override fun onCreateOptionsMenu(menu: Menu): Boolean {
// Inflate the menu; this adds items to the action bar if it is present.
var sub= menu.addSubMenu("test")
sub.clearHeader()
sub.add("1")
sub.add("2")
var t = menu.getItem(0)
t.setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS)
t.setIcon(R.drawable.ic_add_black_24dp)
return true
}
这样就可以