app.cpp Example File

    /****************************************************************************
     **
     ** Portions Copyright (C) 2012, 2013  BlackBerry Limited.
     ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
     ** All rights reserved.
     ** Contact: BlackBerry Ltd. (http://www.blackberry.com/company/contact/)
     ** Contact: Nokia Corporation (qt-info@nokia.com)
     **
     ** This file is part of the examples of the BB10 Platform and is derived
     ** from a similar file that is part of the Qt Toolkit.
     **
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of BlackBerry, nor the name of Nokia
     **     Corporation and its Subsidiary(-ies), nor the names of its
     **     contributors may be used to endorse or promote products
     **     derived from this software without specific prior written
     **     permission.
     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
     **
     ****************************************************************************/

    #include "app.hpp"
    #include "QtObjectFormatter.hpp"

    #include <bb/data/JsonDataAccess>

    #include <bb/cascades/Application>
    #include <bb/cascades/Page>
    #include <bb/cascades/QmlDocument>

    using namespace bb::cascades;
    using namespace bb::data;

    static QString assetPath(const QString& assetName)
    {
        return QDir::currentPath() + "/app/native/assets/" + assetName;
    }

    App::App()
        : mRhsDefaultTitle(tr("Output display area"))
        , mRhsTitle(mRhsDefaultTitle)
        , mResult("results")
        , mState(Init)
    {
        // Load the UI description from main.qml
        QmlDocument *qml = QmlDocument::create("asset:///main.qml").parent(this);

        // Make the App object available to the UI as context property
        qml->setContextProperty("_app", this);

        // Create the application scene
        AbstractPane *appPage = qml->createRootObject<AbstractPane>();
        setResultAndState("  ", Init);
        Application::instance()->setScene(appPage);
    }

    QString App::jsonData() const
    {
        return mJsonData;
    }

    void App::setJsonData(const QString& data)
    {
        if (mJsonData == data)
            return;

        mJsonData = data;
        emit jsonDataChanged(data);
    }

    QString App::rhsTitle() const
    {
        return mRhsTitle;
    }

    void App::setRhsTitle(const QString& title)
    {
        if (mRhsTitle == title)
            return;

        mRhsTitle = title;
        emit rhsTitleChanged(title);
    }

    QString App::rhsText() const
    {
        return mRhsText;
    }

    void App::setRhsText(const QString& text)
    {
        if (mRhsText == text)
            return;

        mRhsText = text;
        emit rhsTextChanged(text);
    }

    QString App::result() const
    {
        return mResult;
    }

    void App::setResult(const QString& result)
    {
        if (mResult == result)
            return;

        mResult = result;
        emit resultChanged(result);
    }

    App::State App::state() const
    {
        return mState;
    }

    void App::setState(const State state)
    {
        if (mState == state)
            return;

        mState = state;
        emit stateChanged(state);
    }

    void App::loadOriginalJson()
    {
        const QString result = tr("Loading ... ");
        setResult(result);
        setRhsTitleAndText(mRhsDefaultTitle, "");
        setQtData(QVariant());

        QFile jsonFile(assetPath("snippet.json"));
        loadJsonFileRaw(result, jsonFile);
    }

    void App::convertJsonToQt()
    {
        const QString result = tr("Converting ... ");
        setResult(result);
        setRhsTitleAndText(mRhsDefaultTitle, "");
        setQtData (QVariant());

        JsonDataAccess jda;
        QVariant qtData = jda.loadFromBuffer(mJsonData);
        if (jda.hasError()) {
            const DataAccessError err = jda.error();
            const QString errorMsg = tr("Error converting JSON data: %1").arg(err.errorMessage());
            setResultAndState(errorMsg, JsonLoaded);
        } else {
            setQtData(qtData);
            const QtObjectFormatter fmt;
            setRhsTitleAndText(tr("Qt Data from JSON"), fmt.asString(qtData));
            setResultAndState(result + tr("Success"), QtDisplayed);
        }
    }

    void App::convertQtToJson()
    {
        const QString result = tr("Converting ... ");
        setResult(result);
        setRhsTitleAndText(mRhsDefaultTitle, "");

        QString jsonBuffer;
        JsonDataAccess jda;
        jda.saveToBuffer(mQtData, &jsonBuffer);
        if (jda.hasError()) {
            const DataAccessError err = jda.error();
            const QString errorMsg = tr("Error converting Qt data to JSON: %1").arg(err.errorMessage());
            setResultAndState(errorMsg, QtDisplayed);
        } else {
            setRhsTitleAndText(tr("JSON Data from Qt"), jsonBuffer);
            setResultAndState(result + tr("Success"), ReadyToWrite);
        }
    }

    void App::updateJsonDataFromQml(const QString &data)
    {
        mJsonData = data;
    }

    void App::writeToJsonFileAndReload()
    {
        const QString result = tr("Writing file ... ");
        setResult(result);

        const QDir home = QDir::home();
        QTemporaryFile file(home.absoluteFilePath("XXXXXX.json"));
        if (file.open()) {
            JsonDataAccess jda(&file);
            jda.save(mQtData, &file);
            if (jda.hasError()) {
                const DataAccessError err = jda.error();
                const QString errorMsg = tr("Error writing data to JSON file: %1").arg(err.errorMessage());
                setResultAndState(errorMsg, ReadyToWrite);
            } else {
                file.close();
                loadJsonFileRaw(tr("Reloading new JSON file ... "), file);
            }
        }
    }

    void App::loadJsonFileRaw(const QString& resultMsg, QFile& jsonFile)
    {
        if (!jsonFile.open(QFile::ReadOnly)) {
            const QString msg = tr("Failed to open JSON file: %1").arg(jsonFile.fileName());
            setJsonData (QString());
            setResultAndState(msg, Init);
            return;
        }

        const QString doc = QString::fromUtf8(jsonFile.readAll());
        setJsonData(doc);
        setResultAndState(resultMsg + tr("Success"), JsonLoaded);
    }

    void App::setQtData(const QVariant& data)
    {
        mQtData = data;
    }

    void App::setResultAndState(const QString& result, State newState)
    {
        setResult(result);
        setState(newState);
    }

    void App::setRhsTitleAndText(const QString& title, const QString& text)
    {
        setRhsTitle(title);
        setRhsText(text);
    }