在android测试上重新启动应用程序

Question

我正在创建一个库，它将根据用户默认设置处理信息并将其保存在 SharedPreferences 中，开发人员可以在初始化我的库之前在其应用程序上对其进行修改。

每个应用实例只应初始化一次 SDK，否则会触发 RuntimeError。所以在应用程序端的 Application 类应该是这样的：

public class SampleApplication extends Application {
    @Override
    public void onCreate() {
       super.onCreate();

       //Here I can do something that will change the default configs

       //Here I initialize the SDK singleton method
       Sdk.initialize();
    }
}

sdk 抽象实现：

public class Sdk {

    private static SampleApplication sInstance;

    private void Sdk(){
    }

    public static SampleApplication getInstance() throws RuntimeException {
        if (sInstance == null) {
            throw new RuntimeException();
        }
        return sInstance;
    }

    public static void initialize() {
        if (sInstance == null) {
            sInstance = new Sdk();
            //save some information according to what is on the default configurations
        } else {
            throw new RuntimeException("Method was already initialized");
        }
    }
}

当我想测试几个场景来调用这个方法（每个应用程序实例只能调用一次）时，问题就来了。

所以我创建了一个扩展 ApplicationTest 的 Android 测试

应用测试：

  public class ApplicationTest extends ApplicationTestCase<SampleApplication> {
        public ApplicationTest() {
            super(SampleApplication.class);
        }
    }

Android 测试示例：

public class SampleTest extends ApplicationTest {

    @Override
    protected void setUp() throws Exception {
// Here I restart the user preferences although I need to restart the application
//        terminateApplication();
//        createApplication();
        super.setUp();
    }

    @Override
    protected void tearDown() throws Exception {
        super.tearDown();
    }

    public void testDefaultSettings() {
        // Here is where I want to restart application input
        // some values on the user preferences settings in order 
        // to test the output on sharedpreferences by the initialized method  
    }
}

我尝试终止并再次创建应用程序，但没有成功。 我的问题是可以重新启动Android测试的应用程序吗？ 我在这里做错了吗？

Answer 1

我相信，您真正遇到的问题是 InstrumentationTestRunner 的问题：How to prevent ActivityUnitTestCase from calling Application.onCreate?（显然，没有明显的解决方法）

即无论如何，TestRunner 都会在初始化期间调用onCreate()，所以一旦你调用createApplication()，你的Sdk 就已经初始化了。

关于问题本身 - 我相信，唯一的选择是重新考虑 Sdk 类的架构（或添加一些“重置”功能等）

public class TestApplication extends Application {

    @Override
    public void onCreate() {
        super.onCreate();
        // Sdk.terminate(); - If you specify TestApplication as an 
        //                    application class in AndroidManifest, 
        //                    you'll have to uncomment this(due to issue with test runner)
        Sdk.initialize();
    }

    @Override
    public void onTerminate() {
        super.onTerminate();
        Sdk.terminate();
    }
}

Sdk类

public class Sdk {

    private static Sdk sInstance;
    private void Sdk(){
    }

    public static Sdk getInstance() throws RuntimeException {
        if (sInstance == null) {
            throw new RuntimeException();
        }
        return sInstance;
    }

    public static void terminate() {
        sInstance = null;
    }

    public static void initialize() {
        if (sInstance == null) {
            sInstance = new Sdk();
            //save some information according to what is on the default configurations
        } else {
            throw new RuntimeException("Method was already initialized");
        }
    }
}

测试：

public class MyApplicationTest extends ApplicationTestCase<TestApplication> {

    public MyApplicationTest() {
        super(TestApplication.class);
    }

    public void testMultiplicationTests() {
        createApplication();

        int answer = 42;
        assertEquals(42, answer);

        terminateApplication();
    }


    public void testDefaultSettings() {
        createApplication();

        assertNotNull(Sdk.getInstance());

        terminateApplication();
    }
}

注意！如果你为 androidTest 应用特殊的 AndroidManifest，你可以让它不那么痛苦。然后，当 TestRunner 在测试开始之前自行调用 onCreate() 时，您将不会遇到问题。

希望对你有帮助