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;
};
/*!
    \qmltype FolderListModel
    \instantiates QDeclarativeFolderListModel
    \inqmlmodule QtQuick
    \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
    操作系统。
    \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.
    默认情况下,此特性为 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.
    默认情况下,此特性为 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.
    默认情况下,此特性为 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