Question

I would like to use two soundpools in my activity. One that I will unload and release sometimes and load it with different sounds, then I unload/release again and use it again with other sounds, and another one that will always contain the same sounds and will never be unloaded. I didnt find any words about this in the documentation, so will it cause me any kind of problem?
And if I use the constant sounds with MediaPlayer instead of SoundPool? Will it cause any memory leak or problem?

Answer 1

There will be no memory leaks or sound playback issues, if you correctly handle your SoundPool and MediaPlayer objects in terms of your Activity lifecycle (see below).

First of all, you shouldn’t make “too many” SoundPool and MediaPlayer objects. This depends on the actual state of your device, but I’m sure you’ll be OK with 2 SoundPool objects and e.g. 4 MediaPlayer objects, simultaneously.

Explanation: each SoundPool reserves one native AudioTrack, and each MediaPlayer also reserves one native AudioTrack. Therefore, with 2 SoundPool and 4 MediaPlayer objects, you will have 6 underlying AudioTrack objects in use. This is usually fine, as the system usually has many more free AudioTrack objects. (For more detailed information, see this topic.)

Regarding your concrete question: yes, it’s also OK to use a permanent SoundPool and another SoundPool which you recreate/release sometimes, as long as you take into account the following point:

• In the onPause() or onStop() event handler of your activity, you should release all SoundPool and MediaPlayer objects, because they use native resources. Then in your onResume() or onStart(), you can recreate them again. So your statement “… will never be unloaded” isn’t correct in this sense, because you need to handle the state of SoundPool and MediaPlayer objects across your Activity lifecycle.