[NSThread detachNewThreadSelector:@selector(loadActivityIndicator) toTarget:self withObject:loader];
puzzle_think_tank *objThinkTank = [[puzzle_think_tank alloc] initWithNibName:@"puzzle_think_tank" bundle:nil];

[self.navigationController pushViewController:objThinkTank animated:NO];
[viewActivity removeFromSuperview];
[loader stopAnimating];

- (void)loadActivityIndicator{

    NSAutoreleasePool *autoreleasepool = [[NSAutoreleasePool alloc] init];

    viewActivity = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 500, 480)];

    viewActivity.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"transparent-loader.png"]];

    viewActivity.backgroundColor = [UIColor clearColor];

    loader = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(130, 180, 50, 50)];

    [loader setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleWhiteLarge];

    loader.backgroundColor = [UIColor clearColor];

    [loader startAnimating];

    loader.hidden = NO;

    [viewActivity addSubview:loader];

    [self.view addSubview:viewActivity];

    [loader release];

    [autoreleasepool release];
}

[self.navigationController popViewControllerAnimated:NO];