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diff --git a/docs/html/training/activity-testing/activity-basic-testing.jd b/docs/html/training/activity-testing/activity-basic-testing.jd new file mode 100644 index 0000000..016289d --- /dev/null +++ b/docs/html/training/activity-testing/activity-basic-testing.jd @@ -0,0 +1,227 @@ +page.title=Creating and Running a Test Case +trainingnavtop=true + +@jd:body + +<!-- This is the training bar --> +<div id="tb-wrapper"> +<div id="tb"> + +<h2>This lesson teaches you to</h2> +<ol> + <li><a href="#testcase">Create a Test Case for Activity Testing</a> + <ol> + <li><a href="#fixture">Set Up Your Test Fixture</a></li> + <li><a href="#preconditions">Add Test Preconditions</a></li> + <li><a href="#test_method">Add Test Methods to Verify Your Activity</a></li> + </ol> + </li> + <li><a href="#build_run">Build and Run Your Test</a></li> +</ol> + +<h2>You should also read</h2> +<ul> +<li><a href="{@docRoot}tools/testing/testing_android.html">Testing +Fundamentals</a></li> +</ul> + +</div> +</div> +<p>In order to verify that there are no regressions in the layout design and +functional behavior in your application, it's important to +create a test for each {@link android.app.Activity} in your application. For +each test, you need to create the individual parts of a test case, including +the test fixture, preconditions test method, and {@link android.app.Activity} +test methods. You can then run your test to get a test report. If any test +method fails, this might indicate a potential defect in your code.</p> +<p class="note"><strong>Note:</strong> In the Test-Driven Development (TDD) +approach, instead of writing most or all of your app code up-front and then +running tests later in the development cycle, you would progressively write +just enough production code to satisfy your test dependencies, update your +test cases to reflect new functional requirements, and iterate repeatedly this +way.</p> + +<h2 id="testcase">Create a Test Case</h2> +<p>{@link android.app.Activity} tests are written in a structured way. +Make sure to put your tests in a separate package, distinct from the code under +test.</p> +<p>By convention, your test package name should follow the same name as the +application package, suffixed with <strong>".tests"</strong>. In the test package +you created, add the Java class for your test case. By convention, your test case +name should also follow the same name as the Java or Android class that you +want to test, but suffixed with <strong>“Test”</strong>.</p> +<p>To create a new test case in Eclipse:</p> +<ol type="a"> + <li>In the Package Explorer, right-click on the {@code /src} directory for +your test project and select <strong>New > Package</strong>.</li> + <li>Set the <strong>Name</strong> field to +{@code <your_app_package_name>.tests} (for example, +{@code com.example.android.testingfun.tests}) and click +<strong>Finish</strong>.</li> + <li>Right-click on the test package you created, and select +<strong>New > Class</strong>.</li> + <li>Set the <strong>Name</strong> field to +{@code <your_app_activity_name>Test} (for example, +{@code MyFirstTestActivityTest}) and click <strong>Finish</strong>.</li> +</ol> + +<h3 id="fixture">Set Up Your Test Fixture</h3> +<p>A <em>test fixture</em> consists of objects that must be initialized for +running one or more tests. To set up the test fixture, you can override the +{@link junit.framework.TestCase#setUp()} and +{@link junit.framework.TestCase#tearDown()} methods in your test. The +test runner automatically runs {@link junit.framework.TestCase#setUp()} before +running any other test methods, and {@link junit.framework.TestCase#tearDown()} +at the end of each test method execution. You can use these methods to keep +the code for test initialization and clean up separate from the tests methods. +</p> +<p>To set up your test fixture in Eclipse:</p> +<ol> +<li>In the Package Explorer, double-click on the test case that you created +earlier to bring up the Eclipse Java editor, then modify your test case class +to extend one of the sub-classes of {@link android.test.ActivityTestCase}. +<p>For example:</p> +<pre> +public class MyFirstTestActivityTest + extends ActivityInstrumentationTestCase2<MyFirstTestActivity> { +</pre> +</li> +<li>Next, add the constructor and {@link junit.framework.TestCase#setUp()} +methods to your test case, and add variable declarations for the +{@link android.app.Activity} that you want to test.</p> +<p>For example:</p> +<pre> +public class MyFirstTestActivityTest + extends ActivityInstrumentationTestCase2<MyFirstTestActivity> { + + private MyFirstTestActivity mFirstTestActivity; + private TextView mFirstTestText; + + public MyFirstTestActivityTest() { + super(MyFirstTestActivity.class); + } + + @Override + protected void setUp() throws Exception { + super.setUp(); + mFirstTestActivity = getActivity(); + mFirstTestText = + (TextView) mFirstTestActivity + .findViewById(R.id.my_first_test_text_view); + } +} +</pre> +<p>The constructor is invoked by the test runner to instantiate the test +class, while the {@link junit.framework.TestCase#setUp()} method is invoked by +the test runner before it runs any tests in the test class.