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Contents 1 Overview 2 Header 3 Source 4 Application 5 More information

Overview

This application uses the accelerometer simulating a real hourglass in a Nokia N95. Every time you change device's position, an observer updates the acceleration values in each axis, ranging from -360 to 360. The following code snippet shows how to detect sensors in the device.

Header

//SensorApi header
#include <rrsensorapi.h>
 
//CGravitation class inherits an interface MRRSensorDataListener
class CGravitationAppView : public CHourglass,...,MRRSensorDataListener
{
	public:
	   ...
	   //Virtual function inherits from MRRSensorDataListener
	   void  HandleDataEventL (TRRSensorInfo aSensor, TRRSensorEvent aEvent);
	   ...
 
	private:
	   //Instance of CRRSensorApi
	   CRRSensorApi* iSensorApi;

Source

void CGravitationAppView::ConstructL( const TRect& aRect )
{
   ...	
 
   //Creating an array of sensors 
   RArray< TRRSensorInfo > sensorInfoArray;
 
   //Using FindSensorsL to find all sensors in the device and
   //fill the array with the available sensors
   CRRSensorApi::FindSensorsL(sensorInfoArray);
 
   if(sensorInfoArray.Count() > 0)
   {
         //Constructs the iSensorApi with an sensor in the array
         iSensorApi = CRRSensorApi::NewL(sensorInfoArray[1]);
         iSensorApi -> AddDataListener(this);
   }
   else
      User::Leave(KErrNotSupported);
      ...
}
 
CgravitationAppView::~CGravitationAppView()
{
   ...
   //releases memory allocated 
   if(iSensorApi)
   {
      delete iSensorApi;
      iSensorApi = NULL;
   }
   
   ...
}
 
 
//HandleDataEventL's implementation, Callback that updates the acceleration
void CGravitationAppView::HandleDataEventL (TRRSensorInfo aSensor, TRRSensorEvent aEvent)
{
 
   TInt i;
 
   for(i = 0; i < iGrains.Count(); i++)
   {
      iGrains[i]->SetAcelXY(-aEvent.iSensorData2, -aEvent.iSensorData1);
   }
 
}

Application

More information

See More: http://efforts.embedded.ufcg.edu.br/symbiancpp/