Overview:
Key presses of media keys cannot be detected in the same way as other key events. Media keys, such as Play/Pause, Stop, Volume Up/Down, Rewind, and Forward keys, featured on some S60 3rd Edition devices do not generate normal key events that could be handled within the application framework, e.g. in HandleKeyEventL() or OfferKeyEventL().
Solution:
Events from media keys can be handled with the Remote Control API.
Below is a code snippet that demonstrates this. The classes used are:
CRemConInterfaceSelector
CRemConCoreApiTarget
MRemConCoreApiTargetObserver
Remote Control API requires ReadUserData capability.
//------------------------------------------------------------------------------
#include <remconcoreapitargetobserver.h> // link against RemConCoreApi.lib
#include <remconcoreapitarget.h> // and
#include <remconinterfaceselector.h> // RemConInterfaceBase.lib
class CMediaKeysTestUi : public CAknAppUi, public MRemConCoreApiTargetObserver
{
...
// From MRemConCoreApiTargetObserver
void MrccatoCommand(TRemConCoreApiOperationId aOperationId,
TRemConCoreApiButtonAction aButtonAct);
// following functions from MRemConCoreApiTargetObserver are not needed
// in this case -> use empty implementations for these:
// MrccatoPlay
// MrccatoTuneFunction
// MrccatoSelectDiskFunction
// MrccatoSelectAvInputFunction
// MrccatoSelectAudioInputFunction
private:
CRemConInterfaceSelector* iInterfaceSelector;
CRemConCoreApiTarget* iCoreTarget;
};
void CMediaKeysTestUi::ConstructL()
{
...
iInterfaceSelector = CRemConInterfaceSelector::NewL();
iCoreTarget = CRemConCoreApiTarget::NewL(*iInterfaceSelector, *this);
iInterfaceSelector->OpenTargetL();
}
// ----------------------------------------------------------------------------
// MrccatoCommand()
// Receives events (press/click/release) from the following buttons:
// 'Play/Pause', 'Volume Up', 'Volume Down', 'Stop', 'Rewind', 'Forward'
// ----------------------------------------------------------------------------
void CMediaKeysTestUi::MrccatoCommand(TRemConCoreApiOperationId aOperationId,
TRemConCoreApiButtonAction aButtonAct)
{
TRequestStatus status;
switch( aOperationId )
{
case ERemConCoreApiPausePlayFunction:
{
switch (aButtonAct)
{
case ERemConCoreApiButtonPress:
// Play/Pause button pressed
break;
case ERemConCoreApiButtonRelease:
// Play/Pause button released
break;
case ERemConCoreApiButtonClick:
// Play/Pause button clicked
break;
default:
// Play/Pause unknown action
break;
}
//Send the response back to Remcon server
iCoreTarget->PausePlayFunctionResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiStop:
{
switch (aButtonAct)
{
// see above (case ERemConCoreApiPausePlayFunction)
// for possible actions
}
iCoreTarget->StopResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiRewind:
{
switch (aButtonAct)
{
// see above for possible actions
}
iCoreTarget->RewindResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiForward:
{
switch (aButtonAct)
{
// see above for possible actions
}
iCoreTarget->ForwardResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiVolumeUp:
{
switch (aButtonAct)
{
// see above for possible actions
}
iCoreTarget->VolumeUpResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiVolumeDown:
{
switch (aButtonAct)
{
// see above for possible actions
}
iCoreTarget->VolumeDownResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiFastForward:
{
switch (aButtonAct)
{
// see above for possible actions
}
iCoreTarget->FastForwardResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
case ERemConCoreApiBackward:
{
switch (aButtonAct)
{
// see above for possible actions
}
iCoreTarget->BackwardResponse(status, KErrNone);
User::WaitForRequest(status);
break;
}
default:
break;
}
}
//------------------------------------------------------------------------------
Note that when pressed and held, media keys do not automatically repeat the commands. If repeat functionality is required, it has to be implemented with (CPeriodic) timers.