Qt with Cascades UI Examples Documentation

app.cpp Example File

streambookmarks/src/app.cpp
    /****************************************************************************
     **
     ** Portions Copyright (C) 2012 Research In Motion Limited.
     ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
     ** All rights reserved.
     ** Contact: Research In Motion Ltd. (http://www.rim.com/company/contact/)
     ** Contact: Nokia Corporation (qt-info@nokia.com)
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     ** 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.
     **
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     **
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     ** modification, are permitted provided that the following conditions are
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    #include <bb/cascades/Application>
    #include <bb/cascades/Control>
    #include <bb/cascades/QmlDocument>
    #include <bb/cascades/Page>

    #include "app.hpp"
    #include "xbelwriter.hpp"
    #include "xbelreader.hpp"

    using namespace bb::cascades;

    App::App()
    {
        // Load the main QML file and make the App object available as context property
        QmlDocument *qml = QmlDocument::create("asset:///main.qml");
        if (!qml->hasErrors()) {
            qml->setContextProperty("_app", this);
            Page *appPage = qml->createRootObject<Page>();
            if (appPage) {
                Application::instance()->setScene(appPage);

                // Retrieve the tree container control from the QML file
                m_treeContainer = appPage->findChild<Container*>("treeContainer");
            }
        }
    }

    void App::load(const QString &fileName)
    {
        // Do sanity check
        if (!m_treeContainer)
            return;

        // Update the status property
        m_status = tr("Loading...");
        emit statusChanged();

        // Clean all previous generated bookmark controls from the tree container
        m_treeContainer->removeAll();

        // Create the XBEL reader and pass the tree container it will work on
        XbelReader reader(m_treeContainer);

        // Open the XBEL file which the user has selected
        QFile file("app/native/assets/" + fileName);
        if (!file.open(QIODevice::ReadOnly))
            qWarning("unable to open file");

        // Parse XBEL file and generate the bookmark controls
        const bool ok = reader.read(&file);

        // Update the status property again
        if (ok)
            m_status = tr("Loaded successfully");
        else
            m_status = reader.errorString();

        emit statusChanged();
    }

    void App::save()
    {
        // Do sanity check
        if (!m_treeContainer)
            return;

        // Update the status property
        m_status = tr("Saving...");
        emit statusChanged();

        const QString fileName("tmp/streambookmarks.xbel");

        // Open the target file where the modified XBEL document will be written to
        QFile file(fileName);
        file.open(QIODevice::WriteOnly);

        // Create the XBEL writer on the tree container and let it generate the XBEL document from the bookmark controls
        XbelWriter writer(m_treeContainer);
        const bool ok = writer.writeFile(&file);

        // Update the status property again
        if (ok)
            m_status = tr("Saved successfully");
        else
            m_status = tr("Error while saving");

        emit statusChanged();
    }

    QString App::status() const
    {
        return m_status;
    }