olakunle olakunle - 26 days ago 6
Android Question

Custom Listview Adapter with filter Android

Please am trying to implement a filter on my listview. But whenever the text change, the list disappears.Please Help
Here are my codes. The adapter class.

package com.talagbe.schymn;

import java.util.ArrayList;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

public class HymnsAdapter extends ArrayAdapter<Hymns> {
ArrayList<Hymns> hymnarray;
Context context;
LayoutInflater inflater;
int Resource;


public HymnsAdapter(Context context, int resource, ArrayList<Hymns> objects) {
super(context, resource, objects);
// TODO Auto-generated constructor stub

hymnarray=objects;
Resource= resource;
this.context=context;
inflater= (LayoutInflater) context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder holder;
if(convertView==null){

convertView= inflater.inflate(Resource,null);
holder= new ViewHolder();
holder.hymntitle= (TextView) convertView.findViewById(R.id.Hymn_title);
// holder.hymntext= (TextView) convertView.findViewById(R.id.Channel_name);


convertView.setTag(holder);

}else{
holder=(ViewHolder)convertView.getTag();
}

holder.hymntitle.setText(hymnarray.get(position).getTitle());
//holder.hymntext.setText(hymnarray.get(position).getText());

return convertView;


}


static class ViewHolder{

public TextView hymntitle;
public TextView hymntext;

}

}


Here is the other class where am trying to implement the filter. I have an edittext,where i implement on textChangeListener

package com.talagbe.schymn;

import java.util.ArrayList;

import database.DatabaseHelper;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.EditText;
import android.widget.ListView;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.widget.AdapterView.OnItemClickListener;

public class Home extends Fragment {

private static final String DB_NAME = "schymn.sqlite";
private static final String TABLE_NAME = "Hymns";
private static final String Hymn_ID = "_id";
private static final String Hymn_Title = "Title";
private static final String Hymn_Text = "Text";
private SQLiteDatabase database;

ListView list;
EditText search;
HymnsAdapter vadapter;
ArrayList<Hymns> HymnsList;
String url;
Context context=null;


public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
return inflater.inflate(R.layout.index, container,false);
}


@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

list = (ListView)getActivity().findViewById(R.id.hymn_list);
search = (EditText) getActivity().findViewById(R.id.search);
HymnsList = new ArrayList<Hymns>();

DatabaseHelper dbOpenHelper = new DatabaseHelper(getActivity(), DB_NAME);
database = dbOpenHelper.openDataBase();

fillHymns();
//setUpList();

}



private void fillHymns() {
Cursor hymnCursor = database.query(TABLE_NAME,
new String[]
{Hymn_ID, Hymn_Title,Hymn_Text},
null, null, null, null
, Hymn_Title);
hymnCursor.moveToFirst();
if(!hymnCursor.isAfterLast()) {
do {
Hymns hy = new Hymns();
hy.setTitle(hymnCursor.getString(1));
hy.setText(hymnCursor.getString(2));
HymnsList.add(hy);

} while (hymnCursor.moveToNext());
}
hymnCursor.close();
vadapter = new HymnsAdapter(getActivity().getApplicationContext(),R.layout.hymns,HymnsList);
list.setAdapter(vadapter);

list.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {

Intent intent = new Intent(getActivity().getApplicationContext(), Hymn_Text.class);
intent.putExtra("Title",HymnsList.get(position).getTitle());
intent.putExtra("Text",HymnsList.get(position).getText());
startActivity(intent);
//Log.i("Text",HymnsList.get(position).getText());

}








});


search.addTextChangedListener( new TextWatcher() {

@Override
public void onTextChanged(CharSequence cs, int start, int before, int count) {
// TODO Auto-generated method stub
if(count>0){


}

}

@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub

}

@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
Home.this.vadapter.getFilter().filter(s);
Log.i("Changed",s.toString());
}
});
}




}


The log,logs whatever input i type in,but doesn't show the listview. Thank you

Answer

You can use the Filterable interface on your Adapter, see a good example below:

original source and See other example here

public class SearchableAdapter extends BaseAdapter implements Filterable {

    private List<String>originalData = null;
    private List<String>filteredData = null;
    private LayoutInflater mInflater;
    private ItemFilter mFilter = new ItemFilter();

    public SearchableAdapter(Context context, List<String> data) {
        this.filteredData = data ;
        this.originalData = data ;
        mInflater = LayoutInflater.from(context);
    }

    public int getCount() {
        return filteredData.size();
    }

    public Object getItem(int position) {
        return filteredData.get(position);
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        // A ViewHolder keeps references to children views to avoid unnecessary calls
        // to findViewById() on each row.
        ViewHolder holder;

        // When convertView is not null, we can reuse it directly, there is no need
        // to reinflate it. We only inflate a new View when the convertView supplied
        // by ListView is null.
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.list_item, null);

            // Creates a ViewHolder and store references to the two children views
            // we want to bind data to.
            holder = new ViewHolder();
            holder.text = (TextView) convertView.findViewById(R.id.list_view);

            // Bind the data efficiently with the holder.

            convertView.setTag(holder);
        } else {
            // Get the ViewHolder back to get fast access to the TextView
            // and the ImageView.
            holder = (ViewHolder) convertView.getTag();
        }

        // If weren't re-ordering this you could rely on what you set last time
        holder.text.setText(filteredData.get(position));

        return convertView;
    }

    static class ViewHolder {
        TextView text;
    }

    public Filter getFilter() {
        return mFilter;
    }

    private class ItemFilter extends Filter {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {

            String filterString = constraint.toString().toLowerCase();

            FilterResults results = new FilterResults();

            final List<String> list = originalData;

            int count = list.size();
            final ArrayList<String> nlist = new ArrayList<String>(count);

            String filterableString ;

            for (int i = 0; i < count; i++) {
                filterableString = list.get(i);
                if (filterableString.toLowerCase().contains(filterString)) {
                    nlist.add(filterableString);
                }
            }

            results.values = nlist;
            results.count = nlist.size();

            return results;
        }

        @SuppressWarnings("unchecked")
        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
            filteredData = (ArrayList<String>) results.values;
            notifyDataSetChanged();
        }

    }
}

//in your Activity or Fragment where of Adapter is instantiated :

editTxt.addTextChangedListener(new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        System.out.println("Text ["+s+"]");

        mSearchableAdapter.getFilter().filter(s.toString());                           
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count,
            int after) {

    }

    @Override
    public void afterTextChanged(Editable s) {
    }
});