Android单元测试

创建android studio工程，在app目录下的build.gradle中加入JUnit4的依赖。

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:24.0.0-beta1'
}

创建Unit Test

创建测试类Tools

public class Tools {
    public double sum(double a ,double b){
        return 0;
    }

    public double abs(double value){
        return 0;
    }
}

在待测试的类(Tools)代码编辑器内，右键选择Go to -> Test
或者使用快捷键Ctrl + Shift + T，Create New Test 。
Testing library选择JUnit4
Generate选择setUp/@Before
Destionation package选择生成的测试类的包路径
如下图：

1.PNG

创建成功后会在app/src/test/java/me/peace/junit下生成测试类(me/peace/junit即Destionation package)
一般与javas相关的单元测试选择test/java目录，与android相关的选择androidTest/java，若缺少这两个目录请自行创建

2.PNG

在这个测试类中加入具体的测试内容

public class ToolsTest {
    private Tools mTools;

    @Before
    public void setUp() throws Exception {
        mTools = new Tools();
        System.out.println("Before - setUp");
    }

    @Test
    public void testSum() throws Exception {
        assertEquals(48d,mTools.sum(46d,2d),0);
        System.out.println("Test - testSum");
    }

    @Test
    public void testAbs() throws Exception {
        assertEquals(46,mTools.abs(-46),0);
        System.out.println("Test - testAbs");
    }
}

实现Tools类

public class Tools {
    public double sum(double a ,double b){
        return a + b;
    }

    public double abs(double value){
        return Math.abs(value);
    }
}

Run Test Unit

右键ToolsTest类，选择Run->ToolsTest
测试结果：

3.PNG

补充

Generate选择setUp/@Before和tearDown/@After
其运行顺序是setUp->测试的方法->tearDown(即Before->Test->After，且每个Test方法都会去执行一次setUp和tearDown方法)
测试结果：

4.PNG

使用Espresso进行Instrumentaion Test

在build.gradle中配置Espresso,在defaultConfig中添加

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

在dependencies中添加

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'

完整的内容

apply plugin: 'com.android.application'

android {
    compileSdkVersion 24
    buildToolsVersion "24.0.2"

    defaultConfig {
        applicationId "me.peace.espressostudy"
        minSdkVersion 15
        targetSdkVersion 24
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:24.0.0-beta1'
    androidTestCompile 'com.android.support:support-annotations:24.0.0-beta1'
    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'
}

编辑layout的布局文件,效果如图

5.PNG

在MainActivity中加入如下代码

 //按钮点击事件处理
 public void print(View v){
     TextView textView = (TextView)findViewById(R.id.textview);
     EditText editText = (EditText)findViewById(R.id.edittext);
     textView.setText("message => " + editText.getText().toString().trim());
 }

在androidTest/java目录下创建MainActivityTest并且添加如下代码

import static android.support.test.espresso.Espresso.onView;
import static android.support.test.espresso.action.ViewActions.click;
import static android.support.test.espresso.action.ViewActions.closeSoftKeyboard;
import static android.support.test.espresso.action.ViewActions.typeText;
import static android.support.test.espresso.assertion.ViewAssertions.matches;
import static android.support.test.espresso.matcher.ViewMatchers.withId;
import static android.support.test.espresso.matcher.ViewMatchers.withText;

@RunWith(AndroidJUnit4.class)
@LargeTest
public class MainActivityTest{
    private String mExpectedString = "Hello";

    @Rule
    public ActivityTestRule<MainActivity> mActivityRule = new ActivityTestRule(MainActivity.class);

    @Test
    public void print(){
        onView(withId(R.id.edittext)).perform(typeText(mExpectedString),closeSoftKeyboard());
        onView(withText(R.string.print)).perform(click());
        onView(withId(R.id.textview)).check(matches(withText("message => " + mExpectedString)));
    }
}

选择MainActivityTest，右键Run 'MainActivityTest'
手机屏幕就会看到被执行的动作，最后会看到as上输出测试结果。

6.PNG

https://google.github.io/android-testing-support-library/docs/espresso/setup/index.html

Addition

https://github.com/peace710/AgeraCore

Android单元测试