ListView Adapter

package com.example;

import java.util.ArrayList;
import java.util.HashMap;

import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;

public class CategoryAdapter extends BaseAdapter
{
    public ArrayList<String> list;
    Context context;
    HashMap<String, String> map;
    Bitmap bitmap;

    public CategoryAdapter(Context context, ArrayList<String> list1) {

        this.context = context;
        this.list = list1;
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return list.size();
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return list.get(position);
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    class ViewHolder {
        Button cate;

    }

    @Override
    public View getView(int position, View convertView, ViewGroup arg2) {

        if (convertView == null) {
            LayoutInflater inflater = (LayoutInflater) context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.language_list_item, null);
            ViewHolder holder = new ViewHolder();

            holder.cate = (Button) convertView.findViewById(R.id.list_btn);

            convertView.setTag(holder);
        }

        final ViewHolder holder1 = (ViewHolder) convertView.getTag();

        holder1.cate.setText(list.get(position));

        holder1.cate.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                Intent intent = new Intent(context, MessagePage.class);
                context.startActivity(intent);

            }
        });

        return convertView;
    }

}