Android :: Android - Start New Intent But No Parent Class

I've a ListActivity with a ListView, onItemClick I start an Intent. Oncreate of this Intent I make a getParent but it's null. if I do this.isChild() it's false.
mPostList.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
Intent IntentDiscution = new Intent(parent.getContext(), EcrireMessage.class);
....
IntentDiscution.putExtras(objetbunble);
parentClass.startActivity(IntentDiscution);
}