either version 2.1 or 3 of the License.

     8 

     9 This library 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 Lesser General Public License for more details.

    13 

    14 You should have received a copy of the GNU Lesser General Public License

    15 along with this library.  If not, see <http://www.gnu.org/licenses/>.

    16 

    17 */

    18 

    19 #ifndef PHONON_MMF_ANCESTORMOVEMONITOR_H

    20 #define PHONON_MMF_ANCESTORMOVEMONITOR_H

    21 

    22 #include <QObject>

    23 #include <QHash>

    24 #include <QList>

    25 

    26 QT_BEGIN_NAMESPACE

    27 

    28 namespace Phonon

    29 {

    30 namespace MMF

    31 {

    32 class VideoOutput;

    33 

    34 class AncestorMoveMonitor : public QObject

    35 {

    36     Q_OBJECT

    37 

    38 public:

    39     explicit AncestorMoveMonitor(QObject *parent);

    40     ~AncestorMoveMonitor();

    41 

    42     /**

    43      * Register target widget for notification.

    44      *

    45      * The widget receives an ancestorMoveEvent callback when a move event

    46      * is delivered to any of its ancestors:

    47      *

    48      * If the target is already registered, this function causes its

    49      * ancestor list to be updated - therefore it should be called when

    50      * the target receives a ParentChange event.

    51      */

    52     void registerTarget(VideoOutput *target);

    53 

    54     /**

    55      * Remove target from the monitor.

    56      *

    57      * The target will no longer receive notification when move events are

    58      * delivered to its ancestors.

    59      */

    60     void unRegisterTarget(VideoOutput *target);

    61 

    62 protected:

    63     /**

    64      * Function which receives events from the global event filter.

    65      */

    66     bool eventFilter(QObject *watched, QEvent *event);

    67 

    68     void dump();

    69 

    70 private:

    71     /**

    72      * List of registered target widgets which descend from a given

    73      * ancestor.

    74      *

    75      * Note that the members of the list should be non-redundant; this

    76      * invariant is checked in debug builds.  Semantically, the value is

    77      * therefore a set, however we use QList rather than QSet for

    78      * efficiency of iteration.

    79      */

    80     typedef QList<VideoOutput *> TargetList;

    81 

    82     /**

    83      * Map from widget on which the move event occurs, to widgets which

    84      * descend from it and therefore need to be notified.

    85      */

    86     typedef QHash<QObject *, TargetList> Hash;

    87     Hash m_hash;

    88 

    89 };

    90 }

    91 }

    92 

    93 QT_END_NAMESPACE

    94 

    95 #endif