RunTimeException in Android espresso when selecting spinner in dialog

Question

I have an activity where some dialog is openend. On this dialog there is a spinner. I want to select a specific value in this spinner, but I get following exception:

Answer 1

I had the same error when I tried to match a text inside an alert dialog. This helped:

onView(withText(text)).inRoot(RootMatchers.isDialog()).perform(click());