How to create a search filter for custom layout adapter android studio

Question

I am able to make a search filter for a listview with single input but am not able to do it for my custom layout which has 3 values. When using the filter I have created all the text disappears from my list view. I would like to be able to filter any of the input be it FirstName, LastName or FavouriteFood.

(ViewListContents.this).adapter.getFilter().filter(charSequence);

Using this code didn't work.

ViewListContents class:

DatabaseHelper myDB;
ArrayList<User> userList;
ListView listView;
User user;
ThreeColumn_ListAdapter adapter;

private List<User> userL = null;
private ArrayList<User> arraylist;

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.viewcontents_layout);

    myDB = new DatabaseHelper(this);
    final EditText filter = (EditText) findViewById(R.id.searchFilter);

    userList = new ArrayList<>();
    Cursor data = myDB.getListContents();
    int numRows = data.getCount();
    if(numRows == 0){
        Toast.makeText(ViewListContents.this,"The Database is empty  :(.",Toast.LENGTH_LONG).show();
    }else{
        int i=0;
        while(data.moveToNext()){
            user = new User(data.getString(1),data.getString(2),data.getString(3));
            userList.add(i,user);
            System.out.println(data.getString(1)+" "+data.getString(2)+" "+data.getString(3));
            System.out.println(userList.get(i).getFirstName());
            i++;
        }
        adapter =  new ThreeColumn_ListAdapter(this,R.layout.list_adapter_view, userList);
        listView = (ListView) findViewById(R.id.listView);
        listView.setAdapter(adapter);
        //listView.setTextFilterEnabled(true);
    }
    filter.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
            (ViewListContents.this).adapter.getFilter().filter(charSequence);
        }

        @Override
        public void afterTextChanged(Editable editable) {

        }
    });


}

User class:

private String FirstName;
private String LastName;
private String FavFood;

public User(String fName,String lName, String fFood){
    FirstName = fName;
    LastName = lName;
    FavFood = fFood;
}

public String getFirstName() {
    return FirstName;
}

public void setFirstName(String firstName) {
    FirstName = firstName;
}

public String getLastName() {
    return LastName;
}

public void setLastName(String lastName) {
    LastName = lastName;
}

public String getFavFood() {
    return FavFood;
}

public void setFavFood(String favFood) {
    FavFood = favFood;
}

Custom Adapter Class:

private LayoutInflater mInflater;
private ArrayList<User> users;
private int mViewResourceId;

public ThreeColumn_ListAdapter(Context context, int textViewResourceId, ArrayList<User> users) {
    super(context, textViewResourceId, users);
    this.users = users;
    mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    mViewResourceId = textViewResourceId;
}

public View getView(int position, View convertView, ViewGroup parent) {
    convertView = mInflater.inflate(mViewResourceId, null);

    User user = users.get(position);

    if (user != null) {
        TextView firstName = (TextView) convertView.findViewById(R.id.textFirstName);
        TextView lastName = (TextView) convertView.findViewById(R.id.textLastName);
        TextView favFood = (TextView) convertView.findViewById(R.id.textFavFood);
        if (firstName != null) {
            firstName.setText(user.getFirstName());
        }
        if (lastName != null) {
            lastName.setText((user.getLastName()));
        }
        if (favFood != null) {
            favFood.setText((user.getFavFood()));
        }
    }

    return convertView;
}

Answer 1

You have a method with the name of filter (from your adapter class that extends from BaseAdapter). In this method (that returns void) when checking of every data item , instead of check for hole of "input text" do check for every part of "input text" by a simple loop. In this order you could implement a "logical or" checking for existence of each part. When a part includes in the data item , you could stop searching(Ok, this item in true for displaying) and ... .