网络状态监听 → ConnectivityManager + Flow

老写法

public class NetworkReceiver extends BroadcastReceiver {
@Override
public void onReceive {
ConnectivityManager cm =
context.getSystemService;NetworkInfo info = cm.getActiveNetworkInfo;其实，boolean isConnected = info!= null && info.isConnected;updateNetworkState;其实，}
}
// 注册
IntentFilter filter = new IntentFilter;registerReceiver,filter);

问题在哪里

• API过时风险：NetworkInfo已被废弃，新版本可能不再支持
• 生命周期管理复杂：必须手动注册/解注册广播，容易导致内存泄漏或崩溃
• 功能有限：只能获取"是否连接"，无法直接判断具体网络类型
• 性能开销：广播机制效率较低，频繁触发可能影响性能
• Android Q+兼容性：从Android Q开始。后台应用对CONNECTIVITY_ACTION的监听受到严格限制

新写法✨ 推荐方法 ✨

class NetworkMonitor {
private val connectivityManager =
context.getSystemService as ConnectivityManager
val isConnected: Flow = callbackFlow {
val callback = object : ConnectivityManager.NetworkCallback {
override fun onAvailable {
trySend
}
override fun onLost {
trySend
}
}
val request = NetworkRequest.Builder
.addCapability
.build
connectivityManager.registerNetworkCallback
// 发送当前状态
val currentNetwork = connectivityManager.activeNetwork
val capabilities = connectivityManager.getNetworkCapabilities
trySend == true)
awaitClose {
connectivityManager.unregisterNetworkCallback
}
}
}
// 使用
viewModelScope.launch {
networkMonitor.isConnected.collect { connected ->
tvStatus.text = if "已连接" else "无网络"
}
}

关键优势解析🔍为什么要换？痛点方法，按理说，

1. 生命周期自动管理：awaitClose{}保证Flow取消时自动解注册回调。解决掉内存泄漏问题，不再需要在Activity/Fragment的onDestroy中手动清理！🎉🎉🎉

 // 唯一支持VPN且有上传能力的网络
builder.addTransportType
.addCapability

一句话注意事项☝️