将Android连接到服务器

Question

我在Android中有一个简单注册表单的注册脚本。首先，我使用Volley库作为前端部分。

 private void registerUser(final String firstName, final String lastName, final String email, String password) {


    String tag_json_obj = "json_obj_req";

    final ProgressDialog pDialog = new ProgressDialog(this);
    pDialog.setMessage("posting...");
    pDialog.show();



    final HashMap<String, String> postParams = new HashMap<String, String> 
    ();
    postParams.put("firstName", firstName);
    postParams.put("lastName", lastName);
    postParams.put("email", email);
    postParams.put("password", password);


    Response.Listener<JSONObject> listener;
    Response.ErrorListener errorListener;
    final JSONObject jsonObject = new JSONObject(postParams);

    JsonObjectRequest jsonObjReq = new JsonObjectRequest(AppConfig.URL_REGISTER, jsonObject,
            new com.android.volley.Response.Listener<JSONObject>() {

                @Override
                public void onResponse(JSONObject response) {
                    Log.d("TAG", response.toString());
                    try {
                        //Toast.makeText(getApplicationContext(), response.getString("message"), Toast.LENGTH_LONG).show();
                        // Toast.makeText(getApplicationContext(), "Thank you for your post", Toast.LENGTH_LONG).show();

                        if (response.getString("status").equals("fail")) {


                            //session.setLogin(true);
                            pDialog.dismiss();

                            Toast.makeText(getApplicationContext(),response.getString("message"), Toast.LENGTH_SHORT).show();
                            //startActivity(intent);

                            //finish();
                        }else{
                            Toast.makeText(getApplicationContext(), response.getString("message"), Toast.LENGTH_SHORT).show();
                        }
                    } catch (JSONException e) {
                        Log.e("TAG", e.toString());
                    }
                    pDialog.dismiss();
                }
            }, new com.android.volley.Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            //VolleyLog.d("TAG", "Error: " + error.getMessage());
            pDialog.dismiss();

        }
    }) {

        @Override
        public String getBodyContentType() {
            return "application/json; charset=utf-8";
        }


    };


    // Adding request to request queue
    AppController.getInstance().addToRequestQueue(jsonObjReq, tag_json_obj);

}

这部分工作正常，因为我可以得到JSON。

{"status":"fail","message":"Missing POST parameter(s)"}

PHP脚本是。

 <?php
require 'connect.php';
require 'functions.php';

if(logged_in())
{
header("location:profile.php");
exit();
}


 if (isset($_POST['firstName']) && isset($_POST['lastName']) &&    
 isset($_POST['email']) && isset($_POST['password'])) {

$firstName = $_POST['firstName'];
$lastName = $_POST['lastName'];
$email = $_POST['email'];
$password = $_POST['password'];

$stmt = $con->prepare('
    INSERT INTO
        users
        (firstName,lastName,email,password)
    VALUES
        (?,?,?,?)
');

if ( !$stmt ) {
    $result = array('status'=>'fail', 'message'=>'prepare failed');
}
else if ( !$stmt->bind_param('ssss', $firstName, $lastName, $email, $password) ) {
    $result = array('status'=>'fail', 'message'=>'bind failed');
}
else if ( !$stmt->execute() ) {
    $result = array('status'=>'fail', 'message'=>'execute/insert failed');
}
else {
    $result = array('status'=>'success', 'message'=>'Successfully    
    registered');
   }
 }
   else {
      $result = array('status'=>'fail', 'message'=>'Missing POST 
       parameter(s)');
   }

 echo json_encode($result);

  ?>

问题是没有设置$ _POST变量，这就是我得到JSON响应的原因。我知道对于html表单你设置post变量如$ _POST ['输入字段的名称']，但在我的情况下我不想要那样。