registerDefaultNetworkCallback和registerNetworkCallback之间的区别 [英] Difference between registerDefaultNetworkCallback and registerNetworkCallback

问题描述

我遇到了 registerDefaultNetworkCallback 和解决方案

据我了解，registerDefaultNetworkCallback和registerNetworkCallback之间的区别仅基于自定义.
<令人惊讶的是，registerDefaultNetworkCallback作为默认网络侦听器工作，而registerNetworkCallback则更具可配置性.例如:

    val connectivityManager = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager

    val builder = NetworkRequest.Builder()
    builder.addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)

    val networkRequest = builder.build()
    connectivityManager.registerNetworkCallback(networkRequest, 
    object : ConnectivityManager.NetworkCallback () {
        override fun onAvailable(network: Network?) {
            super.onAvailable(network)
            Log.i("Test", "Network Available")
        }

        override fun onLost(network: Network?) {
            super.onLost(network)
            Log.i("Test", "Connection lost")
        }
    })

仅当用户连接到蜂窝网络(通过连接WiFi不会记录任何内容)时，才会调用onAvailable.从蜂窝网络断开连接时，onLost也是一样.

如果我们这样做:

    connectivityManager.registerDefaultNetworkCallback(object  : ConnectivityManager.NetworkCallback() {
        override fun onAvailable(network: Network?) {
            super.onAvailable(network)
            Log.i("Test", "Default -> Network Available")
        }

        override fun onLost(network: Network?) {
            super.onLost(network)
            Log.i("Test", "Default -> Connection lost")
        }
    })

当用户与网络连接(或断开连接)(可以是WiFi或蜂窝网络)时，这两个功能均作为默认回调.

这些只是一些非常基本的示例.当然，通过设置capability或transportType，NetworkRequest可以具有许多配置.您可以在 NetworkRequest 的官方文档中阅读有关这些内容的更多信息. >

I came across registerDefaultNetworkCallback and registerNetworkCallback while updating my Android app for API 28.

Having reviewed the documentation, I cannot find the difference between registering a network callback and registering a default network callback.

When will one use which?

Thanks in advance :)

解决方案

As far as I understood, the difference between registerDefaultNetworkCallback and registerNetworkCallback it's only based on customisation.
registerDefaultNetworkCallback works (surprisingly) as a default network listener, while registerNetworkCallback it's more configurable. For example:

    val connectivityManager = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager

    val builder = NetworkRequest.Builder()
    builder.addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)

    val networkRequest = builder.build()
    connectivityManager.registerNetworkCallback(networkRequest, 
    object : ConnectivityManager.NetworkCallback () {
        override fun onAvailable(network: Network?) {
            super.onAvailable(network)
            Log.i("Test", "Network Available")
        }

        override fun onLost(network: Network?) {
            super.onLost(network)
            Log.i("Test", "Connection lost")
        }
    })

Here onAvailable will be called only if the user connects to a cellular network (by connecting to WiFi it won't log anything). The same does onLost when disconnecting from cellular network.

If we do it like this:

    connectivityManager.registerDefaultNetworkCallback(object  : ConnectivityManager.NetworkCallback() {
        override fun onAvailable(network: Network?) {
            super.onAvailable(network)
            Log.i("Test", "Default -> Network Available")
        }

        override fun onLost(network: Network?) {
            super.onLost(network)
            Log.i("Test", "Default -> Connection lost")
        }
    })

Both functions work as default callbacks when the user is connecting (or disconnecting) to/from a network (it can be either WiFi or cellular).

These are just some very basic examples. Of course NetworkRequest can have a lot of configurations by setting its capability or transportType. You can read more about these in the official documentation of NetworkRequest.

这篇关于registerDefaultNetworkCallback和registerNetworkCallback之间的区别的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！