Failing to connect to connect and android application to sqlserver using JSON

See more:

Mobile

Android

Hello guys am new to android but am having problem connection my android app to sqlServer using JSON..i load the emulator i get these errors when am invoking the authetication function..

07-20 20:55:48.871: D/AndroidRuntime(2082): Shutting down VM
07-20 20:55:48.872: E/AndroidRuntime(2082): FATAL EXCEPTION: main
07-20 20:55:48.872: E/AndroidRuntime(2082): Process: com.example.tropical, PID: 2082
07-20 20:55:48.872: E/AndroidRuntime(2082): java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.widget.Toast.<init>(Toast.java:101)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.widget.Toast.makeText(Toast.java:250)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at com.example.tropical.Login$AsyncLogin.onPreExecute(Login.java:87)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.os.AsyncTask.execute(AsyncTask.java:535)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at com.example.tropical.Login$1.onClick(Login.java:49)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.view.View.performClick(View.java:4756)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.view.View$PerformClick.run(View.java:19749)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.os.Handler.handleCallback(Handler.java:739)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.os.Handler.dispatchMessage(Handler.java:95)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.os.Looper.loop(Looper.java:135)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at android.app.ActivityThread.main(ActivityThread.java:5221)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at java.lang.reflect.Method.invoke(Native Method)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at java.lang.reflect.Method.invoke(Method.java:372)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
07-20 20:55:48.872: E/AndroidRuntime(2082): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
07-20 20:55:51.497: D/gralloc_goldfish(2101): Emulator without GPU emulation detected.
07-20 20:55:59.339: I/Choreographer(2101): Skipped 54 frames!  The application may be doing too much work on its main thread.

And this is my code..

protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_login);
		etUserName = (EditText) findViewById(R.id.txtUserID);
		etPassword = (EditText) findViewById(R.id.txtpswd);
        btnLogin = (Button) findViewById(R.id.btnlogin);
		//etUserName =(EditText)findViewById(R.id.)
        btnLogin.setOnClickListener(new View.OnClickListener() {
        	 
            @Override
            public void onClick(View v) {
                  // TODO Auto-generated method stub

                  String username=etUserName.getText().toString();
                  String password=etPassword.getText().toString();

                  // Execute the AsyncLogin class
                  //new AsyncLogin().execute(username,password);
                  AsyncLogin xx = new AsyncLogin();
                  xx.execute(username,password);

            }
      });
	}
	
	protected class AsyncLogin extends AsyncTask<string,> {
		 
        String userName=null;
        @Override
        protected Boolean doInBackground(String... params) {

              RestAPI api = new RestAPI();
        
              boolean userAuth = false;
              try {

                    // Call the User Authentication Method in API
                    JSONObject jsonObj = api.UserAuthetication(params[0],
                                params[1]);

                    //Parse the JSON Object to boolean
                    JSONParser parser = new JSONParser();
                    userAuth = parser.parseUserAuth(jsonObj);
                    userName=params[0];
              } catch (Exception e) {
                    // TODO Auto-generated catch block
                    Log.d("AsyncLogin", e.getMessage());

              }
              return userAuth;

}

code in the JSONObject java class

public JSONObject UserAuthetication(String UserName,String Pin) throws Exception {
       JSONObject result = null;
       JSONObject o = new JSONObject();
       JSONObject p = new JSONObject();
       o.put("interface","RestAPI");
       o.put("method", "UserAuthetication");
       p.put("UserName",mapObject(UserName));
       p.put("Pin",mapObject(Pin));
       o.put("parameters", p);
       String s = o.toString();
       String r = load(s);
       result = new JSONObject(r);
       return result;
   }