GrueDetector.cpp Example File

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    #include "GrueDetector.hpp"

    #include <QtCore/QDebug>
    #include <QtCore/QTimer>

    GrueDetector::GrueDetector(QObject *parent)
        : QObject(parent)
        , m_chance(0)
        , m_darkTimer(new QTimer(this))
    {
        // At first we have to connect to the sensor backend...
        if (!m_sensor.connectToBackend()) {
            qWarning() << "Cannot connect to light sensor backend!";
        }

        // ... and then add a filter that will process the reported data
        m_sensor.addFilter(this);

        // Start the gathering of data
        m_sensor.start();

        connect(m_darkTimer, SIGNAL(timeout()), this, SLOT(increaseChance()));
    }

    bool GrueDetector::filter(QLightReading *reading)
    {
        if (reading->lux() < 10) { // Dark enough for meeting a Grue
            if (!m_darkTimer->isActive())
                m_darkTimer->start(1000);
        } else { // everything is fine...
            m_darkTimer->stop();
            m_chance = 0;
            emit chanceChanged();
        }

        // Do no further processing of the sensor data
        return false;
    }

    void GrueDetector::increaseChance()
    {
        // Increase the chance put keep it at 100% max
        m_chance = qBound(0, m_chance + 10, 100);
        emit chanceChanged();
    }

    int GrueDetector::chance() const
    {
        return m_chance;
    }