Completion handler is not called on iOS7 GM

Question

I'm using AVAssetWriter, and it is perfectly working on iOS6.

The problem is, when I called finishWritingWithCompletionHandler, the completion handler is not called on iOS7 GM.

I called markAsFinished, and even endSessionAtSourceTime before I call finishWritingWithCompletionHandler.

It works fine on iOS6.

And even more, on iOS7, it works some times, and then it doesn't work again.

I don't know why, but it works if I call the method using alert view. So I tried performSelectorOnMainThread and inBackground, but it didn't help.

Any ideas?

Answer 1

Apparently you need to retain the assetWriter now.

You might try retaining with a strong property it and see if your completion handler gets called. (Be sure to nil that property in completion handler.)

Answer 2

Ray Fix, you are right. We need to retain assetWriter. The easiest way is to use it inside the finishWritingWithCompletionHandler block:

        NSError *error = nil;

        AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:path]
                                                                   fileType:AVFileType3GPP
                                                                      error:&error];
        //startWriting, session etc.  

        [videoWriter finishWritingWithCompletionHandler:^{
                NSLog(@"%@",videoWriter);
                NSLog(@"Write Ended");
            }];