ground/gcs/src/plugins/coreplugin/fileiconprovider.cpp

   1 /**
   2  ******************************************************************************
   3  *
   4  * @file       fileiconprovider.cpp
   5  * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
   6  *             Parts by Nokia Corporation (qt-info@nokia.com) Copyright (C) 2009.
   7  * @addtogroup GCSPlugins GCS Plugins
   8  * @{
   9  * @addtogroup CorePlugin Core Plugin
  10  * @{
  11  * @brief The Core GCS plugin
  12  *****************************************************************************/
  13 /*
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 3 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  21  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  22  * for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License along
  25  * with this program; if not, write to the Free Software Foundation, Inc.,
  26  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  27  */
  28
  29 #include "fileiconprovider.h"
  30 #include "mimedatabase.h"
  31
  32 #include <QtGui/QApplication>
  33 #include <QtGui/QStyle>
  34 #include <QtGui/QPainter>
  35
  36 using namespace Core;
  37
  38 /*!
  39    \class FileIconProvider
  40
  41    Provides icons based on file suffixes.
  42
  43    The class is a singleton: It's instance can be accessed via the static instance() method.
  44    Plugins can register custom icons via registerIconSuffix(), and retrieve icons via the icon()
  45    method.
  46  */
  47
  48 FileIconProvider *FileIconProvider::m_instance = 0;
  49
  50 FileIconProvider::FileIconProvider()
  51     : m_unknownFileIcon(qApp->style()->standardIcon(QStyle::SP_FileIcon))
  52 {}
  53
  54 FileIconProvider::~FileIconProvider()
  55 {
  56     m_instance = 0;
  57 }
  58
  59 /*!
  60    Returns the icon associated with the file suffix in fileInfo. If there is none,
  61    the default icon of the operating system is returned.
  62  */
  63 QIcon FileIconProvider::icon(const QFileInfo &fileInfo)
  64 {
  65     const QString suffix = fileInfo.suffix();
  66     QIcon icon = iconForSuffix(suffix);
  67
  68     if (icon.isNull()) {
  69         // Get icon from OS and store it in the cache
  70
  71         // Disabled since for now we'll make sure that all icons fit with our
  72         // own custom icons by returning an empty one if we don't know it.
  73 #if defined(Q_WS_WIN) || defined(Q_WS_MAC)
  74         // This is incorrect if the OS does not always return the same icon for the
  75         // same suffix (Mac OS X), but should speed up the retrieval a lot ...
  76         icon = m_systemIconProvider.icon(fileInfo);
  77         if (!suffix.isEmpty()) {
  78             registerIconOverlayForSuffix(icon, suffix);
  79         }
  80 #else
  81         if (fileInfo.isDir()) {
  82             icon = m_systemIconProvider.icon(fileInfo);
  83         } else {
  84             icon = m_unknownFileIcon;
  85         }
  86 #endif
  87     }
  88
  89     return icon;
  90 }
  91
  92 /*!
  93    Creates a pixmap with baseicon at size and overlays overlayIcon over it.
  94  */
  95 QPixmap FileIconProvider::overlayIcon(QStyle::StandardPixmap baseIcon, const QIcon &overlayIcon, const QSize &size) const
  96 {
  97     QPixmap iconPixmap = qApp->style()->standardIcon(baseIcon).pixmap(size);
  98     QPainter painter(&iconPixmap);
  99
 100     painter.drawPixmap(0, 0, overlayIcon.pixmap(size));
 101     painter.end();
 102     return iconPixmap;
 103 }
 104
 105 /*!
 106    Registers an icon for a given suffix, overlaying the system file icon.
 107  */
 108 void FileIconProvider::registerIconOverlayForSuffix(const QIcon &icon, const QString &suffix)
 109 {
 110     QPixmap fileIconPixmap = overlayIcon(QStyle::SP_FileIcon, icon, QSize(16, 16));
 111
 112     // delete old icon, if it exists
 113     QList<QPair<QString, QIcon> >::iterator iter = m_cache.begin();
 114     for (; iter != m_cache.end(); ++iter) {
 115         if ((*iter).first == suffix) {
 116             iter = m_cache.erase(iter);
 117             break;
 118         }
 119     }
 120
 121     QPair<QString, QIcon> newEntry(suffix, fileIconPixmap);
 122     m_cache.append(newEntry);
 123 }
 124
 125 /*!
 126    Registers an icon for all the suffixes of a given mime type, overlaying the system file icon.
 127  */
 128 void FileIconProvider::registerIconOverlayForMimeType(const QIcon &icon, const MimeType &mimeType)
 129 {
 130     foreach(const QString &suffix, mimeType.suffixes())
 131     registerIconOverlayForSuffix(icon, suffix);
 132 }
 133
 134 /*!
 135    Returns an icon for the given suffix, or an empty one if none registered.
 136  */
 137 QIcon FileIconProvider::iconForSuffix(const QString &suffix) const
 138 {
 139     QIcon icon;
 140
 141 #if defined(Q_WS_WIN) || defined(Q_WS_MAC) // On Windows and Mac we use the file system icons
 142     Q_UNUSED(suffix)
 143 #else
 144     if (suffix.isEmpty()) {
 145         return icon;
 146     }
 147
 148     QList<QPair<QString, QIcon> >::const_iterator iter = m_cache.constBegin();
 149     for (; iter != m_cache.constEnd(); ++iter) {
 150         if ((*iter).first == suffix) {
 151             icon = (*iter).second;
 152             break;
 153         }
 154     }
 155 #endif
 156     return icon;
 157 }
 158
 159 /*!
 160    Returns the sole instance of FileIconProvider.
 161  */
 162 FileIconProvider *FileIconProvider::instance()
 163 {
 164     if (!m_instance) {
 165         m_instance = new FileIconProvider;
 166     }
 167     return m_instance;
 168 }