获取空 Volley 参考

Question

我在 logcat 中的空引用上收到 Volley addId.add(request) 在发布了填充了 gcm regID 的字符串后请问这里有什么问题？我发布的布尔值也是真的吗？我的意思是 getRegId();仅适用于第一个运行?

public class MainActivity extends AppCompatActivity  {



    String projectNumber = "*********";
    GoogleCloudMessaging gcm;
    String regId ="";
    String TAG = "Register Service";
    RequestQueue addId;
    String url = "***************";
    String version = BuildConfig.VERSION_NAME;
   boolean firstRun = true;
    double d = Double.parseDouble(version);



    @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        isNetworkConnected();

        SharedPreferences prefs = getSharedPreferences("PREFS_NAME", 0);
        firstRun = prefs.getBoolean("FIRST_RUN", true);




        if(firstRun){

            prefs = getSharedPreferences("PREFS_NAME", 0);
            SharedPreferences.Editor editor = prefs.edit();
            editor.putBoolean("FIRST_RUN",false);
            editor.apply();
            getRegId();


    }

...........


    public void sendId() {

        StringRequest request = new StringRequest(Request.Method.POST, url,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {


                        Log.i("The registration", "success sent");
                    }
                }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {

                Log.i("The registration", "error sent");


            }
        }) {


            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<String, String>();
                params.put("gcmregid", regId);

                return params;
            }


        };
        addId.add(request);

    }

    public void getRegId() {
        new AsyncTask<Void, Void, String>() {

            @Override
            protected String doInBackground(Void... params) {

                String msg = "";

                try {
                    if (gcm == null) {
                        InstanceID instanceID = InstanceID.getInstance(getApplicationContext());
                        regId = instanceID.getToken(projectNumber, GoogleCloudMessaging.INSTANCE_ID_SCOPE);

                        msg = "Device registration, registration ID=" + regId;
                        Log.i(TAG, msg);
                        if (regId.isEmpty()){
                            instanceID = InstanceID.getInstance(getApplicationContext());
                            regId = instanceID.getToken(projectNumber, GoogleCloudMessaging.INSTANCE_ID_SCOPE);

                        }
                    }

                } catch (IOException e) {
                    e.printStackTrace();
                    msg = "Error :" + e.getMessage();
                }
                return msg;
            }

            @Override
            protected void onPostExecute(String s) {
                sendId();
            }
        }.execute(null, null, null);

    }

    private boolean isNetworkConnected() {
                ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
                NetworkInfo ni = cm.getActiveNetworkInfo();
                if (ni == null) {
                    Toast.makeText(getApplicationContext(), "No Network", Toast.LENGTH_SHORT).show();
                    return false;
                }
                return true;
            }



}

=========================================== ======================

Answer 1

您没有在任何地方初始化 addId 对象。你不应该做 RequestQueue addId = new RequestQueue(); 而不是 RequestQueue addId; 吗？

Answer 2

添加这一行，

 addId = new RequestQueue();

这一行之前

addId.add(request);

您没有初始化 RequestQueue 对象。

获取空 Volley 参考

Get null Volley reference

java

android

google-cloud-messaging

android-volley