立即更新微调数据

Question

嗨我会询问我的脚本，当我在插入的mysql数据库数据中插入新数据但没有立即添加到微调器时，所以我无法选择刚刚输入的数据。 （我们必须旋转手机才能显示我刚输入的数据）

插入数据后，我称之为：

requestQueue.add(jsonObjectRequest);

，但它失败了:(，旋转器仍然没有刷新数据。 我的代码有什么问题？

非常感谢--- grazie：）

这是我的代码：

package com.app.example.nyoba;

   import....

  public class MainActivity extends AppCompatActivity {

    EditText firstname, lastname, age;
    Button insert, show;
    TextView result;
    RequestQueue requestQueue;
    String insertUrl = "http://10.10.10.1/trial/mysql/insertStudent.php";
    String showUrl = "http://10.10.10.1/trial/mysql/showStudent.php";
    ArrayList<String> ar = new ArrayList<String>();
    JsonObjectRequest jsonObjectRequest;


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

    firstname   = (EditText) findViewById(R.id.editText);
    lastname    = (EditText) findViewById(R.id.editText2);
    age         = (EditText) findViewById(R.id.editText3);
    insert      = (Button) findViewById(R.id.insert);
    show        = (Button) findViewById(R.id.show);
    result      = (TextView) findViewById(R.id.result);


    requestQueue = Volley.newRequestQueue(getApplicationContext());

    show.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.POST, showUrl, new Response.Listener<JSONObject>() {
                @Override
                public void onResponse(JSONObject response) {

                    try {
                        JSONArray students = response.getJSONArray("students");

                        //set TextView blank and scrollable
                        result.setText("");
                        result.setMovementMethod(new ScrollingMovementMethod());

                        for (int i = 0; i < students.length(); i++) {
                            JSONObject student = students.getJSONObject(i);

                            String firstname = student.getString("firstname");
                            String lastname = student.getString("lastname");
                            String age = student.getString("age");

                            result.append(firstname + " " + lastname + " " + age + "\n");
                        }
                        result.append("===\n");

                    } catch (JSONException e) {
                        e.printStackTrace();
                    }

                }
            }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    System.out.println(error.getMessage());
                }
            });
            requestQueue.add(jsonObjectRequest);
        }

    });


    insert.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            StringRequest request = new StringRequest(Request.Method.POST, insertUrl, new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {

                    System.out.println(response.toString());
                    Log.w("RESPONSE", "" + response.toString());
                }
            }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {

                }
            }) {

                @Override
                protected Map<String, String> getParams() throws AuthFailureError {
                    Map<String, String> parameters = new HashMap<String, String>();
                    parameters.put("firstname", firstname.getText().toString());
                    parameters.put("lastname", lastname.getText().toString());
                    parameters.put("age", age.getText().toString());

                    return parameters;
                }
            };

            requestQueue.add(request);
            requestQueue.add(jsonObjectRequest);
        }
    });




    jsonObjectRequest = new JsonObjectRequest(Request.Method.POST, showUrl, new Response.Listener<JSONObject>() {
        @Override
        public void onResponse(JSONObject response) {
            Spinner dropdown = (Spinner)findViewById(R.id.planets_spinner);
            final ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_spinner_dropdown_item, ar);
            dropdown.setAdapter(adapter);

            try {
                JSONArray students = response.getJSONArray("students");

                for (int i = 0; i < students.length(); i++) {
                    JSONObject student = students.getJSONObject(i);

                    String firstname = student.getString("firstname");
                    ar.add(firstname);
                }
                adapter.notifyDataSetChanged();
                Log.w("CHECK", "DI CLASS= " + adapter.getCount());

            } catch (JSONException e) {
                e.printStackTrace();
            }

        }
    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            System.out.println(error.getMessage());
        }
    });
    requestQueue.add(jsonObjectRequest);


    // get selected item
    Spinner dropdown = (Spinner)findViewById(R.id.planets_spinner);
    dropdown.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            Toast.makeText(MainActivity.this, "Selected= " + parent.getSelectedItem().toString(), Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });
   }
 }