Android tests are based on JUnit, and you can run them either as local unit tests on the JVM or as instrumented tests on an Android device. This page provides an introduction to the concepts and tools for building Android tests
Local unit tests JUnit
@RunWith(AndroidJUnit4.class)
@LargeTest
public class MainActivityInstrumentationTest {
@Rule
public ActivityTestRule mActivityRule = new ActivityTestRule<>(
MainActivity.class);
@Test
public void sayHello(){
onView(withText("Say hello!")).perform(click());
onView(withId(R.id.textView)).check(matches(withText("Hello, World!")));
}
}
Instrumented tests Example dependencies { androidTestCompile 'com.android.support:support-annotations:24.0.0' androidTestCompile 'com.android.support.test:runner:0.5' androidTestCompile 'com.android.support.test:rules:0.5' // Optional -- Hamcrest library androidTestCompile 'org.hamcrest:hamcrest-library:1.3' // Optional -- UI testing with Espresso androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2' // Optional -- UI testing with UI Automator androidTestCompile 'com.android.support.test.uiautomator:uiautomator-v18:2.1.2' }
android { defaultConfig { testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner" } }
Instrumented Unit Test Class
import android.os.Parcel;
import android.support.test.runner.AndroidJUnit4;
import android.util.Pair;
import org.junit.Test;
import org.junit.runner.RunWith;
import java.util.List;
import static org.hamcrest.Matchers.is;
import static org.junit.Assert.assertThat;
@RunWith(AndroidJUnit4.class)
@SmallTest
public class LogHistoryAndroidUnitTest {
public static final String TEST_STRING = "This is a string";
public static final long TEST_LONG = 12345678L;
private LogHistory mLogHistory;
@Before
public void createLogHistory() {
mLogHistory = new LogHistory();
}
@Test
public void logHistory_ParcelableWriteRead() {
// Set up the Parcelable object to send and receive.
mLogHistory.addEntry(TEST_STRING, TEST_LONG);
// Write the data.
Parcel parcel = Parcel.obtain();
mLogHistory.writeToParcel(parcel, mLogHistory.describeContents());
// After you're done with writing, you need to reset the parcel for reading.
parcel.setDataPosition(0);
// Read the data.
LogHistory createdFromParcel = LogHistory.CREATOR.createFromParcel(parcel);
List<Pair<String, Long>> createdFromParcelData = createdFromParcel.getData();
// Verify that the received data is correct.
assertThat(createdFromParcelData.size(), is(1));
assertThat(createdFromParcelData.get(0).first, is(TEST_STRING));
assertThat(createdFromParcelData.get(0).second, is(TEST_LONG));
}
}