How to implement activitity indicator for maps on clicking the alert view?

I am new to iphone development.I am creating a map application.I want to display the activity indicator rotating when i click ok for the alert view "Do you want to load the current location". Since this alert is given default by ipod how can i give activit开发者_如何转开发y indicator for it? Please help me out.Please guide me.Thanks.

In the delegate for your UIAlertView, the UIAlertViewDelegate, you can make a call like this to make the activity indicator start spinning:

[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible: YES];

Then when you are done loading, stop the activity indicator with the same call.