上一篇文章：
Android自动化测试--Instrumented Unit Tests使用
相比上一篇文章所讲的Instrumented Unit Tests，本文所讲的自动化测试Espresso最显著的特点就是，可以与UI相交互。
使用
首先我们在Android Studio中新建一个项目，取名为EspressoTests。同时删除自动生成的一些文件，最终目录结构如下：
目录结构
接下来我们看看如何一步一步的使用Espresso，首先在�根目录的 build.gradle 文件中添加下面的引入。
ext {
buildToolsVersion = "24.0.1"
supportLibVersion = "24.2.0"
espressoVersion = "2.2.2"
}
在app目录中的build.gradle 文件中添加下面的引入，根据提示点击Sync Now。
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
// App dependencies
compile 'com.android.support:appcompat-v7:' + rootProject.supportLibVersion;
compile 'com.android.support:support-annotations:' + rootProject.supportLibVersion;
compile 'com.android.support:recyclerview-v7:' + rootProject.supportLibVersion;
androidTestCompile 'com.android.support.test.espresso:espresso-core:' + rootProject.espressoVersion;
androidTestCompile('com.android.support.test.espresso:espresso-contrib:' + rootProject.espressoVersion) {
transitive false
};
androidTestCompile 'com.android.support.test.espresso:espresso-web:' + rootProject.espressoVersion;
androidTestCompile 'com.android.support:support-annotations:' + rootProject.supportLibVersion;
androidTestCompile 'com.android.support:recyclerview-v7:' + rootProject.supportLibVersion;
}
接下来我们编写测试例子，最终的结果如下：
Paste_Image.png
其中MainActivity界面如下，输入框中点击数字后点击计算可以在结果处显示两者相加的值，点击webview跳转到WebViewActivity，点击recycleview跳转到RecycleViewActivity。
MainActivity
其中WebViewActivity中包含一个webview，可以加载跳转传过来的url。
WebViewActivity
其中RecycleViewActivity就是一个recycleview的简单使用，实现了一个列表。
RecycleViewActivity
接下来我们看看测试的代码，在代码中又详细的注释。
package me.shihao.instrumentedunittests;
import android.support.test.espresso.Espresso;
import android.support.test.espresso.contrib.RecyclerViewActions;
import android.support.test.espresso.matcher.ViewMatchers;
import android.support.test.espresso.web.assertion.WebViewAssertions;
import android.support.test.espresso.web.webdriver.DriverAtoms;
import android.support.test.espresso.web.webdriver.Locator;
import android.support.test.rule.ActivityTestRule;
import android.support.test.runner.AndroidJUnit4;
import org.hamcrest.Matchers;
import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;
import me.shihao.espressotests.MainActivity;
import me.shihao.espressotests.R;
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.isDisplayed;
import static android.support.test.espresso.matcher.ViewMatchers.withId;
import static android.support.test.espresso.matcher.ViewMatchers.withText;
import static android.support.test.espresso.web.sugar.Web.onWebView;
import static android.support.test.espresso.web.webdriver.DriverAtoms.findElement;
import static android.support.test.espresso.web.webdriver.DriverAtoms.webClick;
/**
* Created by shihao on 2017/3/2.
