iPhone UIActivityIndicatorView not starting or stopping

Question

When I call startAnimating on a UIActivityIndicatorView, it doesn\'t start. Why is this?

[This is a blog-style self-answered question. The solution below works for

Answer 1

This question is quite useful. But one thing that is missing in the answer post is , every thing that takes long time need to be perform in separate thread not the UIActivityIndicatorView. This way it won't stop responding to UI interface.

    - (void) doLotsOFWork:(id)data {
    //  do the work here.
}

    -(void)doStuff{
    [activityIndicator startAnimating]; 
    [NSThread detachNewThreadSelector:@selector(doLotsOFWork:) toTarget:self withObject:nil]; 
    [activityIndicator stopAnimating];
}