FAQ-0892 How can I easily implement beeps in my app?


FAQ-0892 How can I easily implement beeps in my app?

» Symbian OS » Developer Knowledgebase » FAQ-0892

Classification:	C++	Category:	Applications
Created:	07/09/2003	Modified:	10/16/2003
Number:	FAQ-0892
Platform:	Symbian OS v6.0, Symbian OS v6.1, Symbian OS v7.0, Symbian OS v7.0s

Question:
CEikonEnv::Beep() is deprecated. In order to play beeps you have to use CMdaAudioToneUtility
However this is a bit fiddly. Is there an easier way?

Answer:
From Symbian OS v6.1, CEikonEnv::Beep() and User::Beep() are deprecated.

CBeep, below, shows the implementation of a simple wrapper around CMdaAudioToneUtility that you can use instead.
The class allows you to create a CBeep with a duration and a frequency like this:

TTimeIntervalMicroSeconds d1(500000);
iBeep1=CBeep::NewL(440, d1);
and then produce a beep by calling
iBeep1->Play();

You can create more than one of these objects, each with a different tone & duration, and call Play() as required.

The class definition and implementation are provided below:

class CBeep : public CBase, public MMdaAudioToneObserver
{
public:
static CBeep* NewL(TInt aFrequency, TTimeIntervalMicroSeconds iDuration);
void Play();
~CBeep();
private:
void ConstructL(TInt aFrequency, TTimeIntervalMicroSeconds iDuration);
void MatoPrepareComplete(TInt aError);
void MatoPlayComplete(TInt aError);
private:
typedef enum TBeepState
{
EBeepNotPrepared,
EBeepPrepared,
EBeepPlaying
};
private: CMdaAudioToneUtility* iToneUtil;
TBeepState iState;
TInt iFrequency;
TTimeIntervalMicroSeconds iDuration;
};

CBeep::~CBeep()
{
delete iToneUtil;
}

CBeep* CBeep::NewL(TInt aFrequency, TTimeIntervalMicroSeconds aDuration)
{
CBeep* self=new (ELeave) CBeep();
CleanupStack::PushL(self);
self->ConstructL(aFrequency, aDuration);
CleanupStack::Pop();
return self;
};

void CBeep::ConstructL(TInt aFrequency, TTimeIntervalMicroSeconds aDuration)
{
iToneUtil=CMdaAudioToneUtility::NewL(*this);
iState=EBeepNotPrepared;
iFrequency=aFrequency;
iDuration=aDuration;
iToneUtil->PrepareToPlayTone(iFrequency,iDuration);
}

void CBeep::Play()
{
if (iState!=EBeepNotPrepared)
{
if (iState==EBeepPlaying)
{
iToneUtil->CancelPlay();
iState=EBeepPrepared;
}
}
iToneUtil->Play();
iState=EBeepPlaying;
}

void CBeep::MatoPrepareComplete(TInt aError)
{
if (aError==KErrNone)
iState=EBeepPrepared;
}

void CBeep::MatoPlayComplete(TInt aError)
{
iState=EBeepPrepared;
}