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# qdeclarativefolderlistmodel.cpp Example File

src/imports/folderlistmodel/qdeclarativefolderlistmodel.cpp

     /****************************************************************************
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     #include "qdeclarativefolderlistmodel.h"
     #include <QDirModel>
     #include <QDebug>
     #include <qdeclarativecontext.h>

     #ifndef QT_NO_DIRMODEL

     class QDeclarativeFolderListModelPrivate
     {
     public:
         QDeclarativeFolderListModelPrivate()
             : sortField(QDeclarativeFolderListModel::Name), sortReversed(false), count(0) {
             nameFilters << QLatin1String("*");
         }

         void updateSorting() {
             QDir::SortFlags flags = 0;
             switch(sortField) {
             case QDeclarativeFolderListModel::Unsorted:
                 flags |= QDir::Unsorted;
                 break;
             case QDeclarativeFolderListModel::Name:
                 flags |= QDir::Name;
                 break;
             case QDeclarativeFolderListModel::Time:
                 flags |= QDir::Time;
                 break;
             case QDeclarativeFolderListModel::Size:
                 flags |= QDir::Size;
                 break;
             case QDeclarativeFolderListModel::Type:
                 flags |= QDir::Type;
                 break;
             }

             if (sortReversed)
                 flags |= QDir::Reversed;

             model.setSorting(flags);
         }

         QDirModel model;
         QUrl folder;
         QStringList nameFilters;
         QModelIndex folderIndex;
         QDeclarativeFolderListModel::SortField sortField;
         bool sortReversed;
         int count;
     };

     /*!
         \qmlclass FolderListModel QDeclarativeFolderListModel
         \ingroup qml-working-with-data
         \brief The FolderListModel provides a model of the contents of a file system folder.

         FolderListModel provides access to information about the contents of a folder
         in the local file system, exposing a list of files to views and other data components.

         \note This type is made available by importing the \c Qt.labs.folderlistmodel module.
         \e{Elements in the Qt.labs module are not guaranteed to remain compatible
         in future versions.}

         \bold{import Qt.labs.folderlistmodel 1.0}

         The \l folder property specifies the folder to access. Information about the
         files and directories in the folder is supplied via the model's interface.
         Components access names and paths via the following roles:

         \list
         \o fileName
         \o filePath
         \endlist

         Additionally a file entry can be differentiated from a folder entry via the
         isFolder() method.

         \section1 Filtering

         Various properties can be set to filter the number of files and directories
         exposed by the model.

         The \l nameFilters property can be set to contain a list of wildcard filters
         that are applied to names of files and directories, causing only those that
         match the filters to be exposed.

         Directories can be included or excluded using the \l showDirs property, and
         navigation directories can also be excluded by setting the \l showDotAndDotDot
         property to false.

         It is sometimes useful to limit the files and directories exposed to those
         that the user can access. The \l showOnlyReadable property can be set to
         enable this feature.

         \section1 Example Usage

         The following example shows a FolderListModel being used to provide a list
         of QML files in a \l ListView:

         \snippet doc/src/snippets/declarative/folderlistmodel.qml 0

         \section1 Path Separators

         Qt uses "/" as a universal directory separator in the same way that "/" is
         used as a path separator in URLs. If you always use "/" as a directory
         separator, Qt will translate your paths to conform to the underlying
         operating system.

         \sa {QML Data Models}
     */

     QDeclarativeFolderListModel::QDeclarativeFolderListModel(QObject *parent)
         : QAbstractListModel(parent)
     {
         QHash<int, QByteArray> roles;
         roles[FileNameRole] = "fileName";
         roles[FilePathRole] = "filePath";
         setRoleNames(roles);

         d = new QDeclarativeFolderListModelPrivate;
         d->model.setFilter(QDir::AllDirs | QDir::Files | QDir::Drives | QDir::NoDotAndDotDot);
         connect(&d->model, SIGNAL(rowsInserted(const QModelIndex&,int,int))
                 , this, SLOT(inserted(const QModelIndex&,int,int)));
         connect(&d->model, SIGNAL(rowsRemoved(const QModelIndex&,int,int))
                 , this, SLOT(removed(const QModelIndex&,int,int)));
         connect(&d->model, SIGNAL(dataChanged(const QModelIndex&,const QModelIndex&))
                 , this, SLOT(handleDataChanged(const QModelIndex&,const QModelIndex&)));
         connect(&d->model, SIGNAL(modelReset()), this, SLOT(refresh()));
         connect(&d->model, SIGNAL(layoutChanged()), this, SLOT(refresh()));
     }

