您是否尝试了<条码>代号财产? 如果在任何地方增加你的一层。

if (layer.superlayer == parentLayer) {
    ...
} else {
    ...
}

意见.layer.sublayers 给你一系列次层,看看你是否添加了你的一层,可以做些什么,如观点、继器、计数以及一层计达到你预期的外观。

if (view.layer.sublayers.count  < 3) {
//add layer
}else{
// do nothing because the layer has already been added.
}

你们还可以审查子站各层,以更好地确定你所期待的层次。 由于它们是特性,你应当能够与阵列中的每一层进行比较,以了解你所期望的层次是否得到增加。

我需要检查一下,看看一位梯度律师是否是另一个观点的副手。 这是那里唯一的一层,因此我不得不检查任何其他东西。 以上答复对我来说是徒劳的。

I came across this answer and even though it was used for a different reason it was an easy way to check if the gradientLayer was a child of another view s layer property (the parentLayer) and it works fine for me:

if let _ = (yourParentView.layer.sublayers?.compactMap { $0 as? CAGradientLayer })?.first {

    print("the gradientLayer IS already a subLayer of this parentView s layer property")
} else {

    print("the gradientLayer IS NOT a subLayer of this parentView s layer property")
}

页: 1

if view.layer.sublayers == nil {

    // add Sublayer

}

• /检查CALayer Contains Sublayer(shpapelayer/textlayer)

                             if myShapeLayer.sublayers?.count>0
                             {
                                 var arr:NSArray? = myShapeLayer.sublayers as NSArray
                                 var i:Int=0
                                 for i in 0..<arr!.count
                                 {
                                     var a: AnyObject = arr!.objectAtIndex(i)
                                     if a.isKindOfClass(CAShapeLayer) || a.isKindOfClass(CATextLayer)
                                     {
                                         if a.isKindOfClass(CAShapeLayer)
                                         {
                                             a = a as! CAShapeLayer
  
                                             if CGPathContainsPoint(a.path, nil, pointOfCircle, true)
                                             {
                                                 NSLog("contains shape layer")
  
                                             }
                                             else
                                             {
                                                 NSLog("not  contains shape layer")
  
                                             }
                                         }
                                         if a.isKindOfClass(CATextLayer)
                                         {
                                             a = a as! CATextLayer
                                             var fr:CGRect = a.frame as CGRect
                                             if CGRectContainsPoint(fr, pointOfCircle)
                                             {
                                                 NSLog("contains textlayer")
  
                                             }
                                             else
                                             {
                                                 NSLog("not contains textlayer")
  
                                             }
                                         }
  
                                     }
                                 }
                             }