基于Espresso的Android UI自动化框架设计之三

Page Object Model Design Pattern (页面对象模型设计模式) , 这种模型很大程度的增强了方法的复用 , 使测试代码的可读性和层次感也得到了明显的优化.

本系列项目位于github: https://github.com/rawqing/EspressoBlackBoxDemo

POM 模式的基本理论这里就不讲了 , 大家课参考 Design Patterns in Test Automation I 虽然不是说的Espresso,但基本原理都是一样的 .

一. 在此之前

虽然 espresso 的api已经封装得很好了, 但为了更好的使用 , 我们还是需要对其进行二次封装.

获取 ActivityTestRule
黑盒测试获取 ActivityTestRule 只有通过反射的方式 , 但也不能每一个测试类都使用 Class.forName(className) . 并且 kotlin 对泛型的要求比较严格 , so ,这里我们使用 java 进行反射封装:

public static ActivityTestRule getActivityTestRule(String activityName) {
    return new ActivityTestRule(getFixedClass(activityName));
}

/**
 * 返回给定全类名的Class对象 (已处理异常)
 * @param className
 * @return
 */
public static Class<?> getFixedClass(String className){
    try {
        return Class.forName(className);
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    }
    return null;
}

封装 ViewElement
这是对 ViewInteraction 的二次封装 (这里只示例简单封装)

package yq.test.espressoblackboxdemo.expansions
   
import android.support.test.espresso.Espresso.onView
import android.support.test.espresso.ViewAssertion
import android.support.test.espresso.ViewInteraction
import android.support.test.espresso.action.ViewActions
import android.support.test.espresso.matcher.RootMatchers
import android.support.test.espresso.matcher.ViewMatchers.*
import android.support.test.rule.ActivityTestRule
import android.view.View
import org.hamcrest.Matcher
import org.hamcrest.Matchers
import org.hamcrest.Matchers.allOf
   
class ViewElement(
        private var id: String? = null,
   
        private var text: String? = null,
   
        private var isToast: Boolean = false,
   
        private var atr: ActivityTestRule<*>? = null,
   
        private var children: MutableList<ViewElement> = ArrayList()
) {
   
    private var interaction : ViewInteraction? = null
   
    /** View 查找部分 **/
   
    /**
     * 将 ViewElement 中的成员属性转换成 Matcher<View>
     *     这是关键的方法
     */
    private fun way(): Matcher<View> {
        val list = ArrayList<Matcher<View>>()
   
        id?.let { list.add(withResourceName(it)) }
        text?.let { list.add(withText(it)) }
        children.let { it.forEach {el-> list.add(withChild(el.way())) } }
   
        return allOf(list)
    }
   
    /**
     * 创建 ViewInteraction 实例 
     * 将区分 toast 和 普通 View
     */
    private fun createInteraction(): ViewInteraction? {
        if (interaction == null)
            interaction = if (isToast) {
                onView(this.way())
                        .inRoot(RootMatchers.withDecorView(Matchers.not<View>(Matchers.`is`<View>(atr!!.activity.window.decorView))))
            } else {
                onView(this.way())
            }
        return interaction
    }
   
    /** 二次封装部分 **/
   
    fun replaceText(text: String): ViewElement {
        this.createInteraction()?.perform(ViewActions.replaceText(text))
        return this
    }
   
    fun click(): ViewElement {
        this.createInteraction()?.perform(ViewActions.click())
        return this
    }
   
   
    fun check(viewAssertion: ViewAssertion): ViewElement {
        this.createInteraction()?.check(viewAssertion)
        return this
    }
   
    /** setter **/
   
    fun setId(id: String): ViewElement {
        this.id = id
        return this
    }
   
    fun setText(text: String): ViewElement {
        this.text = text
        return this
    }
   
    fun setChildren(vararg children: ViewElement): ViewElement {
        this.children = children.toMutableList()
        return this
    }
   
    fun beToast(isToast: Boolean): ViewElement {
        this.isToast = isToast
        return this
    }
   
    fun setActivityTestRule(atr: ActivityTestRule<*>?): ViewElement {
        this.atr = atr
        return this
    }
}

二.分层设计

先来看一下目录结构

View 层 (Page Object)

 package yq.test.espressoblackboxdemo.views
    
 import android.support.test.espresso.assertion.ViewAssertions.matches
 import android.support.test.espresso.matcher.ViewMatchers.isDisplayed
 import android.support.test.rule.ActivityTestRule
 import yq.test.espressoblackboxdemo.expansions.ViewElement
    
 class LoginView {
    
     private val email = ViewElement().setId("email")
     private val password = ViewElement("password")
     private val loginBtn = ViewElement(id = "email_sign_in_button")
    
     /**
      * 执行登录
      */
     fun doLogin(emailText: String, pwd: String): LoginView {
         email.replaceText(emailText)
         password.replaceText(pwd)
         loginBtn.click()
    
         return this
     }
    
     /**
      * 检查登录错误时的错误提示
      */
     fun checkLoginError(toastMsg: String ,atr: ActivityTestRule<*>): LoginView {
         ViewElement(text = toastMsg, isToast = true ,atr = atr)
                 .check(matches(isDisplayed()))
          return this
     }
 }

这里还嵌入了 链式调用模式 . Page 中的每个方法都带上 return this ,当然如果是登录成功了 , 那么就应该 return AccountView 或者是其他登录成功后应当展示的 Activity View .

Tests 层, 也就是具体的 test case

package yq.test.espressoblackboxdemo.tests
   
import android.support.test.runner.AndroidJUnit4
import org.junit.Test
import org.junit.runner.RunWith
import org.junit.Rule
import yq.test.espressoblackboxdemo.utils.UtilJ.getActivityTestRule
import yq.test.espressoblackboxdemo.views.LoginView
   
@RunWith(AndroidJUnit4::class)
class LoginTest {
   
    @get:Rule
    var atr = getActivityTestRule("yq.test.logindemo.LoginActivity")
   
   
    @Test
    fun loginTest(){
        val login = LoginView()
        login
                .doLogin("hello" ,"")
                .checkLoginError("This email address is invalid" ,atr)
    }
}

运行结果

三. 总结

POM 到这里就结束了 . 到目前, 我们总共也只分了两层(扩展和工具类不算在分层架构里面). 当然 , 还有 data层 我们目前还没有涉及 ,这将在后面的 数据驱动 章节讲述

架构基础 -- POM设计模式

一. 在此之前

二.分层设计

三. 总结