Android-从ListView删除项目时遇到问题？

public class IconAdapter extends BaseAdapter
{
private Activity activity;
private Object[] data;
private ArrayList<HashMap<String,String>> listItems;
public static LayoutInflater inflater = null;
private PackageManager pm;
public ArrayList<Boolean> itemChecked = new ArrayList<Boolean>();
private ArrayList<String> itemSelected = new ArrayList<String>();
private ArrayList<TextView> ctv = new ArrayList<TextView>();
private int posi;
private String pkg;

public IconAdapter(Activity a, ArrayList<HashMap<String,String>> items)
{
    activity = a;
    listItems = items;
    data = items.toArray();
    inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    pm = a.getPackageManager();
    for(int i = 0; i < items.size(); i++)
    {
        itemChecked.add(i,false);
    }
    for(int i = 0; i < items.size(); i++)
    {
        itemSelected.add(i,\" \");
    }

}

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

public Object getItem(int position) {
    return position;
}

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

public static class ViewHolder{
    public TextView textView;
    public ImageView imageView;
    public CheckBox checkBox;
}

public View getView(final int position, View convertView, ViewGroup parent)
{
    View row = convertView;
    ViewHolder holder;

    if(row==null)
    {
        row = inflater.inflate(R.layout.item, parent, false);
        holder = new ViewHolder();
        holder.textView = (TextView)row.findViewById(R.id.text1);
        holder.imageView = (ImageView)row.findViewById(R.id.image);
        holder.checkBox = (CheckBox)row.findViewById(R.id.check);
        row.setTag(holder);
    }
    else
    {
        holder = (ViewHolder) row.getTag();
    }


    String s = data[position].toString();
    String[] tokens = s.split(\",\");
    String[] mToken = tokens[0].split(\"=\");
    String taskName = mToken[1];
    String[] mTokens = tokens[1].split(\"=\");
    final String pkgName =  mTokens[1].substring(0, (mTokens[1].length() - 1));


    holder.textView.setText(taskName);
    holder.textView.setTag(pkgName);


    holder.checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        public void onCheckedChanged(CompoundButton button, boolean b) {

                    if (b)
                    {
                        itemChecked.set(position, true);
                        itemSelected.set(position, pkgName);

                    }
                    else
                    {
                        itemChecked.set(position, false);


                    }


        }
    });

    holder.checkBox.setChecked(itemChecked.get(position));


    try{
        Drawable icon =   pm.getApplicationIcon(pkgName);
        holder.imageView.setImageDrawable(icon);
    }
    catch (PackageManager.NameNotFoundException ne)
    {

    }

     return row;
}




public String getPkgName(int position)
{
    return itemSelected.get(position);
}
public void setItemChecked(boolean isChecked)
{

}
}

public void onClick(View view)
{
    int size = icon.getCount();
    for(int i = size-1; i >= 0; i--)
    {
        if(icon.itemChecked.get(i))
        {
            list.remove(i);
        }
    }
    icon.notifyDataSetChanged();
}