Robotium中调用getActivity()方法导致程序挂起的研究浅析

发布时间：2020-07-02 04:21:02 作者：zhukev
来源：网络阅读：454

1. 问题背景描述

在工作中需要在没有项目源码的情况下直接使用robotium测试目标android平台launcher，平台的版本基于当前最新的android 4.4.2。之前在验证可行性的时候使用本人同样使用android4.4.2的测试手机htc incredable s针对一个只有apk的notepad应用做过同样的验证，在测试手机上运行完全没有问题。该测试代码如下：

package com.example.android.notepad.tryout;  import com.robotium.solo.Solo;  import android.test.ActivityInstrumentationTestCase2; import android.widget.TextView; import android.app.Activity;  @SuppressWarnings("rawtypes") public class NotePadTest extends ActivityInstrumentationTestCase2{  	private static Solo solo = null; 	public Activity activity; 	 	private static final int NUMBER_TOTAL_CASES = 2; 	private static int run = 0; 	 	private static Class<?> launchActivityClass; 	//对应re-sign.jar生成出来的信息框里的两个值 	private static String mainActiviy = "com.example.android.notepad.NotesList"; 	private static String packageName = "com.example.android.notepad";  	static {  		try {  			launchActivityClass = Class.forName(mainActiviy);  		} catch (ClassNotFoundException e) {  			throw new RuntimeException(e);  		}  	} 	 	 	@SuppressWarnings("unchecked") 	public NotePadTest() { 		super(packageName, launchActivityClass); 	}  	 	@Override 	public void setUp() throws Exception { 		//setUp() is run before a test case is started.  		//This is where the solo object is created. 		super.setUp();  		//The variable solo has to be static, since every time after a case's finished, this class TCCreateNote would be re-instantiated 		// which would lead to soto to re-instantiated to be null if it's not set as static 		//TextView title = (TextView)getActivity().findViewById(Ref.id.title); 		 		if(solo == null) { 			 			NotePadTest.solo = new Solo(getInstrumentation(),getActivity()); 			 		} 	} 	 	@Override 	public void tearDown() throws Exception { 		//Check whether it's the last case executed. 		run += countTestCases(); 		if(run >= NUMBER_TOTAL_CASES) { 			solo.finishOpenedActivities(); 		} 	}  	public void testAddNoteCNTitle() throws Exception { 		//Thread.sleep(5000); 		solo.clickOnMenuItem("Add note"); 		solo.enterText(0, "中文标签笔记"); 		solo.clickOnMenuItem("Save"); 		solo.clickInList(0); 		solo.clearEditText(0); 		solo.enterText(0, "Text 1"); 		solo.clickOnMenuItem("Save"); 		solo.assertCurrentActivity("Expected NotesList Activity", "NotesList"); 		 		solo.clickLongOnText("中文标签笔记"); 		solo.clickOnText("Delete"); 		 		 	} 	 	 	public void testAddNoteEngTitle() throws Exception { 		solo.clickOnMenuItem("Add note"); 		solo.enterText(0, "English Title Note"); 		solo.clickOnMenuItem("Save"); 		solo.clickInList(0); 		solo.clearEditText(0); 		solo.enterText(0, "Text 1"); 		solo.clickOnMenuItem("Save"); 		solo.assertCurrentActivity("Expected NotesList Activity", "NotesList"); 		 		solo.clickLongOnText("English Title Note"); 		solo.clickOnText("Delete"); 	} }

但在工作的测试目标平台launcher中使用同样的方法去setup并运行简单的测试时碰到问题：测试程序一直挂起没有返回，程序挂起在以下getaActivity()方法（因是公司代码，故以notepad测试代码取代之）：

	@Override 	public void setUp() throws Exception { 		//setUp() is run before a test case is started.  		//This is where the solo object is created. 		super.setUp();  		//The variable solo has to be static, since every time after a case's finished, this class TCCreateNote would be re-instantiated 		// which would lead to soto to re-instantiated to be null if it's not set as static 		 		if(solo == null) {		 			NotePadTest.solo = new Solo(getInstrumentation(),getActivity());	 		} 	}

