android销毁时有视图回调吗?

android is there any view callback when it's destroyed?

我有一个自定义视图组件。我在片段或 activity 中使用了它。我想知道从fragment/activity?

销毁时是否有回调

View 没有回调(finalize() 除外,但我认为这不是您所要求的)。视图从屏幕上移开时有 onDetachedFromWindow(),但这与它被销毁无关——它可以再次附加,这将调用 onAttachedToWindow().

片段有onDestroyView(),可能对你更有用。 Activity 没有等效的方法,但您可以使用 onDestroy(),只要您知道如果系统决定意外终止您的应用程序,它可能永远不会被调用。

感谢 Karakuri 的回答,可选的解决方案(使用简单的回调)

Note

view OnLayoutChangeListener not called before view detached from window

   view.listener = object :OnViewAttachedChangeListener{
                    override fun onAttachedFromWindow(view: View, isAttached: Boolean) {
    
                    }
                }

添加用于跟踪附件状态的简单回调。

   internal class AttachedView(context: Context): View(context){

        internal var listener: OnViewAttachedChangeListener?= null
            get() = field

        override fun onDetachedFromWindow() {
            super.onDetachedFromWindow()
            notifyOnAttachedToWindow(false)
        }

        override fun onAttachedToWindow() {
            super.onAttachedToWindow()
            notifyOnAttachedToWindow(true)
        }

        private fun notifyOnAttachedToWindow(isAttached: Boolean){
            listener?.onAttachedFromWindow(this, isAttached)
        }
    }

    internal interface OnViewAttachedChangeListener{
        fun onAttachedFromWindow(view: View, isAttached: Boolean)
    }