Accessing context.getFilesDir() from InstrumentationTestCase

05 March 2016 on Android.

In order to fix getting null value problem while using Context.getFilesDir() inside InstrumentationTestCase,you need to create files directorory.

adb shell
cd /data/data/package_id_of_app
mkdir files

Now following test assertion codes will not fail.

assertNotNull(getInstrumentation().getContext().getFilesDir());
assertNotNull(getInstrumentation().getContext().openFileInput("aa.db"));