android11 监听网络变动 代码或demo

以下是一个使用BroadcastReceiver的示例程序，用于监听网络状态变化：

1.添加权限：

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />

2.创建BroadcastReceiver：

public class NetworkChangeReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {
            //网络已连接
        } else {
            //网络未连接
        }
    }
}

3.在AndroidManifest.xml中注册BroadcastReceiver：

<receiver android:name=".NetworkChangeReceiver">
    <intent-filter>
        <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
        <action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
    </intent-filter>
</receiver>

4.在Activity中启动BroadcastReceiver：

NetworkChangeReceiver networkChangeReceiver = new NetworkChangeReceiver();
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
intentFilter.addAction(WifiManager.WIFI_STATE_CHANGED_ACTION);
registerReceiver(networkChangeReceiver, intentFilter);

5.在Activity中注销BroadcastReceiver：

unregisterReceiver(networkChangeReceiver);