Bdtjtk

So I have been trying to make a feature in my app where I can login and then fetch data from my database through the Django REST Framework. My logging in works as it only uses POST, but retrieving items does not work.

For some reason my AsyncTask does not get called for retrieving posts.

I have placed my AsyncTask for both activities, which are login and posts, on a separate java file only for handling Web Server stuff.

I am wondering if this is because I should put AsyncTask on each activities.

login.java

public class Login extends AppCompatActivity {



    Button LoginButton;

    EditText uUserName, uPassWord;

    WSAdapter.SendAPIRequests AuthHelper;



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_login);



        //SetupHomeBtn = (ImageButton) findViewById(R.id.SetupHomeBtn);



        LoginButton = (Button) findViewById(R.id.LoginButton);



        uUserName = (EditText) findViewById(R.id.LoginUserBox);

        uPassWord = (EditText) findViewById(R.id.LoginPassBox);



        //AuthHelper = new WSAdapter().new SendDeviceDetails();



        // Moves user to the main page after validation

        LoginButton.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                // gets the username and password from the EditText

                String strUserName = uUserName.getText().toString();

                String strPassWord = uPassWord.getText().toString();



                // API url duh

                String APIUrl = "http://192.168.0.18:8000/token-auth/";



                // If the user is authenticated, then transfer to the MainActivity page

                if (APIAuthentication(strUserName, strPassWord, APIUrl)){

                    startActivity(new Intent(Login.this, Posts.class));

                }

            }

        });



    }



    private boolean APIAuthentication(String un, String pw, String url){

        // when it wasn't static -> AuthHelper = new WSAdapter().new SendAPIRequests();

        AuthHelper = new WSAdapter.SendAPIRequests();



        JSONObject postData = new JSONObject();

        try {

            // Attempt to input info to the Django API

            postData.put("username", un);

            postData.put("password", pw);



            // Putting the data to be posted in the Django API

            AuthHelper.execute(url, postData.toString());



            return true;

        } catch (JSONException e) {

            e.printStackTrace();

        }



        return false;

    }

}

posts.java

public class Posts extends AppCompatActivity {



    TextView postsSect;

    Button postsDoneBtn;

    WSAdapter.SendAPIRequests PostsHelper;

    StringBuilder postsBuffer = new StringBuilder();



    @Override

    protected void onResume(){

        super.onResume();

        PostsDetails postDetailsHelper = new PostsDetails();

        postDetailsHelper.ListPosts();

    }



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_posts);



        PostsDetails postDetailsHelper = new PostsDetails();



        postsDoneBtn = (Button) findViewById(R.id.PostsDoneButton);



        postDetailsHelper.callPostDetails("192.168.0.18:8000/api");

        postDetailsHelper.ListPosts();

        postDetailsHelper.postDetailsCalled('n');



        postsDoneBtn.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                startActivity(new Intent(Posts.this, MainActivity.class));



            }

        });

    }



    public class PostsDetails {

        //String post_title, post_content;

        ArrayList<Integer> post_id = new ArrayList<Integer>();

        ArrayList<String> post_title = new ArrayList<String>();

        ArrayList<String> post_content = new ArrayList<String>();



        boolean isPDCalled;



        // sets if Post details are called

        boolean postDetailsCalled(char called) {

            if (called == 'y'){

                return true;

            }

            return false;

        }



        // checks if postsDetails functions are called for AsyncTask

        boolean getIsPDCalled(){

            return isPDCalled;

        }



        // calls the execute for AsyncTask

        private void callPostDetails(String theurl){

            PostsHelper = new WSAdapter.SendAPIRequests();

            // sets if post details are called

            postDetailsCalled('y');

            // executes AsyncTask

            PostsHelper.execute(theurl);

        }



        // sets values for the posts arrays

        public void setPost(int p_id, String p_title, String p_content) {

            post_id.add(p_id);

            post_title.add(p_title);

            post_content.add(p_content);

        }



        // Lists the posts from the database

        public void ListPosts() {

            /////////// add functionality if a post was deleted and was clicked

            postsSect = (TextView) findViewById(R.id.PostsSection);

            postsSect.setText(post_title.get(post_title.size()) + "n");

            for (int i = post_id.size() - 1; i > 0; i--)

            {

                postsSect.append(post_title.get(i));

            }

        }

    }

}

WSAdapter.java

// I forgot what WS stands for, but this class serves as an adapter for JSON and Online stuff

// I think it stands for With-Server Adapter

public class WSAdapter extends AppCompatActivity {



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);



    }



    static public class SendAPIRequests extends AsyncTask<String, String, String> {



        // Add a pre-execute thing



        @Override

        protected String doInBackground(String... params) {



            Log.e("TAG", params[0]);

            Log.e("TAG", params[1]);

            String data = "";



            HttpURLConnection httpURLConnection = null;

            try {



                // Sets up connection to the URL (params[0] from .execute in "login")

                httpURLConnection = (HttpURLConnection) new URL(params[0]).openConnection();



                // Sets the request method for the URL

                httpURLConnection.setRequestMethod("POST");



                // Tells the URL that I am sending a POST request body

                httpURLConnection.setDoOutput(true);



                // To write primitive Java data types to an output stream in a portable way

                DataOutputStream wr = new DataOutputStream(httpURLConnection.getOutputStream());

                // Writes out a byte to the underlying output stream of the data posted from .execute function

                wr.writeBytes("postData=" + params[1]);

                // Flushes the postData to the output stream

                wr.flush();

                wr.close();



                // Representing the input stream

                InputStream in = httpURLConnection.getInputStream();



                // Preparing input stream bytes to be decoded to charset

                InputStreamReader inputStreamReader = new InputStreamReader(in);

                StringBuilder dataBuffer = new StringBuilder();



                // Translates input stream bytes to charset

                int inputStreamData = inputStreamReader.read();

                while (inputStreamData != -1) {

                    char current = (char) inputStreamData;

                    inputStreamData = inputStreamReader.read();

                    // concatenates data characters from input stream

                    dataBuffer.append(current);

                }

                data = dataBuffer.toString();

            } catch (Exception e) {

                e.printStackTrace();

            } finally {

                // Disconnects socket after using

                if (httpURLConnection != null) {

                    httpURLConnection.disconnect();

                }

            }



            Log.e("TAG", data);

            return data;

        }



        @Override

        protected void onPostExecute(String result) {

            super.onPostExecute(result);

            // expecting a response code fro my server upon receiving the POST data

            Log.e("TAG", result);



            Posts.PostsDetails postsHelper = new Posts().new PostsDetails();



            // For posts

            try {

                if (postsHelper.getIsPDCalled()){

                    JSONObject pJObj = new JSONObject(result);

                    JSONArray pJObjArray = pJObj.getJSONArray("posts");



                    for (int i = 0; i < pJObjArray.length(); i++) {

                        JSONObject pJObj_data = pJObjArray.getJSONObject(i);

                        postsHelper.setPost(pJObj_data.getInt("id"), "post_title", "post_content");

                    }

                }



            } catch (JSONException e) {

                //Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();

                Log.d("Json","Exception = "+e.toString());

            }

        }

    }

}

Yes, you can and should put the network calls functions in a separate java file for better readability and test-coverage.

Apart from that, i would suggest to use Retrofit as your HTTP client. It helps you to manage all the dirty things like headers and converters etc, so you can put all your effort on your logic and implementing your callback actions.