TrackManager.cpp Example File

    /* Copyright (c) 2012, 2013  BlackBerry Limited.
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.apache.org/licenses/LICENSE-2.0
    *
    * Unless required by applicable law or agreed to in writing, software
    * distributed under the License is distributed on an "AS IS" BASIS,
    * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    * See the License for the specific language governing permissions and
    * limitations under the License.
    */

    #include "TrackManager.hpp"

    #include <QtCore/QDir>
    #include <QtCore/QDirIterator>

    using namespace bb::cascades;

    /**
     * A helper method to return the directory path where
     * all the recorded tracks are stored.
     */
    static QString trackStorageLocation()
    {
        return QString("data/tracks/");
    }

    /**
     * A helper method to initialize the directory where
     * all the recorded tracks are stored.
     */
    static void initializeTrackStorage()
    {
        QDir trackStorage(trackStorageLocation());
        if (!trackStorage.exists())
            QDir::root().mkpath(trackStorage.absolutePath());
    }

    TrackManager::TrackManager(QObject *parent)
        : QObject(parent)
        , m_model(new GroupDataModel(this))
        , m_trackCounter(0)
    {
        m_model->setGrouping(ItemGrouping::None);

        initializeTrackStorage();

        updateTrackInformation();
    }

    QUrl TrackManager::nextTrackUrl() const
    {
        // The next track will have the current track number incremented by one
        const int nextTrack = m_trackCounter + 1;

        // Return an URL in the form "app/native/tracks/track001.m4a"
        return QUrl(QString::fromLatin1("%1/track%2.m4a").arg(QDir(trackStorageLocation()).absolutePath())
                                                         .arg(nextTrack, 3, 10, QLatin1Char('0')));
    }

    void TrackManager::clearAllTracks()
    {
        // Iterate over all files in the track directory and delete them
        QDirIterator it(trackStorageLocation(), QDir::Files | QDir::NoDotAndDotDot);
        while (it.hasNext()) {
            it.next();

            QFile::remove(it.fileInfo().absoluteFilePath());
        }

        updateTrackInformation();
    }

    void TrackManager::update()
    {
        updateTrackInformation();
    }

    GroupDataModel* TrackManager::model() const
    {
        return m_model;
    }

    bool TrackManager::hasRecordedTracks() const
    {
        // If the model is empty, we have no recorded tracks
        return (m_model->childCount(QVariantList()) != 0);
    }

    void TrackManager::updateTrackInformation()
    {
        const bool oldHasRecordedTracks = hasRecordedTracks();

        // Clear the content of the tracks model
        m_model->clear();

        // Reset the internal track counter
        m_trackCounter = 0;

        // Iterate over the track storage directory and fill the model
        QDirIterator it(trackStorageLocation(), QDir::Files | QDir::NoDotAndDotDot);
        while (it.hasNext()) {
            it.next();

            QVariantMap entry;
            entry["name"] = it.fileName(); // used as title in the ListView
            entry["url"] = it.fileInfo().absoluteFilePath(); // used by the MediaPlayer

            m_model->insert(entry);

            m_trackCounter++;
        }

        // Emit change notification signal if the hasRecordedTracks property has changed
        if (oldHasRecordedTracks != hasRecordedTracks())
            emit hasRecordedTracksChanged();
    }