Android NFC radio control using instrumentation
I have always worked a lot with NFC on Android. For this reason, I tend to favor real devices over emulators, since missing an NFC radio means there's no way to truly test the intricacies of radio communication. Unfortunately, one can not power cycle the NFC radio using any official API unless going through hoops and using rooted devices, so ensuring NFC radio power state during testing is an uphill battle. For instrumented test scenarios however, there is actually a way forward. UIAutomator to the rescue While not as elegant as using an API, we can launch the settings screen for NFC and manipulate it through the use of instrumentation. This is NOT possible using modern Espresso which limits you to the app under test, but thankfully the UIAutomator framework is still available. The accompanying UIAutomator Viewer tool (which has now moved to sdk/tools/bin/uiautomatorviewer) is a great asset in this regard as it helps us identify the widget we need to manipulate. What the...