nicht auflösen kann Methode 'addToRequestQueque (com.android.volley.toolbox.StringRequest, java.lang.String)'

Question

Im gehend, eine Datenbank in PHP

meine sql mit Android Studio zu machen, aber dieser Fehler ist auf dem Weg

//Adding request to request queue 
      AndroidLoginController.getInstance(); 

      addToRequestQueue(strReq, tag_string_req); 
     } 

I erhalten der Fehler nicht Methode 'addToRequestQueque (com.android.volley.toolbox.StringRequest, java.lang.String)'

import android.app.ProgressDialog; 
import android.content.Intent; 
import android.net.Uri; 
import android.os.Bundle; 
import android.support.v7.app.AppCompatActivity; 
import android.util.Log; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 
import android.widget.Toast; 

import com.android.volley.Request; 
import com.android.volley.Response; 
import com.android.volley.VolleyError; 

import com.android.volley.toolbox.StringRequest; 
import com.example.pjsr.brnp.MainActivity; 
import com.google.android.gms.appindexing.Action; 
import com.google.android.gms.appindexing.AppIndex; 
import com.google.android.gms.appindexing.Thing; 
import com.google.android.gms.common.api.GoogleApiClient; 

import org.json.JSONException; 
import org.json.JSONObject; 

import java.util.HashMap; 
import java.util.Map; 

import prefs.UserInfo; 
import prefs.UserSession; 


public class Login extends AppCompatActivity implements View.OnClickListener { 
    private static final String TAG = Login.class.getSimpleName(); 
    private EditText email, password; 
    private Button login; 
    private TextView signup; 
    private ProgressDialog progressDialog; 
    private UserSession session; 
    private UserInfo userInfo; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_login); 

     email = (EditText) findViewById(R.id.email); 
     password = (EditText) findViewById(R.id.password); 
     login = (Button) findViewById(R.id.login); 
     signup = (TextView) findViewById(R.id.open_signup); 
     progressDialog = new ProgressDialog(this); 


     session = new UserSession(this); 
     userInfo = new UserInfo(this); 

     if (session.isUserLoggedin()) { 
      startActivity(new Intent(this, MainActivity.class)); 
      finish(); 

     } 

     login.setOnClickListener(this); 
     signup.setOnClickListener(this); 

    } 

    private void login(final String email, final String password) { 
     //Tag used to cancel the request 
     String tag_string_req = "req_login"; 
     progressDialog.setMessage("Logging in...."); 
     progressDialog.show(); 

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

      @Override 
      public void onResponse(String response) { 
       Log.d(TAG, "Login Response: " + response.toString()); 

       try { 
        JSONObject jObj = new JSONObject(response); 
        boolean error = jObj.getBoolean("error"); 

        //check for error node in json 
        if (!error) { 
         //now store the user in SQLite 
         JSONObject user = jObj.getJSONObject("user"); 
         String uName = user.getString("username"); 
         String email = user.getString("email"); 

         //Inserting row in users table 
         userInfo.setEmail(email); 
         userInfo.setUsername(uName); 
         session.setLoggedin(true); 

         startActivity(new Intent(Login.this, MainActivity.class)); 
         finish(); 
        } else { 
         //error in login, get the error message 
         String errorMsg = jObj.getString("error_msg"); 
         toast(errorMsg); 
        } 
       } catch (JSONException e) { 
        //json error 
        e.printStackTrace(); 
        toast("Json error: " + e.getMessage()); 

       } 
      } 

     }, new Response.ErrorListener() { 

      @Override 
      public void onErrorResponse(VolleyError error) { 
       Log.e(TAG, "Login Error: " + error.getMessage()); 
       toast("Unknown Error occured"); 
       progressDialog.hide(); 
      } 

     }) { 
      @Override 
      protected Map<String, String> getParams() { 
       //Posting parameters to login url 
       Map<String, String> params = new HashMap<>(); 
       params.put("email", email); 
       params.put("password", password); 

       return params; 

      } 
     }; 


//Adding request to request queue 
     AndroidLoginController.getInstance(); 

     addToRequestQueue(strReq, tag_string_req); 
    } 

    private void toast(String x) { 
     Toast.makeText(this, x, Toast.LENGTH_SHORT).show(); 
    } 

    @Override 
    public void onClick(View v) { 
     switch (v.getId()) { 
      case R.id.login: 
       String uName = email.getText().toString().trim(); 
       String pass = password.getText().toString().trim(); 

       login(uName, pass); 
       break; 
      case R.id.open_signup: 
       startActivity(new Intent(this, SignUp.class)); 
       break; 

     } 
    } 


    /** 
    * ATTENTION: This was auto-generated to implement the App Indexing API. 
    * See https://g.co/AppIndexing/AndroidStudio for more information. 
    */ 
    public Action getIndexApiAction() { 
     Thing object = new Thing.Builder() 
       .setName("Login Page") // TODO: Define a title for the content shown. 
       // TODO: Make sure this auto-generated URL is correct. 
       .setUrl(Uri.parse("http://[ENTER-YOUR-URL-HERE]")) 
       .build(); 
     return new Action.Builder(Action.TYPE_VIEW) 
       .setObject(object) 
       .setActionStatus(Action.STATUS_TYPE_COMPLETED) 
       .build(); 
    } 
} 

Answer 1

addToRequestQueue ist ein Verfahren definiert f beheben oder der Volley Application Controller, der in Ihrem Fall AndroidLoginController zu sein scheint. Ändern Sie die Zeile zu

AndroidLoginController.getInstance().addToRequestQueue(strRe‌​q,tag_string_req)

Dies wird vorausgesetzt, Sie erstellt haben, die Singleton mit Standard-Volley-Tutorials oder Android Entwickler-Dokumentation