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POHow can I create a custom "pin-drop" animation using MKAnnotationView?
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copied!<p>I have an instance of <code>MKMapView</code> and would like to use custom annotation icons instead of the standard pin icons supplied by MKPinAnnotationView. So, I've setup a subclass of MKAnnotationView called CustomMapAnnotation and am overriding <code>-(void)drawRect:</code> to draw a CGImage. This works.</p> <p>The trouble comes when I try to replicate the <code>.animatesDrop</code> functionality supplied by MKPinAnnotationView; I would love for my icons to appear gradually, dropped from above and in left-to-right order, when the annotations are added to the <code>MKMapView</code> instance.</p> <p>Here is -(void)drawRect: for CustomMapAnnotation, which works when you just draw the UIImage (which is what the 2nd line does):</p> <pre><code>- (void)drawRect:(CGRect)rect { [super drawRect:rect]; [((Incident *)self.annotation).smallIcon drawInRect:rect]; if (newAnnotation) { [self animateDrop]; newAnnotation = NO; } } </code></pre> <p>The trouble comes when you add the <code>animateDrop</code> method:</p> <pre><code>-(void)animateDrop { CGContextRef myContext = UIGraphicsGetCurrentContext(); CGPoint finalPos = self.center; CGPoint startPos = CGPointMake(self.center.x, self.center.y-480.0); self.layer.position = startPos; CABasicAnimation *theAnimation; theAnimation=[CABasicAnimation animationWithKeyPath:@"position"]; theAnimation.fromValue=[NSValue valueWithCGPoint:startPos]; theAnimation.toValue=[NSValue valueWithCGPoint:finalPos]; theAnimation.removedOnCompletion = NO; theAnimation.fillMode = kCAFillModeForwards; theAnimation.delegate = self; theAnimation.beginTime = 5.0 * (self.center.x/320.0); theAnimation.duration = 1.0; [self.layer addAnimation:theAnimation forKey:@""]; } </code></pre> <p>It just doesn't work, and there could be a lot of reasons why. I won't get into all of them now. The main thing I am wanting to know is if the approach is sound at all, or if I should try something entirely different.</p> <p>I tried also to package up the whole thing into an animation transaction so that the beginTime parameter might actually work; this seemed to not do anything at all. I don't know if this is because I am missing some key point or whether it's because MapKit is trashing my animations somehow.</p> <pre><code> // Does nothing [CATransaction begin]; [map addAnnotations:list]; [CATransaction commit]; </code></pre> <p>If anyone has any experience with animated MKMapAnnotations like this, I'd love some hints, otherwise if you can offer CAAnimation advice on the approach, that'd be great too.</p>

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