     QDeclarativeFolderListModel::~QDeclarativeFolderListModel()
     {
         delete d;
     }

     QVariant QDeclarativeFolderListModel::data(const QModelIndex &index, int role) const
     {
         QVariant rv;
         QModelIndex modelIndex = d->model.index(index.row(), 0, d->folderIndex);
         if (modelIndex.isValid()) {
             if (role == FileNameRole)
                 rv = d->model.data(modelIndex, QDirModel::FileNameRole).toString();
             else if (role == FilePathRole)
                 rv = QUrl::fromLocalFile(d->model.data(modelIndex, QDirModel::FilePathRole).toString());
         }
         return rv;
     }

     /*!
         \qmlproperty int FolderListModel::count

         Returns the number of items in the current folder that match the
         filter criteria.
     */
     int QDeclarativeFolderListModel::rowCount(const QModelIndex &parent) const
     {
         Q_UNUSED(parent);
         return d->count;
     }

     /*!
         \qmlproperty string FolderListModel::folder

         The \a folder property holds a URL for the folder that the model is
         currently providing.

         The value is a URL expressed as a string, and must be a \c file: or \c qrc:
         URL, or a relative URL.

         By default, the value is an invalid URL.
     */
     QUrl QDeclarativeFolderListModel::folder() const
     {
         return d->folder;
     }

     void QDeclarativeFolderListModel::setFolder(const QUrl &folder)
     {
         if (folder == d->folder)
             return;
         QModelIndex index = d->model.index(folder.toLocalFile());
         if ((index.isValid() && d->model.isDir(index)) || folder.toLocalFile().isEmpty()) {

             d->folder = folder;
             QMetaObject::invokeMethod(this, "refresh", Qt::QueuedConnection);
             emit folderChanged();
         }
     }

     /*!
         \qmlproperty url FolderListModel::parentFolder

         Returns the URL of the parent of of the current \l folder.
     */
     QUrl QDeclarativeFolderListModel::parentFolder() const
     {
         QString localFile = d->folder.toLocalFile();
         if (!localFile.isEmpty()) {
             QDir dir(localFile);
     #if defined(Q_OS_SYMBIAN) || defined(Q_OS_WIN)
             if (dir.isRoot())
                 dir.setPath("");
             else
     #endif
                 dir.cdUp();
             localFile = dir.path();
         } else {
             int pos = d->folder.path().lastIndexOf(QLatin1Char('/'));
             if (pos == -1)
                 return QUrl();
             localFile = d->folder.path().left(pos);
         }
         return QUrl::fromLocalFile(localFile);
     }

     /*!
         \qmlproperty list<string> FolderListModel::nameFilters

         The \a nameFilters property contains a list of file name filters.
         The filters may include the ? and * wildcards.

         The example below filters on PNG and JPEG files:

         \qml
         FolderListModel {
             nameFilters: [ "*.png", "*.jpg" ]
         }
         \endqml

         \note Directories are not excluded by filters.
     */
     QStringList QDeclarativeFolderListModel::nameFilters() const
     {
         return d->nameFilters;
     }

     void QDeclarativeFolderListModel::setNameFilters(const QStringList &filters)
     {
         d->nameFilters = filters;
         d->model.setNameFilters(d->nameFilters);
     }

     void QDeclarativeFolderListModel::classBegin()
     {
     }

     void QDeclarativeFolderListModel::componentComplete()
     {
         if (!d->folder.isValid() || d->folder.toLocalFile().isEmpty() || !QDir().exists(d->folder.toLocalFile()))
             setFolder(QUrl(QLatin1String("file://")+QDir::currentPath()));

         if (!d->folderIndex.isValid())
             QMetaObject::invokeMethod(this, "refresh", Qt::QueuedConnection);
     }

     /*!
         \qmlproperty enumeration FolderListModel::sortField

         The \a sortField property contains field to use for sorting.  sortField
         may be one of:
         \list
         \o Unsorted - no sorting is applied.  The order is system default.
         \o Name - sort by filename
         \o Time - sort by time modified
         \o Size - sort by file size
         \o Type - sort by file type (extension)
         \endlist

         \sa sortReversed
     */
     QDeclarativeFolderListModel::SortField QDeclarativeFolderListModel::sortField() const
     {
         return d->sortField;
     }

     void QDeclarativeFolderListModel::setSortField(SortField field)
     {
         if (field != d->sortField) {
             d->sortField = field;
             d->updateSorting();
         }
     }

     /*!
         \qmlproperty bool FolderListModel::sortReversed

         If set to true, reverses the sort order.  The default is false.

