ArrayList 中需要不同的元素<modelclass></modelclass>

Question

I am developing an app in android studio that takes movie names and places them onto cards that swipe left and right. I am having a problem with my MovieList, it will populate but the same movie name goes into it 20 times rather than what I want which is 20 different movie names from the TMDB API. I just created this new MyAdapter class also. So I am not sure why I am not getting different elements into the list. When I use string instead of my MovieModelClass it gets different elements. OnPostExecute is where I loop through the title and add it to the array

Heres my MainActivity

public class MainActivity extends AppCompatActivity {
    private MyAdapter adapter;
    private ArrayList<MovieModelClass> movieList = new ArrayList<>();
  
    SwipeFlingAdapterView flingContainer;

    private static String JSON_URL = "https://api.themoviedb.org/3/movie/popular?api_key=8099f5720bad1f61f020fdbc855f73db";
    //List<MovieModelClass> movieList;
    //@InjectView(R.id.frame) SwipeFlingAdapterView flingContainer;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        flingContainer = (SwipeFlingAdapterView) findViewById(R.id.frame);
        
        GetData getData = new GetData();
        getData.execute();

     
        flingContainer.setFlingListener(new SwipeFlingAdapterView.onFlingListener() {
           
            @Override
            public void removeFirstObjectInAdapter() {
              
              Log.d("LIST", "removed object!");
               movieList.remove(0);
              adapter.notifyDataSetChanged();
            }

            @Override
            public void onLeftCardExit(Object dataObject) {
                
                Toast.makeText(MainActivity.this, "left", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onRightCardExit(Object dataObject) {
                Toast.makeText(MainActivity.this, "right", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onAdapterAboutToEmpty(int itemsInAdapter) {
            
            }

            @Override
            public void onScroll(float scrollProgressPercent) {
              
            }


        });

        // Optionally add an OnItemClickListener
        flingContainer.setOnItemClickListener(new SwipeFlingAdapterView.OnItemClickListener() {
            @Override
            public void onItemClicked(int itemPosition, Object dataObject) {
                Toast.makeText(MainActivity.this, "click", Toast.LENGTH_SHORT).show();
            }
        });


    }

    public class GetData extends AsyncTask<String, String, String> {

        @Override
        protected String doInBackground(String... strings) {

            String current = "";

            try {
                URL url;
                HttpURLConnection urlConnection = null;

                try {

                    url = new URL(JSON_URL);
                    urlConnection = (HttpURLConnection) url.openConnection();

                    InputStream is = urlConnection.getInputStream();
                    InputStreamReader isr = new InputStreamReader(is);

                    int data = isr.read();
                    while (data != -1) {
                        current += (char) data;
                        data = isr.read();
                    }

                    return current;

                } catch (MalformedURLException e) {
                    e.printStackTrace();;
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                    if (urlConnection != null) {
                        //  urlConnection.disconnect();
                    }
                }

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

            return current;
        }

        @Override
        protected void onPostExecute(@org.jetbrains.annotations.NotNull String s){

            try{
                JSONObject jsonObject = new JSONObject(s);
                JSONArray jsonArray = jsonObject.getJSONArray("results");

                movieList = new ArrayList<>();

                MovieModelClass model = new MovieModelClass();

                for(int i = 0; i< jsonArray.length(); i++) {
                    JSONObject jsonObject1 = jsonArray.getJSONObject(i);
                   
                     model.setName(jsonObject1.getString("title"));
                                
                    movieList.add(model);
                }
         

                adapter = new MyAdapter(MainActivity.this, R.layout.item, movieList);
                flingContainer.setAdapter(adapter);
                adapter.notifyDataSetChanged();


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


        }
    }

and this is MyAdapter class which I use for the arrayAdapter

public class MyAdapter extends ArrayAdapter {

    public MyAdapter(Context context, int resource, ArrayList<MovieModelClass> objects) {
        super(context, resource, objects);
    }


    public View getView(int position, View convertView, ViewGroup parent) {


       MovieModelClass movies = (MovieModelClass) getItem(position);

       if(convertView == null)
       {
           convertView = LayoutInflater.from(getContext()).inflate(R.layout.item, parent, false);
       }

       TextView name = (TextView) convertView.findViewById(R.id.name);

       name.setText(movies.getName());

       return convertView ;
    }
}

and my model class

public class MovieModelClass {
    String name;

    public MovieModelClass(String id) {
        this.name = name;  
    }
    public MovieModelClass() {

    }
    public void setName(String name) {
        this.name = name;
    }
    public String getName() {
        return name;
    }
}

Answer 1

Java reference variable will point an Object unless reassigned

The code below

1. creates a single model object MovieModelClass model = new MovieModelClass(); and assigns to reference model
2. inside the for loop, the same object is updated and added to arraylist
3. this results in multiple occurrence of the same object inside List (its only a single object that is referenced multiple times inside the List)

movieList = new ArrayList<>();

MovieModelClass model = new MovieModelClass();

for(int i = 0; i< jsonArray.length(); i++) {
  JSONObject jsonObject1 = jsonArray.getJSONObject(i);
  model.setName(jsonObject1.getString("title"));
  movieList.add(model);
}

Especially, this part of the MovieModelClass model = new MovieModelClass(); should be moved inside the loop

Fix

movieList = new ArrayList<>();
for(int i = 0; i< jsonArray.length(); i++) {
  JSONObject jsonObject1 = jsonArray.getJSONObject(i);
  MovieModelClass model = new MovieModelClass();
  model.setName(jsonObject1.getString("title"));
  movieList.add(model);
}