禁用动画

CALayer 属性动画默认启用。如果不希望这样，可以按如下方式禁用它们。

迅速

CATransaction.begin()
CATransaction.setDisableActions(true)

// change layer properties that you don't want to animate

CATransaction.commit()

Objective-C

[CATransaction begin];
[CATransaction setDisableActions:YES];

// change layer properties that you don't want to animate

[CATransaction commit];