Android常用的Adapter

public class MyAdapter extends  BaseAdapter{

    private List<Fish> list = new ArrayList<>();

    private Context context;

    private LayoutInflater inflater;      

    public MyAdapter(Context context, List<Fish> list){
        this.context = context;
        this.list = list;
        inflater = LayoutInflater.from(context);
    }  

    @Override
    public int getCount(){ return list.size(); }

    @Override
    public Object getItem(int position) { 
        return list.get(position); 
    }

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

    @Override
    public View getView(int position, View convertView,               
                       ViewGroup parent){
        ViewHolder viewHolder;
        if (convertView == null){
            viewHolder = new ViewHolder();
            convertView = inflater.inflate(R.layout.list_item, null);
            viewHolder.textView = (TextView)convertView.findViewById(R.id.text_item);
            convertView.setTag(viewHolder);
        }else {
            viewHolder = (ViewHolder)convertView.getTag();
        }
        ActivityAttr activityAttr = list.get(position);
        viewHolder.textView.setText(activityAttr.getName());
        return convertView; 
    }

    class ViewHolder{
        TextView textView;
    }
}