Get test project context in Android junit test case

Question

Does anyone know how you can get the context of a test project in a test example of Android junit (extends AndroidTestCase).

Note. The test is not a verification test.

Note 2: I need the context of the test project, not the context of the actual application under test.

I need this to load some files from assets from a test project.

Answer 1

A new approach has appeared with the Android Testing Support Library (currently androidx.test:runner:1.1.1 ). Kotlin updated the example:

 class ExampleInstrumentedTest { lateinit var instrumentationContext: Context @Before fun setup() { instrumentationContext = InstrumentationRegistry.getInstrumentation().context } @Test fun someTest() { TODO() } } 

If you want to also launch the application context:

 InstrumentationRegistry.getInstrumentation().targetContext 

Full example: https://github.com/fada21/AndroidTestContextExample

Take a look here: what is the difference between getTargetContext () and getContext (in InstrumentationRegistry)?

Answer 2

After some research, the only working solution seems to be already pointed out in one yorkw. You will need to extend InstrumentationTestCase, and then you can access the context of the test application using getInstrumentation (). GetContext () is a short piece of code that uses the above recommendations:

 public class PrintoutPullParserTest extends InstrumentationTestCase { public void testParsing() throws Exception { PrintoutPullParser parser = new PrintoutPullParser(); parser.parse(getInstrumentation().getContext().getResources().getXml(R.xml.printer_configuration)); } } 

Answer 3

As you can read in the AndroidTestCase source code , the getTestContext() method is hidden.

 /** * @hide */ public Context getTestContext() { return mTestContext; } 

You can get around the @hide annotation with reflection.

Just add the following method to AndroidTestCase :

 /** * @return The {@link Context} of the test project. */ private Context getTestContext() { try { Method getTestContext = ServiceTestCase.class.getMethod("getTestContext"); return (Context) getTestContext.invoke(this); } catch (final Exception exception) { exception.printStackTrace(); return null; } } 

Then call getTestContext() at any time. :)

Answer 4

Update: AndroidTestCase This class is deprecated at API level 24. Use InstrumentationRegistry instead. New tests should be written using the Android Testing Support Library. Link to ad

You must expand from AndroidTestCase instead of TestCase.

AndroidTestCase class overview
Extend this if you need access to resources or other things that depend on the context of activity.

AndroidTestCase - Android Developers

Answer 5

If you want to get context with Kotlin and Mockito, you can do it like this:

 val context = mock(Context::class.java) 

Hope this helps you

Answer 6

This is the right way to get context. Other methods are outdated

 import androidx.test.platform.app.InstrumentationRegistry InstrumentationRegistry.getInstrumentation().context 

Answer 7

If you only need access to the resources of your project, you can use the getActivity () method of the ActivityInstrumentationTestCase2 class :

  //... private YourActivityClass mActivity; @Override protected void setUp() throws Exception { //... mActivity = getActivity(); } //... public void testAccessToResources() { String[] valueList; valueList = mActivity.getResources().getStringArray( com.yourporject.R.array.test_choices); } 

Answer 8

Other answers are out of date. Right now, when you extend AndroidTestCase, there is an mContext Context object that you can use.

Answer 9

You can use Robolectric for unit testing Android on the JVM.

Robolectric is an infrastructure that allows you to write unit tests and run them on the desktop JVM while still using the Android API.

Robolectric provides a JVM-compatible version of the android.jar file. Robolectric handles presentation inflation, resource loading, and much more, which is implemented in native C code on Android devices.

 dependencies { ... // Robolectric testCompile "org.robolectric:robolectric:3.3.2" } 

1. Your tests should be stored in the src/test directory.
2. The class containing your Robolectric test should be annotated with @RunWith(RobolectricTestRunner.class runner).
3. It should also use @Config () to point to your BuildConfig.class class.

for example

 @RunWith(RobolectricTestRunner.class) @Config(constants = BuildConfig.class) public class WelcomeActivityTest { private WelcomeActivity activity; @Before public void setUp() throws Exception { activity = Robolectric.buildActivity( WelcomeActivity.class ) .create() .resume() .get(); } @Test public void shouldNotBeNull() throws Exception { assertNotNull( activity ); } } 

Find out more here.

Answer 10

 import androidx.test.core.app.ApplicationProvider; private Context context = ApplicationProvider.getApplicationContext();