当时一直怀疑是否系统launcher的robotium初始化和setup方法跟普通的apk不一样，google上有历史文章描述getActivity()在Android 2.xx.xx上确实有这个问题，但后来的版本已经解决，而本人使用的时当前最的4.4.2，所以不应该还存在这种问题。针对这个思路去尝试找解决办法终无果。

2.问题分析

既然是getActvity()方法出现问题，而该方法原有的bug也已经在最新的版本fixed，在google无所获的情况下也只能剩下分析源码这条路了。因为是自己刚在backbook上搭建的自动化研究平台，为了节省时间，当时没有下载android的相应源码，只有sdk，所以第一步必须是先在项目中配置使用上android的源码，其理与配置javadoc相近，请查看本人之前的一篇文章《How to Configure Javadoc for Robotium Library》，这里不做累术。

加入源码后调试分析，最终程序挂起在android.test.InstrumentationTestCase中的launchActivityWithIntent方法中,以下是eclipse中的调试截图示例：

以下是该方法的完整代码片段：

/**      * Utility method for launching an activity with a specific Intent.      *       * <p><b>NOTE:</b> The parameter <i>pkg</i> must refer to the package identifier of the      * package hosting the activity to be launched, which is specified in the AndroidManifest.xml      * file.  This is not necessarily the same as the java package name.      *      * @param pkg The package hosting the activity to be launched.      * @param activityCls The activity class to launch.      * @param intent The intent to launch with      * @return The activity, or null if non launched.      */     @SuppressWarnings("unchecked")     public final <T extends Activity> T launchActivityWithIntent(             String pkg,             Class<T> activityCls,             Intent intent) {         intent.setClassName(pkg, activityCls.getName());         intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);         T activity = (T) getInstrumentation().startActivitySync(intent);         getInstrumentation().waitForIdleSync();         return activity;     }

导致挂起的位置是里面的getInstrumentation().waitForIdleSync()方法，到了这里再代码跟踪进去看到的就是android.app.instrumentation这个基类里面:

    /**      * Synchronously wait for the application to be idle.  Can not be called      * from the main application thread -- use {@link #start} to execute      * instrumentation in its own thread.      */     public void waitForIdleSync() {         validateNotAppThread();         Idler idler = new Idler(null);         mMessageQueue.addIdleHandler(idler);         mThread.getHandler().post(new EmptyRunnable());         idler.waitForIdle();     }

这里按照本人的理解做的事情大概如下：

首先确保调用这个方法的来源不是application的主线程
然后把当前等待application变成idle的请求放到消息队列中
最后等待app在处理完所有事件达到idle状态的时候返回

看到这里我幡然领悟，在目标平台上面我们有一个天气预报的功能，在不停的发送事件给application（也就是launcher）来更新当前的天气情况，所以一直没有达到idle的状态，这样这个函数也就一直没有返回而挂起了。而在本人的测试手机上测试的notepad这个apk，一进去的launchable activity就是idle的，所以不会碰到这个问题。

带着这个思路在调整google关键字在stackoverflow中找到了国外同行碰到的一个类似的问题：http://stackoverflow.com/questions/20860832/why-does-getactivity-block-during-junit-test-when-custom-imageview-calls-start

这里总结下本人研究过程中了解到的robotium初始化solo的时候new Solo(getInstrumentation(),getActivity())中getActivity所做的事情：

如果目标activity没有起来，那么启动该activity并放在前台
如果目标activity已经起来，那么直接放在前台等待被测试
如果该该activity所属application在自动不停的接受事件，直接调用getActivity会因为一直等待application变成idle状态而挂起

3. 解决方法

本人按照项目中的目标测试launcher的实际情况想到的解决方法是在初始化solo的时候不去调用getActivity()这个InstrumentationTestCase2的方法：

solo = new Solo(getInstrumentation());

