Starting Audio Play

This document describes how to play audio using DevSound.

Introduction

To play audio data, you have to do the following:

Constructing and initializing

Use the CMMFDevSound::NewL() method to construct a new instance of DevSound.

After construction, use an CMMFDevSound::InitializeL() method to initialize DevSound to play audio. This method requires that you specify the DevSound observer class to handle callbacks.

Once initialization has completed, successfully or otherwise, DevSound calls the MDevSoundObserver::InitializeComplete() function.

Configuring

The following settings can be configured before or during audio play:

  • To change the volume of the audio device to a specific value, use the CMMFDevSound::SetVolume() function. The volume can be set to any value from 0 to CMMFDevSound::MaxVolume().

  • To set the speaker balance, use the CMMFDevSound::SetPlayBalanceL() function. This function has two parameters:

    • aLeftPercentage - the left speaker volume percentage.

    • aRightPercentage - the right speaker volume percentage.

  • To set the priority setting for this instance of DevSound to access the audio device, use the CMMFDevSound::SetPrioritySettings() method. Priority settings are used by the Audio Policy component to resolve multiple requests to access the audio hardware.

Procedure