UIPageControl 改变点的颜色

-(void)viewDidLoad{
    [super viewDidLoad];
    UIPageControl* pc = [[[UIPageControl alloc] initWithFrame:CGRectMake(100, 400, 120, 27)] autorelease];
    pc.numberOfPages = 3;
    pc.currentPage = 0;
    [pc addTarget:self action:@selector(pageChanged:) forControlEvents:UIControlEventValueChanged];
    [self.view addSubview:pc];
    [self pageChanged:pc];
}
-(void)pageChanged:(UIPageControl*)pc{
    NSArray *subViews = pc.subviews;
    for (int i = 0; i < [subViews count]; i++) {
        UIView* subView = [subViews objectAtIndex:i];
        if ([NSStringFromClass([subView class]) isEqualToString:NSStringFromClass([UIImageView class])]) {
            ((UIImageView*)subView).image = (pc.currentPage == i ? [UIImage imageNamed:@"RedPoint.png"] : [UIImage imageNamed:@"BluePoint.png"]);
        }
       
    }
}