Android登录抛出JSON Error: No Value for Error

Question

我一直在做这个简单的Android登录和注册项目。这涉及到通过JSON传递应用密钥令牌，以便调用登录服务。每当我尝试登录时，它都会抛出错误-> JSON错误:没有错误值。解决不了!有人能帮我一下吗?日志显示:"Error 502 - Invalid App Key"

package cscs.sktk; 

import android.app.ProgressDialog;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.android.volley.Request.Method;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.HashMap;
import java.util.Map;
import webservices.utilities.AppConfig;
import webservices.utilities.AppController;
import webservices.utilities.WebServiceParamKeys;
public class LoginActivity extends Activity {
    private static final String TAG = RegisterActivity.class.getSimpleName();
    private Button btnlogin;
    private Button btnLinkToRegister;
    private EditText inputEmail;
    private EditText inputPassword;
    private ProgressDialog pDialog;
    private SessionManager session;

@Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    inputEmail = (EditText) findViewById(R.id.username);
    inputPassword = (EditText) findViewById(R.id.password);
    btnlogin = (Button) findViewById(R.id.lgnbutton);
    btnLinkToRegister = (Button) findViewById (R.id.btnLinkToRegisterScreen);
    // Progress dialog
    pDialog = new ProgressDialog(this);
    pDialog.setCancelable(false);

    // Session manager
    session = new SessionManager(getApplicationContext());
    // Check if user is already logged in or not
    if (session.isLoggedIn())
    {
        // User is already logged in. Take him to main activity
        Intent intent = new Intent(LoginActivity.this, MainActivity.class);
        startActivity(intent);
        finish();
    }
    // Login button Click Event
    btnlogin.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {
            String username = inputEmail.getText().toString().trim();
            String password = inputPassword.getText().toString().trim();
            // Check for empty data in the form
            if (username.isEmpty())
            {
                // Prompt user to enter credentials
                Toast.makeText(getApplicationContext(), "Please enter your Username!!", Toast.LENGTH_LONG).show();
            }
            else if(password.isEmpty())
            {
                Toast.makeText(getApplicationContext(), "Please enter your Password!", Toast.LENGTH_LONG).show();
            }
            else
            {
                checkLogin(username, password);
            }
        }
    });
    // Link to Register Screen
    btnLinkToRegister.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view)
        {
            Intent i = new Intent(getApplicationContext(), RegisterActivity.class);
            startActivity(i);
            finish();
        }
    });
}
/**
 * function to verify login details in mysql db
 * */
private void checkLogin(final String username, final String password) {
    // Tag used to cancel the request
    String tag_string_req = "req_login";
    pDialog.setMessage("Logging you in!");
    showDialog();
    StringRequest strReq = new StringRequest(Method.POST, AppConfig.LOGIN_URL, new Response.Listener<String>() {
        @Override
        public void onResponse(String response) {
            Log.d(TAG, "Login Response: " + response.toString());
            hideDialog();
            try {
                JSONObject jObj = new JSONObject(response);
                boolean error = jObj.getBoolean("error");
                // Check for error node in json
                if (!error) {
                    // user successfully logged in
                    // Create login session
                    session.setLogin(true);

                    // Launch main activity
                    Intent intent = new Intent(LoginActivity.this, MainActivity.class);
                    startActivity(intent);
                    finish();
                }
                else
                {
                    // Error in login. Get the error message
                    String errorMsg = jObj.getString("error_msg");
                    Toast.makeText(getApplicationContext(),
                            errorMsg, Toast.LENGTH_LONG).show();
                }
            } catch (JSONException e)
            {
                // JSON error
                e.printStackTrace();
                Toast.makeText(getApplicationContext(), "Json error: " + e.getMessage(), Toast.LENGTH_LONG).show();
            }
        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Log.e(TAG, "Login Error: " + error.getMessage());
            Toast.makeText(getApplicationContext(),
                    error.getMessage(), Toast.LENGTH_LONG).show();
            hideDialog();
        }
    }) {
        @Override
        protected Map<String, String> getParams()
        {
            // Posting parameters to login url
            Map<String, String> params = new HashMap<String, String>();
            JSONObject paramObj = new JSONObject();
            try
            {
                paramObj.put(WebServiceParamKeys.appKeyToken, "dummyappkey");
                paramObj.put(username, "username");
                paramObj.put(password, "password");
            }
            catch (JSONException e)
            {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return params;
        }
    };
    // Adding request to request queue
    AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
private void showDialog() {
    if (!pDialog.isShowing())
        pDialog.show();
}
private void hideDialog() {
    if (pDialog.isShowing())
        pDialog.dismiss();
}

}

Answer 1

boolean error = jObj.getBoolean("error");

从上面的代码"error"似乎是字符串。所以尝试使用getString()方法获得它，如下所示

字符串错误= jObj.getString("错误");