main.cpp Example File

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 ** This file is part of the QtSensors module of the Qt Toolkit.
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 #include <QtCore>
 #include <qsensor.h>

 class Filter : public QSensorFilter
 {
     int lastPercent;
 public:
     Filter()
         : QSensorFilter()
         , lastPercent(0)
     {
     }

     bool filter(QSensorReading *reading)
     {
         int percent = reading->property("chanceOfBeingEaten").value<qreal>() * 100;
         if (percent == 0) {
             qDebug() << "It is light. You are safe from Grues.";
         } else if (lastPercent == 0) {
             qDebug() << "It is dark. You are likely to be eaten by a Grue.";
         }
         if (percent == 100) {
             qDebug() << "You have been eaten by a Grue!";
             QCoreApplication::instance()->quit();
         } else if (percent)
             qDebug() << "Your chance of being eaten by a Grue:" << percent << "percent.";
         lastPercent = percent;
         return false;
     }
 };

 int main(int argc, char **argv)
 {
     QCoreApplication app(argc, argv);

     QSensor sensor("GrueSensor");

     Filter filter;
     sensor.addFilter(&filter);
     sensor.start();

     if (!sensor.isActive()) {
         qWarning("The Grue sensor didn't start. You're on your own!");
         return 1;
     }

     return app.exec();
 }