Android 单元测试之Espresso - Google官方UI测试框架

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Android 单元测试之Espresso - Google官方UI测试框架

Espresso是Google官方推出的Instrumentation UI测试框架，在API支持方面有着天然的优势，在推出后很大程度上将替代Robotium。
Espresso官方文档

配置

android {    ...    defaultConfig {        ...        testInstrumentationRunner 'android.support.test.runner.AndroidJUnitRunner'    }    packagingOptions {        exclude 'LICENSE.txt'    }}dependencies {    ...    androidTestCompile 'com.android.support.test:runner:0.5'    androidTestCompile 'com.android.support.test:rules:0.5'    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'    androidTestCompile('com.android.support.test.espresso:espresso-contrib:2.2.2') {        exclude module: 'support-annotations'        exclude module: 'design'        exclude module: 'recyclerview-v7'        exclude module: 'support-v4'    }    androidTestCompile ('com.android.support.test.espresso:espresso-idling-resource:2.2.2') {        exclude module: 'support-annotations'    }    compile 'com.android.support:design:24.1.1'}

构建时，可能会出现annotations 相关报错，加上下面的就好

android {    configurations.all {        resolutionStrategy.force 'com.android.support:support-annotations:23.0.1'    }｝

原因是目前 Espresso 对Android 部分代码只支持到 23.0.1 而我们项目中有些android版本为23.1.1，所以出现了报错

最简单的使用

新建布局

<?xml version="1.0" encoding="utf-8"?>          

新建Activity

public class MainActivity extends AppCompatActivity {    private TextView greetingView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        setTitle(R.string.app_name);        greetingView = (TextView) findViewById(R.id.greeting);    }    public void greet(View v) {        greetingView.setText(R.string.hello);    }}  

新建单元测试

在androidTest中新建

@RunWith(AndroidJUnit4.class)public class MainActivityTest {    @Rule    public ActivityTestRule activityRele = new ActivityTestRule<>(MainActivity.class);    @Test    public void greet() {        onView(withId(R.id.greeting)).check(matches(withText("")));        onView(withId(R.id.greet_button)).check(matches(withText(R.string.greet))).perform(click());        onView(withId(R.id.greeting)).check(matches(withText(R.string.hello)));    }    @Test    public void toolbarTitle() {        CharSequence title = InstrumentationRegistry.getTargetContext().getString(R.string.app_name);        matchToolbarTitle(title);    }    private static ViewInteraction matchToolbarTitle(CharSequence title) {        return onView(isAssignableFrom(Toolbar.class))                .check(matches(withToolbarTitle(is(title))));    }    private static Matcher