Namespaces
Variants
Actions
Revision as of 05:29, 7 August 2012 by hamishwillee (Talk | contribs)

How to handle multiple sounds in Java ME

Jump to: navigation, search
Article Metadata

Code Example
Tested with
Devices(s): C3-01, Asha 305, E7-00

Compatibility
Platform(s): S40, Symbian Belle
Device(s): All

Article
Created: jaakl (15 Sep 2009)
Updated: skalogir (04 Nov 2011)
Reviewed: skalogir (19 May 2011)
Last edited: hamishwillee (07 Aug 2012)

Most phones will throw an exception if you try to keep two sounds loaded at the same time, so the trick is to deallocate the previous sound before you play the next one. The code below shows a SoundManager class, which keeps track of all the sounds in your midlet in a hashtable. It also keeps track of the time that the last sound was played, because if you try to play two sounds too close to each other it will fail in most phones.

import java.io.InputStream;
import java.util.Enumeration;
import java.util.Hashtable;
import javax.microedition.media.Manager;
import javax.microedition.media.Player;
 
 
public class SoundManager
{
private static Hashtable mapSound = new Hashtable();
private static long timeLastSound = 0;
private static boolean enabled = true;
 
static public Player getPlayer(String sound)
{
Player player;
player = (Player)mapSound.get(sound);
if (player == null)
{
try
{
String fileSpec = "/";
fileSpec += sound;
InputStream is = SoundManager.class.getResourceAsStream(fileSpec);
if (fileSpec.endsWith("amr"))
player = Manager.createPlayer(is, "audio/amr");
else if (fileSpec.endsWith("mid"))
player = Manager.createPlayer(is, "audio/midi");
mapSound.put(sound, player);
}
catch (Exception ex)
{
DebugStuff.print(ex.toString());
}
}
return player;
}
 
public static void playSound(String sound)
{
if (!enabled) return;
if (Math.abs(System.currentTimeMillis() - timeLastSound) < 250)
{
DebugStuff.print("tried to play 2 sounds too soon");
return;
}
timeLastSound = System.currentTimeMillis();
Player player = getPlayer(sound);
try
{
Enumeration enumValues;
Player playerOther;
for (enumValues = mapSound.elements(); enumValues.hasMoreElements() ;)
{
playerOther = (Player)enumValues.nextElement();
if (playerOther != player && playerOther.getState() == Player.STARTED)
playerOther.deallocate();
}
if (player.getState() == Player.STARTED)
{
DebugStuff.print("sound already started");
return;
}
player.start();
}
catch (Exception e)
{
DebugStuff.print(e.toString());
}
}
 
public static void setEnabled(boolean enabled)
{
SoundManager.enabled = enabled;
}
 
}

How to call use the SoundManager:

SoundManager.playSound("sound1.amr");

(Notice I am using the amr format instead of wav. This is because amr is much smaller, has more or less the same quality and is equally well supported as the wav format.)

156 page views in the last 30 days.
Nokia Developer aims to help you create apps and publish them so you can connect with users around the world.

京ICP备05048969号  © Copyright Nokia 2013 All rights reserved