How do I open the SearchView programmatically?

Expand the SearchView with

searchView.setIconified(false);

and collapse it with

searchView.setIconified(true);

You need to change the value of android:showAsAction from ifRoom|collapseActionView to always. The SearchView's attribute android:iconifiedByDefault should be true, which is the default value, otherwise the user can not collapse the SearchView after it was expanded programmatically.

Try to call expandActionView() on MenuItem, not onActionViewExpanded() on ActionView.

It works for me.

MenuItem searchMenuItem = menu.findItem(R.id.menu_search);
searchView = (SearchView) searchMenuItem.getActionView();
searchMenuItem.expandActionView();

If you want to use support library only when necessary, do this

    MenuItem searchMenuItem = menu.findItem(R.id.action_search);
    if (Utils.hasIceCreamSandwich())
        searchMenuItem.expandActionView();
    else MenuItemCompat.expandActionView(searchMenuItem);

else simply do this

    MenuItem searchMenuItem = menu.findItem(R.id.action_search);
    MenuItemCompat.expandActionView(searchMenuItem);