*/
@RunWith(AndroidJUnit4.class)
public class MainActivityTest {
@Rule
public ActivityTestRule activityTestRule = new ActivityTestRule(MainActivity.class);
@Test
public void test() {
//通过id找到edittext，在里面输入2并关闭输入法
Espresso.onView(withId(R.id.editText)).perform(typeText("2"), closeSoftKeyboard());
//通过id找到edittext，在里面输入5并关闭输入法
Espresso.onView(withId(R.id.editText2)).perform(typeText("5"), closeSoftKeyboard());
//通过id找到button，执行点击事件
Espresso.onView(withId(R.id.button)).perform(click());
//通过id找到textview，并判断是否与文本匹配
Espresso.onView(withId(R.id.textView)).check(matches(withText("计算结果：6")));
Espresso.onView(withId(R.id.textView)).check(matches(withText("计算结果：7")));
}
@Test
public void testRecycleView() {
//通过文本RecycleView找到按钮，并执行点击事件，跳转到RecycleviewActivity
Espresso.onView(withText("RecycleView")).perform(click());
//通过文本"Item 0"找到view，并检查是否显示，然后执行点击事件 ，此时会弹出对话框
Espresso.onView(withText("Item 0")).check(matches(isDisplayed())).perform(click());
//通过文本"确定"找到对话框上的确定按钮，执行点击事件，关闭对话框
Espresso.onView(withText("确定")).perform(click());
//通过文本"Item 2"找到view，并检查是否显示，然后执行点击事件，此时会弹出对话框
Espresso.onView(withText("Item 2")).check(matches(isDisplayed())).perform(click());
//执行点击返回按钮事件，关闭对话框
Espresso.pressBack();
//通过id找到recycleview，然后执行滑动事件，滑动到21项
Espresso.onView(ViewMatchers.withId(R.id.recycleview)).perform(RecyclerViewActions.scrollToPosition(21));
//通过文本"Item 20"找到view，并检查是否显示，然后执行点击事件，此时会弹出对话框
Espresso.onView(withText("Item 20")).check(matches(isDisplayed())).perform(click());
//通过文本"确定"找到对话框上的确定按钮，执行点击事件，关闭对话框
Espresso.onView(withText("确定")).perform(click());
//执行点击返回按钮事件，关闭跳转到RecycleviewActivity
Espresso.pressBack();
}
@Test
public void testWebView() {
//通过文本RecycleView找到按钮，并执行点击事件，跳转到WebViewActivity
Espresso.onView(withText("WebView")).perform(click());
//通过name为"word"找到搜索输入框
onWebView().withElement(findElement(Locator.NAME, "word"))
//往输入框中输入字符串"android"
.perform(DriverAtoms.webKeys("android"))
//通过id为"index-bn"找到"百度一下"按钮
.withElement(DriverAtoms.findElement(Locator.ID, "index-bn"))
//执行点击事件
.perform(webClick())
//通过id为"results"找到结果div
.withElement(DriverAtoms.findElement(Locator.ID, "results"))
//检查div中是否包含字符串"android"
.check(WebViewAssertions.webMatches(DriverAtoms.getText(), Matchers.containsString("android")));
//执行点击返回按钮事件，关闭跳转到WebViewActivity
Espresso.pressBack();
}
}
package me.shihao.instrumentedunittests;
import android.content.Intent;
import android.support.test.espresso.web.action.AtomAction;
import android.support.test.espresso.web.assertion.WebViewAssertions;
import android.support.test.espresso.web.sugar.Web;
import android.support.test.espresso.web.webdriver.DriverAtoms;
import android.support.test.espresso.web.webdriver.Locator;
import android.support.test.rule.ActivityTestRule;
import android.support.test.runner.AndroidJUnit4;
import org.hamcrest.Matchers;
import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;
import me.shihao.espressotests.WebViewActivity;
import static android.support.test.espresso.web.sugar.Web.onWebView;
import static android.support.test.espresso.web.webdriver.DriverAtoms.findElement;
import static android.support.test.espresso.web.webdriver.DriverAtoms.webClick;
import static org.hamcrest.Matchers.containsString;
/**
* Created by shihao on 2017/3/3.
*/
@RunWith(AndroidJUnit4.class)
public class WebViewActivityTest {
@Rule
public ActivityTestRule activityTestRule = new ActivityTestRule(WebViewActivity.class, false);
@Test
public void test() {
//传递数据到WebViewActivity
Intent intent = new Intent();
intent.putExtra(WebViewActivity.EXTRA_URL, "http://m.baidu.com");
activityTestRule.launchActivity(intent);
//通过name为"word"找到搜索输入框
onWebView().withElement(findElement(Locator.NAME, "word"))
//往输入框中输入字符串"android"
.perform(DriverAtoms.webKeys("android"))
//通过id为"index-bn"找到"百度一下"按钮
.withElement(DriverAtoms.findElement(Locator.ID, "index-bn"))
//执行点击事件
.perform(webClick())
//通过id为"results"找到结果div
.withElement(DriverAtoms.findElement(Locator.ID, "results"))
//检查div中是否包含字符串"android"
.check(WebViewAssertions.webMatches(DriverAtoms.getText(), Matchers.containsString("android")));
}
}
接下来我们运行测试一下MainActivityTest，看看效果如何
测试结果
测试结果与我们预期的一样，有一个不匹配。手机运行效果如下：
运行效果.gif
接下来我们就看一看如何在测试中与多个应用界面相交互，欢迎查看下一篇文章：