当状态码为 400 时，volley 返回空响应

如何解决当状态码为 400 时，volley 返回空响应

我正在尝试将数据发布到 android 中的 API，它在邮递员中成功地使用了这个 body raw:

{
    "phonenumber": "12345","username": "test","password": "1234","roles": 1
}

成功的响应是：

{
    "message": "Registered successfully!"
}

错误的响应是：

{
    "message": "Failed! this user already registered!"
}

所以在android中，我首先尝试了改造库，如果我尝试注册的用户不存在并且我得到正确的响应，则该帖子可以完美运行 但如果用户存在，则响应返回 null 400 状态代码

所以我尝试使用 volley 来解决问题，但得到了相同的结果 这是我的代码：

private void userSignUp(){

        //defining a progress dialog to show while signing up
        final ProgressDialog progressDialog = new ProgressDialog(this);
        progressDialog.setMessage("Signing Up...");
        progressDialog.show();

        String phonenumber = editTextPhonenumber.getText().toString().trim();
        String username = editTextUsername.getText().toString().trim();
        String password = editTextPassword.getText().toString().trim();

        // url to post our data
        String url = "http://xxxx/api/auth/signup";

        // creating a new variable for our request queue
        RequestQueue queue = Volley.newRequestQueue(SignUpActivity.this);

        JSONObject object = new JSONObject();
        try {
            //input your API parameters
            object.put("phonenumber",phonenumber);
            object.put("username",username);
            object.put("password",password);
            object.put("roles",1);
        } catch (JSONException e) {
            e.printstacktrace();
        }

        JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.POST,url,object,new com.android.volley.Response.Listener<JSONObject>() {
                    @Override
                    public void onResponse(JSONObject response) {
                        Toast.makeText(getApplicationContext(),"String Response : "+ response.toString(),Toast.LENGTH_LONG).show();
                    }
                },new com.android.volley.Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Toast.makeText(getApplicationContext(),"String Response : "+ error.networkResponse.statusCode + "\nResponse Data " + error.networkResponse.data
                        + "\nCause " + error.getCause()
                        + "\nmessage" + error.getMessage(),Toast.LENGTH_LONG).show();
            }

        }){
            @Override
            public String getBodyContentType() {
                return "application/json";
            }
        };

        queue.add(jsonObjectRequest);
}

这是改造版本：

private void userSignUp(){

        //defining a progress dialog to show while signing up
        final ProgressDialog progressDialog = new ProgressDialog(this);
        progressDialog.setMessage("Signing Up...");
        progressDialog.show();

        String phonenumber = editTextPhonenumber.getText().toString().trim();
        String username = editTextUsername.getText().toString().trim();
        String password = editTextPassword.getText().toString().trim();

        //building retrofit object
        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(APIUrl.BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        //Defining retrofit api service
        APIService service = retrofit.create(APIService.class);

        //Defining the user object as we need to pass it with the call
        User user = new User(phonenumber,username,password,1);

        //defining the call
        Call<Result> call = service.createuser(user);

        //calling the api
        call.enqueue(new Callback<Result>() {
            @Override
            public void onResponse(Call<Result> call,Response<Result> response) {
                //hiding progress dialog
                progressDialog.dismiss();
                if(response.isSuccessful()) {
                    Log.d("TAG","onResponse: " + response.body() + "    " + response.errorBody());
                }


                //displaying the message from the response as toast
                Toast.makeText(getApplicationContext(),response.body().getMessage(),Toast.LENGTH_LONG).show();

                //if there is no error
                if (response.body().getMessage() == "User was registered successfully!") {
                    Toast.makeText(getApplicationContext(),"response.body().getMessage()",Toast.LENGTH_LONG).show();
                    //starting profile activity
                    finish();
                    SharedPrefManager.getInstance(getApplicationContext()).userLogin(user);
                    startActivity(new Intent(getApplicationContext(),MainActivity.class));
                }
                else {

                }
            }

            @Override
            public void onFailure(Call<Result> call,Throwable t) {
                progressDialog.dismiss();
                Toast.makeText(getApplicationContext(),t.getMessage(),Toast.LENGTH_LONG).show();
            }
        });

使用它的 apiservice：

public interface APIService {
    //The register call
    @POST("auth/signup")
    Call<Result> createuser(@Body User user);
}

请求 pojo：

public class User {
    @Serializedname("id")
    private int id;

    @Serializedname("phonenumber")
    private String phonenumber;

    @Serializedname("username")
    private String username;

    @Serializedname("password")
    private String password;

    @Serializedname("roles")
    private int roles;

    public User(String phonenumber,String username,String password,int roles) {
        this.phonenumber = phonenumber;
        this.username = username;
        this.password = password;
        this.roles = roles;
    }

    public User(int id,String phonenumber,int roles){
        this.id = id;
        this.phonenumber = phonenumber;
        this.username = username;
        this.roles = roles;
    }

    public User(int id,int roles) {
        this.id = id;
        this.phonenumber = phonenumber;
        this.username = username;
        this.password = password;
        this.roles = roles;
    }

    public int getId() {
        return id;
    }

    public String getPhoneNumber() {
        return phonenumber;
    }

    public String getUsername() {
        return username;
    }

    public String getpassword(){
        return password;
    }

    public int getRoles() {
        return roles;
    }
}

响应pojo：

public class Result {
    @Serializedname("message")
    private String message;

    public Result(String message) {
        this.message = message;
    }

    public String getMessage() {
        return message;
    }

}

有人可以帮我吗？如果用户已经注册，为什么会出现此错误？ 如何像成功响应一样显示错误 {"message": "Failed! this user already registered!"} 本身？

解决方法

实际上状态代码“400”不是错误代码，因此，您可以为此创建处理。我不知道它是否适合你，但根据你的帖子，我认为这只是你处理回复的方式。希望能帮到你 :D

例如：

call.enqueue(new Callback<Result>() {
            @Override
            public void onResponse(Call<Result> call,retrofit2.Response<Result> response) {
                mProgressDialog.dismiss();
                if (response.isSuccessful()){
                    try {
                        if(response.body()!=null) {
               Toast.makeText(SignUpActivity.this,"Welcome to our Apps",Toast.LENGTH_LONG).show();
                        } else if (response.errorBody() != null && response.code() == 400){
                           Toast.makeText(SignUpActivity.this,response.body(),Toast.LENGTH_LONG).show();
                        } else {
                            // If you want to add other handler
                        }
                    }catch (Exception e){
                        e.printStackTrace();
                    }
                } else {
                    showCustomDialog2(response.errorBody().toString());
                    Toast.makeText(SignUpActivity.this,response.errorBody().toString(),Toast.LENGTH_LONG).show();
                }
            }

            @Override
            public void onFailure(Call<Result> call,Throwable t) {
                Log.e("ERROR : ",t.getMessage());
                mProgressDialog.dismiss();
            }
        });

但是，如果您有权编辑服务器端，我建议您为状态代码添加一个新字段，以便您的应用程序更容易检查您的用户数据，以便您的响应 JSON 看起来像这样:

{
    "status": "400","message": "Failed to sign up,user already exist !!"
}