Instrumentation test doesn't match view ids from hierarchy

Issue

In short, I'm trying to match view with ID like R.id.signCheckbox using Espresso. When I try to match that view I will get NoMatchingView exception when it's clear that view is present.

After some debugging, I've found out that inside my test class when I eval R.id.signCheckbox I'll get ID: -1000984. Inside cause of the NoMatchingViewException you can actually read whole view hierarchy in some format. There I've found that checkbox has different ID 2131362821. I've read the project R.java and it's also assigning 2131362821 to R.id.signCheckbox.

So when I match withId(2131362821) it's actually working. Why it's not working with R.id.signCheckbox and where that -1000984 id comes from?

Solution

It looks like the good old Invalidate/Restart/Clean/Rebuild fixed the problem.

The IDs are still negative (like -1000984) not matching the R.java IDs, but Espresso will successfully match the views.

Answered By - JoKr