android - 自动连接到android中的wifi网络？

Question

我正在开发一个应用程序，只要 wifi 打开，后台应用程序就应该连接到网络(如果它之前连接过网络)？我可以为此目的使用广播接收器吗？

Answer 1

为了接收连接变化的Broadcast，你可以这样收听:

在 AndroidManifest.xml 中注册您的接收器

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

然后在BroadcastReceiver类

public class NetworkCheckReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
                Log.d("NetworkCheckReceiver", "NetworkCheckReceiver invoked...");


                boolean noConnectivity = intent.getBooleanExtra(
                        ConnectivityManager.EXTRA_NO_CONNECTIVITY, false);

                if (!noConnectivity) {
                    Log.d("NetworkCheckReceiver", "connected");
                    WifiConfiguration wifiConfig = new WifiConfiguration();
                    wifiConfig.SSID = String.format("\"%s\"", networkSSID);
                    wifiConfig.preSharedKey = String.format("\"%s\"", networkKey);
                    WifiManager wifiManager = (WifiManager) mContext.getSystemService(Context.WIFI_SERVICE);

                    int netId = wifiManager.addNetwork(wifiConfig);
                    wifiManager.disconnect();
                    wifiManager.enableNetwork(netId, true);
                    wifiManager.reconnect();
                }
                else{
                    Log.d("NetworkCheckReceiver", "disconnected");
                }
            }
        }
 }

当然，不要忘记添加所需的权限

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