Question

I have a few game sounds, such as four different beep tones, and each one is played depending on the action the user performs. Do I need to instantiate four different AVAudioPlayer objects?

Or do I just need one main player? If I just need one, then how do I switch the file URL?

This is what I am doing now:

NSError *error;
soundPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:markedSound error:&error];

but it seems to take a few seconds to initialize. Is there a way to preload the files and switch between them quickly?

Answer 1

Continue creating as many instance as you have sounds.
After initialization, use the method prepareToPlay:

Prepares the audio player for playback by preloading its buffers.
Discussion Calling this method preloads buffers and acquires the audio
hardware needed for playback, which minimizes the lag between calling
the play method and the start of sound output.

Calling the stop method, or allowing a sound to finish playing, undoes
this setup.

For example:

NSError *error;
soundPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:markedSound error:&error];
[soundPlayer prepareToPlay];

For the moments, you only need 4 songs, so this would be premature optimization. But if later, the number of sounds you need increase a lot, you can wrap all this in a sub-class and do lazy loading. As the documentation states, using the stop method is the equivalent of unloading your file.