qtmobility/examples/sensors/small_screen_sensors/freefallform.cpp
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Mon, 03 May 2010 13:18:40 +0300
changeset 4 90517678cc4f
child 5 453da2cfceef
permissions -rw-r--r--
Revision: 201015 Kit: 201018

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#include "freefallform.h"

const int KTreshold = 2;

FreeFallForm::FreeFallForm(QWidget *parent)
    : QWidget(parent)
{
    setupUi(this);
    dropItLabel->setText("");

    m_accelerationSensor.addFilter(this);
    m_accelerationSensor.start();
    m_freeFallState = StateNotStarted;
}

void FreeFallForm::on_setupButton_clicked()
{
    setupButton->setDisabled(true);
    dropItLabel->setText("Drop it!");
    freeFallTimeLabel->setText("-");
    freeFallHeightLabel->setText("-");
    m_freeFallState = StateSetup;
}

bool FreeFallForm::filter(QAccelerometerReading *reading)
{
    switch (m_freeFallState) {
    case StateSetup:
        if (abs(reading->x()) < KTreshold && abs(reading->y()) < KTreshold && abs(reading->z()) < KTreshold) {
            m_freeFallTimer.start();
            m_freeFallState = StateFalling;
        }
        break;
    case StateFalling:
        if (abs(reading->x()) > KTreshold || abs(reading->y()) > KTreshold || abs(reading->z()) > KTreshold) {
            freeFallTimeLabel->setNum(m_freeFallTimer.elapsed());
            qreal t = (qreal(m_freeFallTimer.elapsed()) / 1000);
            freeFallHeightLabel->setNum(9.81 / 2 * t * t);
            m_freeFallState = StateNotStarted;
            setupButton->setEnabled(true);
            setupButton->setFocus();
            dropItLabel->setText("");
        }
        break;
    default:
        break;
    }

    return false;
}