你如何實現UIAccessibility協議？

Question

的 「輔助功能編程指南對於iOS」 規定：

Another way is to implement the isAccessibilityElement method of the UIAccessibility protocol in the implementation of your custom subclass. The following code snippet shows how to do this:

但是當我這樣做，如下面的代碼：

class UITextLayerLabel : UIView, UIAccessibility { 

的XCode返回我這個錯誤：

[...] Use of undeclared type 'UIAccessibility' 

我錯過了什麼？具體的進口？該協議仍可用於iOS 10/XCode8嗎？

Answer 1

如指出here，UIAccessibility是一個非正式協議。有關非正式協議與正式協議之間的區別，請參見here。基本上沒有類型叫UIAccessibility。實際上，UIView已經符合UIAccessibility。要使您的自定義視圖可訪問，只需覆蓋以accessibility開頭的屬性和方法。

所以，當你需要實現UIAccessibility？如前所述here，

You can use UIAccessibilityElement to provide information about an icon or text image is not automatically accessible because it does not inherit from UIView (or UIControl). A view that contains such nonview items creates an instance of UIAccessibilityElement to represent each item that needs to be accessible.