rotationsensor.cpp Example File

    /*
     * Copyright (c) 2011, 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 "rotationsensor.hpp"

    #include <bb/cascades/OrientationSupport>

    #include <QDebug>

    using namespace bb::cascades;

    RotationSensor::RotationSensor(QObject *parent)
        : QObject(parent)
        , m_rotation(0)
    {
        // We'd like to lock to the initial orientation
        OrientationSupport::instance()->setSupportedDisplayOrientation(SupportedDisplayOrientation::CurrentLocked);

        // At first we have to connect to the sensor backend...
        if (!m_rotationSensor.connectToBackend()) {
            qWarning() << "Cannot connect to rotation sensor backend!";
        }

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

        // Start gathering the data
        m_rotationSensor.start();
    }

    qreal RotationSensor::rotation() const
    {
        return m_rotation;
    }

    bool RotationSensor::filter(QRotationReading *reading)
    {
        const qreal x = reading->x();
        const qreal y = reading->y();

        if (x > 0 && x < 90) {
            if (y > 0) { // top-left quadrant
                m_rotation = (x - 90);
            } else { // top-right quadrant
                m_rotation = (90 - x);
            }
        } else { // bottom-left quadrant
            if (y > 0) {
                m_rotation = (-90 + x);
            } else { // bottom right quadrant
                m_rotation = (90 - x);
            }
        }

        emit rotationChanged();

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