java - getFilter() on a custom ArrayAdapter not working

Question

I am using a Custom ArrayAdapter to store User information for example sammy, robert, lizie are each one User objects and i am using a User type ArrayList to store all the User objects to ArrayList.

And because it is not a string or int (The ArrayList) the default getFilter does not work, and i have done my research but it is really confusing how the getFilter method works so i can modify myself.

I want to implement the searching based on the name property form the User class

I know i have to implement the Filterable interface in my CustomAdapter class, but the getFilter is really unintuitive.

Here is my CustomAdapter

class CustomArrayAdapter extends ArrayAdapter<User>  implements Filterable {


    CustomArrayAdapter(@NonNull Context context, ArrayList<User> users) {
        super(context, 0, users);
    }

    @NonNull
    @Override
    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {

        User innserUser = getItem(position);

        if (convertView == null){

            convertView = LayoutInflater.from(getContext()).inflate(R.layout.row_layout, parent, false);

        }

        TextView username = (TextView) convertView.findViewById(R.id.userNameContact);
        TextView userNumber = (TextView) convertView.findViewById(R.id.userNumberContact);
        ImageView userImage = (ImageView) convertView.findViewById(R.id.userImageContact);

        try {
            if(innserUser != null) {
                username.setText(innserUser.name);
                userNumber.setText(innserUser.number);
                userImage.setImageBitmap(innserUser.imageBitmap);
            }
        }catch (Exception e){
            e.printStackTrace();
        }

        return convertView;

    }


}

and here is the user class nothing special here

import android.graphics.Bitmap;

public class User {

    String id, name, number;
    Bitmap imageBitmap;

    User(String id, String name, String number, Bitmap imageBitmap){

        this.id = id;
        this.name = name;
        this.number = number;
        this.imageBitmap = imageBitmap;

    }
}

I tied alot of variations of the getFilter from many threads but none of them work for me ,and the one's with good explanations are for BaseAdapter not for ArrayAdapter

I have tried this question and i have tried this question but does not work for me.

I am new to android development field, and this seems particularly unintuitive. Any suggestions would be really appreciated, thank you.

EDIT 1: After the answer of jitesh mohite, Thanks for the replay jitesh mohite

class CustomArrayAdapter extends ArrayAdapter<User>  implements Filterable {


    ArrayList<User> users;

    CustomArrayAdapter(@NonNull Context context, ArrayList<User> users) {
        super(context, 0, users);
        this.users = users;
    }

    @NonNull
    @Override
    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {

        User innserUser = getItem(position);

        if (convertView == null){

            convertView = LayoutInflater.from(getContext()).inflate(R.layout.row_layout, parent, false);

        }

        TextView username = (TextView) convertView.findViewById(R.id.userNameContact);
        TextView userNumber = (TextView) convertView.findViewById(R.id.userNumberContact);
        ImageView userImage = (ImageView) convertView.findViewById(R.id.userImageContact);

        try {
            if(innserUser != null) {
                username.setText(innserUser.name);
                userNumber.setText(innserUser.number);
                userImage.setImageBitmap(innserUser.imageBitmap);
            }
        }catch (Exception e){
            e.printStackTrace();
        }

        return convertView;

    }


    Filter myFilter = new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            FilterResults filterResults = new FilterResults();
            ArrayList<User> tempList=new ArrayList<User>();
            // Add the filter code here
            if(constraint != null && users != null) {
                int length= users.size();
                int i=0;
                while(i<length){
                    User item= users.get(i);
                    //do whatever you wanna do here
                    //adding result set output array

                    //item.name is user.name cause i want to search on name
                    if(item.name.toLowerCase().contains(constraint.toString().toLowerCase()) ) { // Add check here, and fill the tempList which shows as a result

                        tempList.add(item);
                    }

                    i++;
                }
                //following two lines is very important
                //as publish result can only take FilterResults users
                filterResults.values = tempList;
                filterResults.count = tempList.size();
            }
            return filterResults;
        }

        @SuppressWarnings("unchecked")
        @Override
        protected void publishResults(CharSequence contraint, FilterResults results) {
            users = (ArrayList<User>) results.values;
            if (results.count > 0) {
                notifyDataSetChanged();
            } else {
                notifyDataSetInvalidated();
            }
        }
    };

    @Override
    public Filter getFilter() {
        return myFilter;
    }


}

the search is not working on the customadapter still i think i am doing something wrong.

here i am typing something in the search bar but no filtering happens

and if you want to see the searchbar code its nothing special just the usual

@Override
public boolean onCreateOptionsMenu(Menu menu) {

    MenuInflater inflater = getMenuInflater();

    inflater.inflate(R.menu.search_box, menu);

    MenuItem item = menu.findItem(R.id.app_bar_search);

    SearchView searchView = (SearchView)item.getActionView();

    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            return false;
        }

        @Override
        public boolean onQueryTextChange(String newText) {

            customArrayAdapter.getFilter().filter(newText);

            return false;
        }
    });


    return true;



}

Answer 1

Filter myFilter = new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
         FilterResults filterResults = new FilterResults();   
         ArrayList<User> tempList=new ArrayList<User>();
         // Add the filter code here
         if(constraint != null && users!=null) {
             int length= users.size();
             int i=0;
                while(i<length){
                    User item= users.get(i);
                    //do whatever you wanna do here
                    //adding result set output array    
                    if()  {  // Add check here, and fill the tempList which shows as a result

                    tempList.add(item);
                  }

                    i++;
                }
                //following two lines is very important
                //as publish result can only take FilterResults users
                filterResults.values = tempList;
                filterResults.count = tempList.size();
          }
          return filterResults;
      }

      @SuppressWarnings("unchecked")
      @Override
      protected void publishResults(CharSequence contraint, FilterResults results) {
          users = (ArrayList<User>) results.values;
          if (results.count > 0) {
           notifyDataSetChanged();
          } else {
              notifyDataSetInvalidated();
          }  
      }
     };

Lastly, Override this method and return filter instance.

@Override
     public Filter getFilter() {
        return myFilter;
    }

For more reference see https://gist.github.com/tobiasschuerg/3554252