Sometimes you want to tell the user that something’s happening behind the scenes and that there’s no need to panic. While your process is happening you can display a “spinning gear” in the middle of your screen.
One way of doing this is via a UIActivityIndicatorView.
You can create them in Interface Builder, but it’s very easy to create one and show it if and when necessary. Here’s how:
- (UIActivityIndicatorView *)indicator {
if (!_indicator) {
_indicator = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
}
return _indicator;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.indicator.center = self.view.center;
[self.view addSubview:self.indicator];
}
This creates it in the centre of your UI, but it’s invisible until switched on like so:
// to start spinning [self.indicator startAnimating]; // and to stop it again [self.indicator stopAnimating];
The UIActivityIndicatorView has a property that automatically hides it when stopped, so all we have to worry about is starting and stopping it when necessary.