需要权限的生命周期感知组件

Question

假设我有一个组件需要根据 activity 的生命周期进行初始化和销毁​​。但是，此组件需要先获得用户的许可。最好的方法是什么？

我是否必须在两个不同的位置订阅同一个观察者，或者有没有代码重复的更好方法？

Answer 1

您可以实现生命周期感知class 封装权限敏感工作：

class MyLifecycleAware {

    private var blObject: Any? = null

    /**
    * Manually call this method when permission granted
    */
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    fun init() = withPermission {
        // code will be invoked only if permission was granted
        blObject = TODO("Initialize business logic")
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    fun destroy() {
        blObject?.destroy()
        blObject = null
    }

    /**
     * Wrap any permission sensitive actions with this check 
     */
    private inline fun withPermission(action: () -> Unit) {
        val permissionGranted = TODO("Check permission granted")
        if (permissionGranted)
            action()
    }
}