Searchview not showing in Toolbar

Question

I have actually a problem with my Searchview on the Support AppCompat v7 lib 24.0.0.

The SearchView is not shown up no text and input text (look screenshot)

Answer 1

This is very odd. I'm using build tools 25.0.1 and support lib 25.1.0. For me the accepted answer was not necessary, but the way the menu item was defined needs a small change. I need it like so:

Where app:showAsAction is the key. Lint underlines this as red and tells me:

Should use android:showAsAction when using the appcompat library.

However if I have it set to android:showAsAction then the search view simply does not appear. Go figure.