renderer.hpp Example File

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    #ifndef RENDERER_HPP
    #define RENDERER_HPP

    #include "renderthread.hpp"

    #include <bb/cascades/Container>

    /**
     * The Renderer class encapsulates business logic of this application.
     * It transforms an image by spawning off worker threads (RenderThread), retrieves
     * the result via a signal/slot connection and then 'paints' the result in
     * the UI by generating a couple of colored Containers inside a canvas Container.
     */
    class Renderer : public QObject
    {
        Q_OBJECT

        // A property that reports whether a worker thread is currently running.
        Q_PROPERTY(bool active READ active NOTIFY activeChanged)

    public:
        Renderer(QObject *parent = 0);

        /**
         * This method is called to tell the Renderer on which Container the colored
         * blocks should be positioned.
         */
        void setCanvas(bb::cascades::Container *container);

        // This method is called whenever the user selects an image in the UI.
        Q_INVOKABLE void loadImage(const QString &name);

    public Q_SLOTS:
        // This method is called whenever the user wants to abort the current transformation of an image
        void stop();

    Q_SIGNALS:
        // The change notification signal for the active property
        void activeChanged();

    private Q_SLOTS:
        // This method is called whenever the RenderThread has finished the calculation of one block.
        void addBlock(const Block &block);

        // This method is called whenever the RenderThread has finished the complete transformation of an image
        void threadFinished();

    private:
        // The accessor method for the active property
        bool active() const;

        // The canvas container object
        bb::cascades::Container *m_container;

        // The render thread
        RenderThread *m_thread;

        // The active property
        bool m_active;
    };

    #endif