Creating a Pop animation similar to the presentation of UIAlertView-open source projects facebook/pop

I would like to present a view in the same manner as that of UIAlertView – a pop/spring. Unfortunately subclassing UIAlertView is not an option for the view I need to present. I have written some code, but I can’t seem to get it as realistic as I would like. I would appreciate any suggestions for greater realism or a link if anything similar has been done (I could not find anything on Google). Thank you.

  - (id)initWithFrame:(CGRect)frame {
    if ((self = [super initWithFrame:frame])) {

        self.backgroundColor = [UIColor whiteColor];

        v = [[UIView alloc] initWithFrame:CGRectMake(140, 140, 60, 60)];
        v.backgroundColor = [UIColor blueColor];

        [self addSubview:v];
        [self animate];

    }
    return self;
}

- (void)animate {

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationCurve:UIViewAnimationCurveLinear];
    [UIView setAnimationDuration:0.2];
    [UIView setAnimationDelegate:self];
    [UIView setAnimationDidStopSelector:@selector(popStep1Complete)];
    v.frame = CGRectMake(90, 90, 140, 140);
    [UIView commitAnimations];
}

- (void)popStep1Complete {

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationCurve:UIViewAnimationCurveLinear];
    [UIView setAnimationDuration:0.15];
    [UIView setAnimationDelegate:self];
    [UIView setAnimationDidStopSelector:@selector(popStep2Complete)];
    v.frame = CGRectMake(110, 110, 100, 100);
    [UIView commitAnimations];
}

- (void)popStep2Complete {

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationCurve:UIViewAnimationCurveLinear];
    [UIView setAnimationDuration:0.15];
    v.frame = CGRectMake(100, 100, 120, 120);
    [UIView commitAnimations];
}