android-intent - 如何在前台应用程序打开（/关闭）wifi时通知？

Question

我正在尝试在后台运行一个应用程序，它会告诉我 wifi 的状态何时被修改；

public class BackgroundJobs extends Service {

public int onStartCommand(Intent intent, int flags, int startId) {
    Log.i("BACKJOBS", "here we are");
    wifiInfo wifiHandler = new wifiInfo(this);
    // wifistatus checks if wifi is on or off, returning a boolean
    if(wifiHandler.wifiStatus())
        Log.i("BACKJOBS", "WIFI ON");
    else
        Log.i("BACKJOBS", "WIFI OFF");
    return Service.START_NOT_STICKY;
}

@Override
public IBinder onBind(Intent intent) {
    //TODO for communication return IBinder implementation
    return null;
}
}

在我的 MainActivity 中，我按如下方式启动服务：

startService(new Intent(this, BackgroundJobs.class));

在 AndroidManifest.xml 中：

<service android:name=".gestioneServizi.BackgroundJobs"/>

我启动我的应用程序，按下主页按钮回到家，打开或关闭 wifi，但我没有看到日志“BACKJOBS”。

我是误解了什么还是我使用了错误的方法？

Answer 1

对于这种情况，您应该使用 BroadcastReceiver。

显现：

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

接收者：

 public class ConnectionReceiver extends BroadcastReceiver {
   private static String lastActiveNetworkName = null;
   private ConnectivityManager connectivityManager;
   private NetworkInfo wifiInfo;

   @Override
   public void onReceive(final Context context, Intent intent) {
    try {
      connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
      wifiInfo = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
      NetworkInfo network = connectivityManager.getActiveNetworkInfo();

     if (network != null) {
            String networkName = network.getTypeName();
            if (!networkName.equals(lastActiveNetworkName)) {
                lastActiveNetworkName = networkName;
            } else {
                Log.d(TAG, "Network equals lastnetwork:" + lastActiveNetworkName);
            }
        }

        if (intent.getAction().equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)) {
            NetworkInfo networkInfo = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);

            if (networkInfo.isConnected()) {
                Log.d(TAG, "Wifi is connected: " + String.valueOf(networkInfo));
            }
        } else if (intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
            NetworkInfo networkInfo = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
            if (networkInfo.getType() == ConnectivityManager.TYPE_WIFI && !networkInfo.isConnected()) {
                Log.d(TAG, "Wifi is disconnected: " + String.valueOf(networkInfo));
            }
        }
}