messageviewer/iconnamecache.h

   1 /* Copyright 2009 Thomas McGuire <mcguire@kde.org>
   2
   3    This library is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU Library General Public License as published
   5    by the Free Software Foundation; either version 2 of the License or
   6    ( at your option ) version 3 or, at the discretion of KDE e.V.
   7    ( which shall act as a proxy as in section 14 of the GPLv3 ), any later version.
   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 GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public License
  15    along with this library; see the file COPYING.LIB.  If not, write to
  16    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17    Boston, MA 02110-1301, USA.
  18 */
  19 #ifndef ICONNAMECACHE_H
  20 #define ICONNAMECACHE_H
  21
  22 #include "messageviewer_export.h"
  23 #include <QMap>
  24 #include <QString>
  25
  26 namespace MessageViewer {
  27
  28 /**
  29  * This class is a replacement for KIconLoader::iconPath(), because the iconPath()
  30  * function can be slow for non-existing icons or icons that fall back to a generic icon.
  31  * Reason is that KIconLoader does slow system calls for finding the icons.
  32  *
  33  * The IconNameCache caches the result of iconPath() in a map and solves the slowness.
  34  */
  35 class MESSAGEVIEWER_EXPORT IconNameCache
  36 {
  37   public:
  38
  39     static IconNameCache *instance();
  40     QString iconPath( const QString &name, int size ) const;
  41
  42   private:
  43
  44     class Entry
  45     {
  46       public:
  47         QString fileName;
  48         int size;
  49
  50         bool operator < ( const Entry &other ) const;
  51     };
  52
  53     mutable QMap<Entry,QString> mCachedEntries;
  54 };
  55
  56 }
  57 #endif