is this code using UIActivityIndicatorView flawed?

Question

Is this code using UIActivityIndicatorView flawed? It appears that I don't actually get to see the indicator/spinner at all here, so is this because the view isn't drawn until the who viewDidLoad completes?

Is the only way around this to do the viewDidLoad custom work (e.g. data updates) on a separate thread? (I was hoping in this case for an easier single-thread operation). Is there a way to force the view to refresh after the "startAnimating" line perhaps prior to the data loading commencment?

Code from UITableViewController implementation:

- (void)viewDidLoad {
    // Wait indicator - Start
    self.waitView = [[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge] autorelease];
    self.waitView.hidesWhenStopped = true;
    [self.view addSubview: self.waitView];

    // Load data into tableview
    [NSThread sleepForTimeInterval: 5.0];   // Test code to simulate

    [self.waitView stopAnimating];
}

You might want to check the size and origin of the UIActivityIndicatorView. — sosborn
what is "load data into tableview"? when is stopAnimating called? — bshirley
re - size and origin of the UIActivityIndicatorView - well initially when I had startAnimating instead of stopAnimating (which I fixed) I could see the activity indicator in the top left, so I should be able to see it. — Greg

thomas thomas · Accepted Answer · 2011-06-08T06:49:40

You should also call startAnimating. Sleeping is not a good idea. I would prefer the performSelector-methods which starts a not recurring NSTimer under the hood.

Try this:

-(void) doStuff:(id)aSender
{
    [self.waitView stopAnimating];
}
-(void)viewDidLoad
{
    ...
    [self performSelector:@selector(doStuff:) withObject:self afterDelay:5.0];
}

in addtion: also set the frame- or bounds-property of the ActivityIndicatorView somewhere like sosborn said in his comment

is this code using UIActivityIndicatorView flawed?

2 Answers