如何从自定义视图访问宿主片段的生命周期范围? [英] How to access lifecycleScope of the host fragment from a custom view?

问题描述

我需要在自定义视图中使用协程.看完这个谈话后，我相信我最好的选择是使用 lifecycleScope 作为协程范围，这样当生命周期所有者被销毁时它会自动取消.

I need to use coroutines inside a custom view. After watching this talk, I believe my best option is to use lifecycleScope as the coroutine scope, so that it will be automatically cancelled when lifecycleowner is destroyed.

但是我似乎无法访问自定义视图中的生命周期范围.根据文档，我们可以从lifecycle 对象为 lifecycle.coroutineScope 或来自 lifecycleOwner 为 lifecycleOwner.lifecycleScope.但是自定义视图不是生命周期所有者.那么我可以以某种方式访问​​片段的生命周期范围吗?或者如果我不能，我应该使用哪个协程上下文?

However I don't seem to have access to lifecycleScope inside the custom view. According to documentation, we can either have access to it from a lifecycle object as lifecycle.coroutineScopeor from a lifecycleOwner as lifecycleOwner.lifecycleScope. But custom view is not a lifecycle owner. So can I have access to lifecycleScope of the fragment somehow? Or if I can't, which coroutine context should I use instead?

推荐答案

我通过实施 LifecycleObserver 接口.这在 Udacity 上的 免费课程的第 4 课中得到了很好的解释 如何使用 LifecycleObserver 接口制作生命周期感知组件.

I solved this by implementing LifecycleObserver interface. It was very well explained in lesson 4 of this free course on Udacity how to make lifecycle aware components with LifecycleObserver interface.

我在片段内部和自定义视图中注册了片段的生命周期，在获取生命周期的同时，我使用生命周期来获取生命周期范围.

I registered the lifecycle of the fragment inside the fragment and inside the custom view, while I get the lifecycle, I used the lifecycle to grap lifecycleScope.

//Inside custom view
fun registerLifecycleOwner(lifecycle: Lifecycle){
    lifecycle.addObserver(this)
    scope = lifecycle.coroutineScope
}

//Inside fragment
binding.myCustomView.registerLifecycleOwner(lifecycle)

然后在自定义视图中，我像这样使用它:

Then inside the custom view, I used it like:

scope.launch{ 
    //Do work
}

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