How to add an Indicator to UIImagePickerController - iphone

Question

I have an image picker to pick multiple images from the photo library. The picked photos are resized and saved to file in imagePickerController:didFinishPickingMediaWithInfo:. It takes a few seconds.
Could I put an indicator on the view?
I have tried to use addSubview:indicatorView in imagePickerController:didFinishPickingMediaWithInfo: method. But indicatorView doesn't appear. It gets dismissed with the imagePickerView.

Answer 1

You should add the UIActivityIndicatorView at the top of the view hierarchy or it will get dismissed with the UIPickerViewController, unless you use a callback after the resize operation and in the callback you dismiss the UIImagePickerController.
Or you could use a progress HUD like SVProgressHUD.
Hope this helps =)
We did a little chat session and solved this way:
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
dispatch_async(dispatch_get_main_queue(), ^{
UIView *primaryImage = [[UIView alloc] initWithFrame:CGRectMake(0,0,320,460)];
primaryImage.backgroundColor = [UIColor redColor];
primaryImage.alpha =0.9;
UIView *secondaryImage = [[UIView alloc] initWithFrame:CGRectMake(0,0,70,70)];
secondaryImage.center = CGPointMake(160, 240);
secondaryImage.backgroundColor = [UIColor blackColor];
secondaryImage.alpha = 0.9;
secondaryImage.layer.cornerRadius = 12;
[primaryImage addSubview:secondaryImage];
UIActivityIndicatorView *indicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0, 0, 25, 25)];
indicator.center = CGPointMake(35, 35);
[indicator setHidesWhenStopped:NO];
[secondaryImage addSubview:indicator];
[indicator startAnimating];
[indicator release];
[secondaryImage release];
[picker.view addSubview:primaryImage];
[primaryImage release];
});
// Put here the code to resize the image
dispatch_async(dispatch_get_main_queue(), ^{
// Dismiss the picker controller
});
});