You can try by changing this line to
TextView c = (TextView) view.findViewById(R.id.text);
and remove your first line View curr = parent.getChildAt((int) id);
l2.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,int position, long id)
{
TextView c = (TextView) view.findViewById(R.id.text);
String sel_item = c.getText().toString();
Intent intent = new Intent(SubCatListActivity.this,GridActivity.class);
adapter.imageLoader.clearCache();
intent.putExtra("gall", sel_item);
intent.putExtra("cate", cate);
startActivity(intent);
Toast.makeText(SubCatListActivity.this,sel_item, Toast.LENGTH_SHORT).show();
}});