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

    });
});