Android Testing: UIAutomator vs Espresso

Question

I was seeking for test frameworks for Android UI automation and I stumbled upon UI Automator and Espresso and this is the part I am confused about -

1. Both are maintained by Google
2. Both are used for functional UI testing
3. Both are Android only frameworks

So my questions/doubts here are -

• What is the major difference between UI Automator and Espresso?
• Will the source code have to be modified to integrate any of these frameworks?
• Does one framework hold any advantage over the other? If yes, then which framework is the most suitable for UI automation of an Android app?

Answer 1

Actually, you don't need to choose. UIAutomator and Espresso use the same instrumentation runner, so you can use commands from both of them in a single test. Espresso has variety of matchers, assertions and actions on UI, that automator doesn't have:

Espresso Cheat Sheet

Espresso is running in separate thread and it is really fast comparing to other test frameworks.

as Summary: use both of them in your tests, Espresso is main and UIAutomator as an additional tool for OS integration.