Disable animation when moving CALayers

问题:

The following code animates the movement, even though I didn't use beginAnimations:context. How do I get it to move without animating? This is a new iphone view project, and these are the only updates to it.

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
    [super viewDidLoad];

    sublayer = [CALayer new];
    sublayer.backgroundColor = [[UIColor redColor] CGColor];
    sublayer.frame = CGRectMake(0, 0, 100, 100);

    [self.view.layer addSublayer:sublayer];
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    sublayer.position = [[touches anyObject] locationInView:self.view];
}

回答1:

The simplest way to do it is to override the animation duration by putting the position code into a transaction:

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    [CATransaction begin];
    [CATransaction setAnimationDuration:0];
    sublayer.position = [[touches anyObject] locationInView:self.view];
    [CATransaction commit];
}

回答2:

More simplest way:

sublayer.position = [[touches anyObject] locationInView:self.view];
[sublayer removeAnimationForKey:@"position"];