因为我们的launcher在robotium在kill掉原来的launcher进程的时候就会自动起来，所以并不需要手动的去getActivity()去启动。这种方法在不能启动起来的apk如notepad上面就不行，不信你去掉getActivity()的调用，保证notepad不会启动或者放到前台。但是如果你在开始测试前先把notepad手动起来并放到前台，测试还是会正常进行的。比如以下的验证性代码：

package com.example.android.notepad.tryout;  import com.robotium.solo.Solo;  import android.test.ActivityInstrumentationTestCase2; import android.widget.TextView; import android.app.Activity;  @SuppressWarnings("rawtypes") public class NotePadTest extends ActivityInstrumentationTestCase2{  	private static Solo solo = null; 	public Activity activity; 	 	private static final int NUMBER_TOTAL_CASES = 2; 	private static int run = 0; 	 	private static Class<?> launchActivityClass; 	//对应re-sign.jar生成出来的信息框里的两个值 	private static String mainActiviy = "com.example.android.notepad.NotesList"; 	private static String packageName = "com.example.android.notepad";  	static {  		try {  			launchActivityClass = Class.forName(mainActiviy);  		} catch (ClassNotFoundException e) {  			throw new RuntimeException(e);  		}  	} 	 	 	@SuppressWarnings("unchecked") 	public NotePadTest() { 		super(packageName, launchActivityClass); 	}  	 	@Override 	public void setUp() throws Exception { 		//setUp() is run before a test case is started.  		//This is where the solo object is created. 		super.setUp();  		//The variable solo has to be static, since every time after a case's finished, this class TCCreateNote would be re-instantiated 		// which would lead to soto to re-instantiated to be null if it's not set as static 		//TextView title = (TextView)getActivity().findViewById(Ref.id.title); 		 		if(solo == null) { 			 			NotePadTest.solo = new Solo(getInstrumentation());//, getActivity()); 			 		} 	} 	 	@Override 	public void tearDown() throws Exception { 		//Check whether it's the last case executed. 		run += countTestCases(); 		if(run >= NUMBER_TOTAL_CASES) { 			solo.finishOpenedActivities(); 		} 	}  	public void testAddNoteCNTitle() throws Exception { 		//getActivity(); 		Thread.sleep(5000); 		solo.clickOnMenuItem("Add note"); 		solo.enterText(0, "中文标签笔记"); 		solo.clickOnMenuItem("Save"); 		solo.clickInList(0); 		solo.clearEditText(0); 		solo.enterText(0, "Text 1"); 		solo.clickOnMenuItem("Save"); 		solo.assertCurrentActivity("Expected NotesList Activity", "NotesList"); 		 		solo.clickLongOnText("中文标签笔记"); 		solo.clickOnText("Delete"); 		 		 	} }

初始化solo的时候和testcase里面都没有去调用getActivity(),但是在testcase开始前先睡眠5秒，如果在这5秒的过程中你手动把notepad给启动起来，那么睡眠时间过后测试会继续正常运行。

刚才stackoverflow上提到的另外一个方法是重写getActivity()这个IntrumentationTestCase2的方法（注意我们所有的robotium测试类都是继承于该class的):

@Override     public MyActivity getActivity() {         if (mActivity == null) {             Intent intent = new Intent(getInstrumentation().getTargetContext(), MyActivity.class);             intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);             // register activity that need to be monitored.             monitor = getInstrumentation().addMonitor(MyActivity.class.getName(), null, false);             getInstrumentation().getTargetContext().startActivity(intent);             mActivity = (MyActivity) getInstrumentation().waitForMonitor(monitor);             setActivity(mActivity);         }         return mActivity;     }

鉴于本人现在只是做前期的可行×××，够用就好，且周末手头上也没有目标机器在手进行验证，所以有兴趣的朋友就自己去尝试下吧，

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Robotium中调用getActivity()方法导致程序挂起的研究浅析

Robotium中调用getActivity()方法导致程序挂起的研究浅析

1. 问题背景描述

2.问题分析

3. 解决方法

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