How to set grey color background for UIActivityIndicator when loading on UIView in iOS

Question

I currently have a UIActivityIndicator appearing on screen for a second or two. I would like to set grey out the background as this appears on screen but I am not sure how to do this...

Here's how I have initialized the indicator so far.

- (void)viewDidLoad
{
//...

    activity = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 32.0f, 32.0f)];
    [activity setCenter:CGPointMake(160.0f, 208.0f)];
    [activity setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleGray];

    [self.tableView addSubview:activity];

    [activity startAnimating];

    [activity performSelector:@selector(stopAnimating) withObject:nil afterDelay:1.0];


}

Any help would be greatly appreciated.

Answer 1

No need for a separate view. Here's a simple mechanism:

    UIActivityIndicatorView *activity = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];

    self.activityIndicatorView = activity;
    // make the area larger
    [activity setFrame:self.view.frame;
    // set a background color
    [activity.layer setBackgroundColor:[[UIColor colorWithWhite: 0.0 alpha:0.30] CGColor]];
    CGPoint center = self.view.center;
    activity.center = center;
    [activity release];

Answer 2

You should check out the SVProgressHUD

It has options for masking the background and is dead simple to work with.

The SVProgressHUDMaskType has options to

enum {
 SVProgressHUDMaskTypeNone = 1, // allow user interactions, don't dim background UI (default)
SVProgressHUDMaskTypeClear, // disable user interactions, don't dim background UI
SVProgressHUDMaskTypeBlack, // disable user interactions, dim background UI with 50% translucent black
SVProgressHUDMaskTypeGradient // disable user interactions, dim background UI with translucent radial gradient (a-la-alertView)
};`