         \sa sortField
     */
     bool QDeclarativeFolderListModel::sortReversed() const
     {
         return d->sortReversed;
     }

     void QDeclarativeFolderListModel::setSortReversed(bool rev)
     {
         if (rev != d->sortReversed) {
             d->sortReversed = rev;
             d->updateSorting();
         }
     }

     /*!
         \qmlmethod bool FolderListModel::isFolder(int index)

         Returns true if the entry \a index is a folder; otherwise
         returns false.
     */
     bool QDeclarativeFolderListModel::isFolder(int index) const
     {
         if (index != -1) {
             QModelIndex idx = d->model.index(index, 0, d->folderIndex);
             if (idx.isValid())
                 return d->model.isDir(idx);
         }
         return false;
     }

     void QDeclarativeFolderListModel::refresh()
     {
         d->folderIndex = QModelIndex();
         if (d->count) {
             emit beginRemoveRows(QModelIndex(), 0, d->count-1);
             d->count = 0;
             emit endRemoveRows();
         }
         d->folderIndex = d->model.index(d->folder.toLocalFile());
         int newcount = d->model.rowCount(d->folderIndex);
         if (newcount) {
             emit beginInsertRows(QModelIndex(), 0, newcount-1);
             d->count = newcount;
             emit endInsertRows();
         }
     }

     void QDeclarativeFolderListModel::inserted(const QModelIndex &index, int start, int end)
     {
         if (index == d->folderIndex) {
             emit beginInsertRows(QModelIndex(), start, end);
             d->count = d->model.rowCount(d->folderIndex);
             emit endInsertRows();
         }
     }

     void QDeclarativeFolderListModel::removed(const QModelIndex &index, int start, int end)
     {
         if (index == d->folderIndex) {
             emit beginRemoveRows(QModelIndex(), start, end);
             d->count = d->model.rowCount(d->folderIndex);
             emit endRemoveRows();
         }
     }

     void QDeclarativeFolderListModel::handleDataChanged(const QModelIndex &start, const QModelIndex &end)
     {
         if (start.parent() == d->folderIndex)
             emit dataChanged(index(start.row(),0), index(end.row(),0));
     }

     /*!
         \qmlproperty bool FolderListModel::showDirs

         If true, directories are included in the model; otherwise only files
         are included.

         By default, this property is true.

         Note that the nameFilters are not applied to directories.

         \sa showDotAndDotDot
     */
     bool QDeclarativeFolderListModel::showDirs() const
     {
         return d->model.filter() & QDir::AllDirs;
     }

     void  QDeclarativeFolderListModel::setShowDirs(bool on)
     {
         if (!(d->model.filter() & QDir::AllDirs) == !on)
             return;
         if (on)
             d->model.setFilter(d->model.filter() | QDir::AllDirs | QDir::Drives);
         else
             d->model.setFilter(d->model.filter() & ~(QDir::AllDirs | QDir::Drives));
     }

     /*!
         \qmlproperty bool FolderListModel::showDotAndDotDot

         If true, the "." and ".." directories are included in the model; otherwise
         they are excluded.

         By default, this property is false.

         \sa showDirs
     */
     bool QDeclarativeFolderListModel::showDotAndDotDot() const
     {
         return !(d->model.filter() & QDir::NoDotAndDotDot);
     }

     void  QDeclarativeFolderListModel::setShowDotAndDotDot(bool on)
     {
         if (!(d->model.filter() & QDir::NoDotAndDotDot) == on)
             return;
         if (on)
             d->model.setFilter(d->model.filter() & ~QDir::NoDotAndDotDot);
         else
             d->model.setFilter(d->model.filter() | QDir::NoDotAndDotDot);
     }

     /*!
         \qmlproperty bool FolderListModel::showOnlyReadable

         If true, only readable files and directories are shown; otherwise all files
         and directories are shown.

         By default, this property is false.

         \sa showDirs
     */
     bool QDeclarativeFolderListModel::showOnlyReadable() const
     {
         return d->model.filter() & QDir::Readable;
     }

     void QDeclarativeFolderListModel::setShowOnlyReadable(bool on)
     {
         if (!(d->model.filter() & QDir::Readable) == !on)
             return;
         if (on)
             d->model.setFilter(d->model.filter() | QDir::Readable);
         else
             d->model.setFilter(d->model.filter() & ~QDir::Readable);
     }

     #endif // QT_NO_DIRMODEL