</p> +</li> +</ol> + +<p>Typically, in the {@link junit.framework.TestCase#setUp()} method, you +should:</p> +<ul> +<li>Invoke the superclass constructor for +{@link junit.framework.TestCase#setUp()}, which is required by JUnit.</li> +<li>Initialize your test fixture state by: + <ul> + <li>Defining the instance variables that store the state of the fixture.</li> + <li>Creating and storing a reference to an instance of the +{@link android.app.Activity} under test.</li> + <li>Obtaining a reference to any UI components in the +{@link android.app.Activity} that you want to test.</li> + </ul> +</ul> + +<p>You can use the +{@link android.test.ActivityInstrumentationTestCase2#getActivity()} method to +get a reference to the {@link android.app.Activity} under test.</p> + +<h3 id="preconditions">Add Test Preconditions</h3> +<p>As a sanity check, it is good practice to verify that the test fixture has +been set up correctly, and the objects that you want to test have been correctly +instantiated or initialized. That way, you won’t have to see +tests failing because something was wrong with the setup of your test fixture. +By convention, the method for verifying your test fixture is called +{@code testPreconditions()}.</p> + +<p>For example, you might want to add a {@code testPreconditons()} method like +this to your test case:</p> + +<pre> +public void testPreconditions() { + assertNotNull(“mFirstTestActivity is null”, mFirstTestActivity); + assertNotNull(“mFirstTestText is null”, mFirstTestText); +} +</pre> + +<p>The assertion methods are from the JUnit {@link junit.framework.Assert} +class. Generally, you can use assertions to +verify if a specific condition that you want to test is true. +<ul> +<li>If the condition is false, the assertion method throws an +{@link android.test.AssertionFailedError} exception, which is then typically +reported by the test runner. You can provide a string in the first argument of +your assertion method to give some contextual details if the assertion fails.</li> +<li>If the condition is true, the test passes.</li> +</ul> +<p>In both cases, the test runner proceeds to run the other test methods in the +test case.</p> + +<h3 id="test_method">Add Test Methods to Verify Your Activity</h3> +<p>Next, add one or more test methods to verify the layout and functional +behavior of your {@link android.app.Activity}.</p> +<p>For example, if your {@link android.app.Activity} includes a +{@link android.widget.TextView}, you can add a test method like this to check +that it has the correct label text:</p> +<pre> +public void testMyFirstTestTextView_labelText() { + final String expected = + mFirstTestActivity.getString(R.string.my_first_test); + final String actual = mFirstTestText.getText().toString(); + assertEquals(expected, actual); +} +</pre> + +<p>The {@code testMyFirstTestTextView_labelText()} method simply checks that the +default text of the {@link android.widget.TextView} that is set by the layout +is the same as the expected text defined in the {@code strings.xml} resource.</p> +<p class="note"><strong>Note:</strong> When naming test methods, you can use +an underscore to separate what is being tested from the specific case being +tested. This style makes it easier to see exactly what cases are being tested.</p> +<p>When doing this type of string value comparison, it’s good practice to read +the expected string from your resources, instead of hardcoding the string in +your comparison code. This prevents your test from easily breaking whenever the +string definitions are modified in the resource file.</p> +<p>To perform the comparison, pass both the expected and actual strings as +arguments to the +{@link junit.framework.Assert#assertEquals(java.lang.String, java.lang.String) assertEquals()} +method. If the values are not the same, the assertion will throw an +{@link junit.framework.AssertionFailedError} exception.</p> +<p>If you added a {@code testPreconditions()} method, put your test methods +after the {@code testPreconditions()} definition in your Java class.</p> +<p>For a complete test case example, take a look at +{@code MyFirstTestActivityTest.java} in the sample app.</p> + +<h2 id="build_run">Build and Run Your Test</h2> +<p>You can build and run your test easily from the Package Explorer in +Eclipse.</p> +<p>To build and run your test:</p> +<ol> +<li>Connect an Android device to your machine. On the device or emulator, open +the <strong>Settings</strong> menu, select <strong>Developer options</strong> +and make sure that USB debugging is enabled.</li> +<li>In the Project Explorer, right-click on the test class that you created +earlier and select <strong>Run As > Android Junit Test</strong>.</li> +<li>In the Android Device Chooser dialog, select the device that you just +connected, then click <strong>OK</strong>.</li> +<li>In the JUnit view, verify that the test passes with no errors or failures.</li> +</ol> +<p>For example, if the test case passes with no errors, the result should look +like this:</p> +<img src="{@docRoot}images/training/activity-testing_lesson2_MyFirstTestActivityTest_result.png" alt="" /> +<p class="img-caption"> + <strong>Figure 1.</strong> Result of a test with no errors. +</p> + + + |