NullPointer Exception when using Espresso

Question

I\'m trying to use Espresso. But I got this error and I have no if I\'m missing some codes.

any thoughts will be highly appreciated.

error log:

Answer 1

You should use GoogleInstrumentationTestRunner, as others mentioned. If you build with ant, You need to add an element to the "project" directive in build.xml of the Test Project like below.

in build.xml

    ...