Local file plays with AVAudioPlayer but not with AVPlayer?

Question

(Note: The code here is Monotouch/C#, however Objective-C Answers are welcome!)

Im using AVPlayer as my app plays iPod library files as well as local mp3/m4a files. The playback of iPod library files is fine, however I cannot seem to get the AVPlayer to play local mp3 files.

For example, this code works:

NSUrl url;
AVAudioPlayer player2;

url = NSUrl.FromFilename(Path.Combine(Constants.TrackCacheLocation , songPath));

/* The url variable has the value file://localhost/private/var/mobile/Applications/B1ED2576-4398-43F3-8573-2FA3A0342265/Documents/Cache/Remote/dcaad4ff-452e-4d91-8788-c018e6b286f2.mp3 */

player2 = AVAudioPlayer.FromUrl(url);
player2.Play();

The above works fine, note that it's using AVAudioPlayer.

This doesn't (using AVPlayer):

NSUrl url;
AVPlayer player2;

url = NSUrl.FromFilename(Path.Combine(Constants.TrackCacheLocation , songPath));

/* The url variable has the value file://localhost/private/var/mobile/Applications/B1ED2576-4398-43F3-8573-2FA3A0342265/Documents/Cache/Remote/dcaad4ff-452e-4d91-8788-c018e6b286f2.mp3 */

player2 = AVPlayer.FromUrl(url);
player2.Play();

Creating an NSUrl from a local or remote web server also works (with AVPlayer), eg: http://10.0.0.1/testing/test.mp3 delays about a second or two while loading, then starts to play fine. I have a feeling im not creating my NSUrl correctly (even though it works fine for AVAudioPlayer). Any one any have ideas what could be going wrong?

Also, if I check the CurrentItem.Status of the AVPlayer it remains Unknown, it never changes to ReadyToPlay

There is no PrepareToPlay() (from what I can see in Apple's documentation) on AVPlayer, only AVAudioPlayer. — Dermot

poupou poupou · Accepted Answer · 2012-02-29T13:34:29

Many API that uses NSUrl or NSUrlRequest parameters are async by design and will have issues (or even crash) if defined as a local variable (e.g. that will be collected when your method returns when still needed by the native code).

You code above does not supply enough information about where they are created. If you're using local variables then try to promote them as fields and ensure they will exists (e.g. don't re-assign them) until you don't need the AVPlayer anymore.

Local file plays with AVAudioPlayer but not with AVPlayer?

1 Answers