立即更新CALayer子图层

Question

I have UIView which has the following structure:

UIView
  |- layer (CALayer)
    |- depthLayer (CALayer)
    |- bodyLayer (CALayer)

For layer I set needsDisplayOnBoundsChange = true. When I change size of UIView, layer redraws immediately. But their sublayers updates with some delay (on the next draw iteration). How to sync draw of layers with sublayers depthLayer and bodyLayer ?

UIView:

override func drawRect(rect: CGRect) {
    bodyLayer.frame = rect
    depthLayer.frame = CGRectOffset(rect, 0, 5)
}

Answer 1

The delays you see in your CALayer's frames are cause because the Animations -> when you making a change to the CALayer's appearance It tries to animate it (and it often successes -> well this is why they called animations layers).

To disable this behavior (animations) you should call the disable transactions like this:

CATransaction.setValue(kCFBooleanTrue, forKey:kCATransactionDisableActions) //..Make Change to the frames here CATransaction.commit()

Also I don't know wether you have a real need to override the drawRect for this matter -> if you set the UIView's Frame via setFrame: method, it is better to override the setFrame: method itself and adjust the Frames of subLayers there.

Lot of Luck!