There are no problem with your code it's just that you haven't returned a value on your onItemLongClick boolean. Change it into:
lv.setOnItemLongClickListener(new OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> arg0, View arg1,
final int arg2, long arg3) {
// Make sth on longclick
return true;
}
});
This will prevent long click on doing further actions since take note that a longclick is still a click which is why onclicklistener triggers on this event.