UIAlertView starts to show, screen dims, but it doesn't pop up until it's too late!

Question

I have a button which when pressed makes calls that load information from a series of URLs (about 5 seconds loading time). Right before actually making those calls I want to add

Answer 1

If you have a bunch of operations to perform, in addition to performSelectorInBackground: like cescofry wrote, you can use NSOperation and NSOperationQueue.

Answer 2

when you try to retrieve data from the internet (I guess you are using something like [NSString stringWithContentsOfURL: ...]) the main thread is waiting for those data and for this reason the application cannot redraw the interface. You can try to use:

[mySourceData performSelectorInBackground:@selector(loadData) withObject:nil];

Be careful if you are using coredata to lock the NSManagedObjectContext before doing any operation on it and unlock it when you finish.

Answer 3

You probably don't want an UIAlertView for this anyway. Take a look at MBProgressHUD on GitHub.