I like that it’s the time of the year when I actually have some time to invest in blogging here. Updates have been pretty sporadic this year (another item to add to my list of resolutions once 2013 hits in a few days).
In this post, I’d like to talk a little about Robotium, and how you can use it to automate the QA of your Android applications. Mobile applications are perfect for Quality Assurance automation – they are usually small, have limited functionality when compared with desktop applications, and are rarely complex in terms of testing steps. Also, if your a solo mobile developer, you may not have the time (or money) to invest in proper quality assurance of your applications.
We’ve been using a Robotium based solution written in Java at my day job for a while, to validate the quality of our localized product builds, both as a unit testing tool and as an actual test automation tool used by our QA team.
One of the main reasons why we chose to invest time in Robotium is the fact that it offers flexibility in terms of how it recognizes objects within your app (e.g. like it would have to in order to click a button). This is especially important for us, as we want to develop a solution once, and have it support multiple language versions of our application. We also looked at MonkeyRunner, which ships with the Android SDK. MonkeyRunner uses Jython (a Python implementation in Java) scripts to walk through applications.
I prefer Robotium as MonkeyRunner lacks the tight UI integration offered by Robotium, (although MonkeyRunner is much easier to setup and run).
When developing automated test scripts using Robotium, we can use the text from a UI object to identify that object at run-time, for example the label on a button. What we do is compile the localized resources from all our languages with our test application, so if we switch our device language to German for example, the resources from the ‘values-de’ folder are loaded by our test application, and thus we can add new languages to our automation solution simply by re-packaging the APK file containing our test automation scripts, and it will run on any of our supported locales without code modifications.
One of the disadvantages of this approach, (and almost all UI based test automation solutions to be fair), is that the maintenance may be high – for example, you will probably lose 90% of your code in a UI refresh.
Creating a Simple Robotium Automated Test Case
- First off, download the latest version of Robotium, (3.6 at the time of writing).
- Now simply create a new Android application in the IDE of your choice, I prefer NetBeans due to familiarity, but I know most people like Eclipse for Android development.
- Add the Robotium JAR as a reference in your project.
For the purpose of this example, let’s say we want to click the ‘Cancel’ button in the below screen capture. As I mentioned above, our Robotium code uses the string ID’s to find objects (based on the current device language, we will look for the value of that string ID for that language if available, and use that to look for the object on the current screen).
Code (Finally!)
package com.jc.robotium import android.app.Activity; import android.test.ActivityInstrumentationTestCase2; import com.jayway.android.robotium.solo.Solo; import android.content.res.Resources; import android.content.Context; import java.util.Locale; public class RobotiumExample extends ActivityInstrumentationTestCase2 // Provides functional testing of an activity { private static final String TARGET_PACKAGE_ID = "com.yourcompany.yourapp"; private static final String LAUNCHER_ACTIVITY_FULL_CLASSNAME = "com.yourcompany.yourapp.Activities.MainActivity"; private static Class> launcherActivityClass; private Solo solo; private Activity activity; private Resources res; private Context context; // This will launch the application specified above on the device static { try { launcherActivityClass = Class.forName(LAUNCHER_ACTIVITY_FULL_CLASSNAME); } catch(ClassNotFoundException e) { throw new RuntimeException(e); } } public RobotiumExample() throws ClassNotFoundException { super(TARGET_PACKAGE_ID, launcherActivityClass); } @Override protected void setUp() throws Exception { activity = getActivity(); solo = new Solo(getInstrumentation(), activity); context = getInstrumentation().getContext(); res = context.getResources(); } public void testUI() throws Throwable { // .... // Robotium code begins here // Wait for the 'Cancel' button solo.waitForText(res.getString(R.string.cancel)); // We may want to take a screen capture... solo.takeScreenshot(); // Click the cancel button solo.clickOnText(res.getString(R.string.cancel)); // .... } @Override protected void tearDown() throws Exception { try { solo.finalize(); } catch(Throwable e) { // Catch this } getActivity().finish(); super.tearDown(); }
Notice a few things above:
- We are extending the ActivityInstrumentationTestCase2 class, which provides us with the ability to run test methods on the UI thread.
- The method that contains your test logic must be prefixed with ‘test’, notice mine is called testUI().
- We could have looked for the ‘Cancel’ button by passing the text ‘Cancel’ to the waitForText() and clickOnText() methods, but that would only work on the English version of our product. Instead we use the string ID, and look up the value of that string ID based on the current device locale.
- If you use the ‘takeScreenshot()’ method I have shown an example of above, screen captures will be saved in ‘/sdcard/Robotium-Screenshots/’ on your test device.
Running the Test
Compile the APK containing your test automation script and install it on your test device, along with the APK under test. One ‘gotcha’ here with Robotium is that the APK under test and the APK containing the test logic must be signed with the same certificate. This may not be the case if your APK under test comes out of a build system of some sort. You can use resign.jar to re-sign your APK under test with the same signature as your APK containing the test logic (by running it on the same machine on which you compiled the test APK).
Once both are installed on a test device, we can launch the test from a command prompt via adb:
adb shell am instrument -e class com.jc.robotium.RobotiumExample -w com.jc.robotium/android.test.InstrumentationTestRunner
Conclusion
Robotium is a good test framework for getting automation for Android applications up and running very quickly. It has an active community and updates are released regularly, the latest version (3.6 at time of writing), also seems to be a lot more stable than previous versions.
On the flip side, since we are relying on text resources (which may change frequently), the maintenance on Robotium based automation solutions can be high if your UI changes a lot, which is probably a high possibility for a mobile application.
If your looking for an automation framework for your Android application that you can get up and running quickly, and use to run scripts across an Android application supported in many languages, I would recommend Robotium, and will be keeping a close eye on it as it develops further.