用Web服务连接Estimote信标

Question

我是Android新手，我正在尝试使用Estimote Beacons构建一个android应用程序。我想从web服务获得动态通知。为此，我在Android应用程序类中添加了网络调用，这样它就可以在后台连续调用。我面临的问题是，网络调用有时会触发，有时不会。从Application类进行网络调用是一种礼仪吗？我该怎么做呢？下面我附上了Application类代码。

    public class AppController extends Application {
public static final String TAG = AppController.class.getSimpleName();
private boolean beaconNotificationsEnabled = false;
SharedPreferences sharedPreferences;
Editor editor;
private RequestQueue mRequestQueue;
String uuid_beacon;
String displayNotification;
private BeaconManager beaconManager;
private static AppController mInstance;

String authLoginValue;
String displayMinorNO;
String uuid;
String majorno;
String minorno;
String notify;
String urlforimage;

@Override
public void onCreate() {
    super.onCreate();

    sharedPreferences = getApplicationContext().getSharedPreferences("Reg", 0);
    editor = sharedPreferences.edit();
    mInstance = this;
    authLoginValue = sharedPreferences.getString("AuthTokenLogin", "");
    System.out.println("LOGIN FROM APP CONTROLLER:"+authLoginValue);

    beaconManager = new BeaconManager(getApplicationContext());
    beaconManager.setMonitoringListener(new BeaconManager.MonitoringListener() {
        @Override
        public void onEnteredRegion(Region region, List<Beacon> list) {
            System.out.println("ENETERD");

            for (Beacon beacon : list) {
                uuid = beacon.getProximityUUID().toString();
                majorno = String.valueOf(beacon.getMajor());
                minorno = String.valueOf(beacon.getMinor());
                sendUUID(uuid, authLoginValue, majorno, minorno);

            }
            displayNotification = sharedPreferences.getString("Notification", "");

            showNotification(displayNotification, "Click here to continue");
        }
        @Override
        public void onExitedRegion(Region region) {
            // could add an "exit" notification too if you want (-:
            showNotification(
                    "THANKS FOR VISITING",
                    "Come back again"
            );
        }
    });
    beaconManager.connect(new BeaconManager.ServiceReadyCallback() {
        @Override
        public void onServiceReady() {
            beaconManager.startMonitoring(new Region("monitored region",
                    UUID.fromString("B9407F30-F5F8-466E-AFF9-25556B57FE6D"), null, null));
        }
    });

}
public static synchronized AppController getInstance() {
    return mInstance;
}
public RequestQueue getRequestQueue() {
    if (mRequestQueue == null) {
        mRequestQueue = Volley.newRequestQueue(getApplicationContext());
    }

    return mRequestQueue;
}

public <T> void addToRequestQueue(Request<T> req, String tag) {
    req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
    getRequestQueue().add(req);
}

public <T> void addToRequestQueue(Request<T> req) {
    req.setTag(TAG);
    getRequestQueue().add(req);
}

public void cancelPendingRequests(Object tag) {
    if (mRequestQueue != null) {
        mRequestQueue.cancelAll(tag);
    }
}

public void showNotification(String title, String message) {
    Intent notifyIntent = new Intent(this, MainActivity.class);
    notifyIntent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
    PendingIntent pendingIntent = PendingIntent.getActivities(this, 0,
            new Intent[]{notifyIntent}, PendingIntent.FLAG_UPDATE_CURRENT);
    Notification notification = new Notification.Builder(this)
            .setSmallIcon(R.drawable.logo_7edge)
            .setContentTitle(title)
            .setContentText(message)
            .setAutoCancel(true)
            .setContentIntent(pendingIntent)
            .build();
    notification.defaults |= Notification.DEFAULT_SOUND;
    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    notificationManager.notify(1, notification);
}

public void sendUUID(final String uuid, final String authTokenLoginValue,final String majorno, final String minorno) {

    // Tag used to cancel the request
    String tag_string_req = "req_register";

    StringRequest strReq = new StringRequest(Request.Method.POST,
            AppConfig.URL_UUID, new Response.Listener<String>() {

        @Override
        public void onResponse(String response) {
            Log.d(TAG, "Notification Response: " + response.toString());
            try {
                JSONObject jObj = new JSONObject(response);
                String notifyresponse = jObj.getString("notification");

                JSONObject objecttonotify = new JSONObject(notifyresponse);

                notify = objecttonotify.getString("notification");
                urlforimage = objecttonotify.getString("url");

                System.out.println("URL:"+urlforimage);


                editor.putString("Notification", notify);
                editor.putString("image_url", urlforimage);
                editor.commit();


                Log.d(TAG, "Notification1" + notify);

                String msg =jObj.get("status").toString();



                if(msg.equals("ok"))
                {
                    String SuccessMsg = jObj.getString("message");
                    //Toast.makeText(getApplicationContext(), SuccessMsg, Toast.LENGTH_LONG).show();
                }
                else if(msg.equals("error")) {
                    String errorMsg = jObj.getString("message");
                    Toast.makeText(getApplicationContext(), errorMsg, Toast.LENGTH_LONG).show();
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

        }
    }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            Log.e(TAG, "Notification Error: " + error.getMessage());
            Toast.makeText(getApplicationContext(),
                    error.getMessage(), Toast.LENGTH_LONG).show();

        }
    }) {

        @Override
        protected Map<String, String> getParams() {
            // Posting params to register url
            Map<String, String> params = new HashMap<String, String>();
            params.put("uuid", uuid);
            params.put("authtoken", authTokenLoginValue);
            params.put("major_no", majorno);
            params.put("minor_no", minorno);

            return params;
        }

    };

    // Adding request to request queue
    AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}

Answer 1

如果你的代码像你所说的那样间歇性地成功进行网络调用，那么在我看来，根据你的web/服务器参数，代码似乎是正常工作的。因此，我假设通过截击进行连接的尝试是合理的。

但是，从您发布的代码来看，您没有指明您已检查设备是否已启用BT、已启用网络和Internet可用性。为了判断您的代码是否一致地工作，它的良好实践是，首先确保移动设备已启用BT、启用网络并可访问Internet。下面的代码片段适用于我。当然包括所有必要的用户权限：

蓝牙已启用：

BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (!mBluetoothAdapter.isEnabled()) {
mBluetoothAdapter.enable();

网络和互联网：

public static NetworkInfo getNetworkInfo(Context context){
    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    return cm.getActiveNetworkInfo();
}


//Check if there is any connectivity

public static boolean isConnected(Context context){
    NetworkInfo info = Utilities.getNetworkInfo(context);
    return (info != null && info.isConnected());
}


 // Check if there is any connectivity to a Wifi network

public static boolean isConnectedWifi(Context context){
    NetworkInfo info = Utilities.getNetworkInfo(context);
    return (info != null && info.isConnected() && info.getType() == ConnectivityManager.TYPE_WIFI);
}


// Check if there is any connectivity to a mobile network

public static boolean isConnectedMobile(Context context){
    NetworkInfo info = Utilities.getNetworkInfo(context);
    return (info != null && info.isConnected() && info.getType() == ConnectivityManager.TYPE_MOBILE);
}

// TEST FOR INTERNET ACCESS / WEBSITE AVAILABLE

public static boolean isInternetOn() {

    String command = "ping -c1 -w3 google.com";

    // TODO progress bar while checking for internet.

    try {
        return (Runtime.getRuntime().exec(command).waitFor() == 0);
    } catch (InterruptedException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    return false;
} //EO Internet ping

希望能有所帮助。