使用Volley获取验证码

public class MainActivity extends AppCompatActivity {
    private RequestQueue queues ;
    String str;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        queues = Volley.newRequestQueue(this);
        String getcode = getcode();
        System.out.println(getcode+"得到响应");
    }

    public String getcode() {

        new Thread() {
            @Override
            public void run() {
                super.run();
                StringRequest stringRequest = new StringRequest(Request.Method.POST, "http://4444444444444/api/services/app/AppUser/Registe",
                        new Response.Listener<String>() {
                            @Override
                            public void onResponse(String response) {
                                System.out.println("响应" + response);
                                str = response;
                                handler.sendEmptyMessage(1);
                                Log.d("TAG", response);
                            }
                        }, new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Log.e("TAG", error.getMessage(), error);
                        System.out.println("错误" + error);
                    }

                }) {
                    @Override
                    protected Map<String, String> getParams() throws AuthFailureError {
                        // 请求参数
                        Map<String, String> map = new HashMap<String, String>();
                        //new 一个Map  参数放到Map中
                        map.put("Mobile", "15822222222");
                        map.put("UserPwd", "1234567");
                        System.out.println("添加参数");
                        return map;
                    }

                };
                queues.add(stringRequest);
                System.out.println("输出str是:" + str);


            }

        }.start();
        return str;
    }

    Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            System.out.println("得到数据"+str);
        }
    };
    }

implementation 'com.dubsmash.volley:library:2.0.1'