在Android上实现Junit单元测试的四部曲

第一步：新建一个TestCase，记得要继承androidTestCase，才能有getContext()来获取当前的上下文变量，这在Android测试中很重要的，因为很多的Android api都需要context。

Java代码

public class TestMath extends AndroidTestCase {    
        
    private int i1;    
    private int i2;    
    static final String LOG_TAG = "MathTest";    
        
    @Override    
    protected void setUp() throws Exception {    
        i1 = 2;    
        i2 = 3;    
    }    
        
    public void testAdd() {    
        assertTrue("testAdd failed", ((i1 + i2) == 5));    
    }    
        
    public void testDec() {    
        assertTrue("testDec failed", ((i2 - i1) == 1));    
    }    
    
    @Override    
    protected void tearDown() throws Exception {    
        super.tearDown();    
    }    
    
    @Override    
    public void testAndroidTestCaseSetupProperly() {    
        super.testAndroidTestCaseSetupProperly();    
        //Log.d( LOG_TAG, "testAndroidTestCaseSetupProperly" );    
    }    
    
}

第二步：新建一个TestSuit，这个就继承Junit的TestSuite就可以了，注意这里是用的addTestSuite方法，一开始使用addTest方法就是不能成功。

Java代码

public class ExampleSuite extends TestSuite {    
        
    public ExampleSuite() {    
        addTestSuite(TestMath.class);    
    }    
    
}

第三步：新建一个Activity，用来启动单元测试，并显示测试结果。系统的AndroidTestRunner竟然什么连个UI界面也没有实现，这里只是最简单的实现了一个

Java代码

public class TestActivity extends Activity {    
        
    private TextView resultView;    
        
    private TextView barView;    
        
    private TextView messageView;    
        
    private Thread testRunnerThread;    
        
    private static final int SHOW_RESULT = 0;    
        
    private static final int ERROR_FIND = 1;    
    
    @Override    
    protected void onCreate(Bundle savedInstanceState) {    
        super.onCreate(savedInstanceState);    
        setContentView(R.layout.main);    
        resultView = (TextView)findViewById(R.id.ResultView);    
        barView = (TextView)findViewById(R.id.BarView);    
        messageView = (TextView)findViewById(R.id.MessageView);    
        Button lunch = (Button)findViewById(R.id.LunchButton);    
        lunch.setOnClickListener(new View.OnClickListener() {    
            @Override    
            public void onClick(View v) {    
                startTest();    
            }    
        });    
    }    
        
    private void showMessage(String message) {    
        hander.sendMessage(hander.obtainMessage(ERROR_FIND, message));    
    }    
        
    private void showResult(String text) {    
        hander.sendMessage(hander.obtainMessage(SHOW_RESULT, text));    
    }    
        
    private synchronized void startTest() {    
        if (testRunnerThread != null    
                && testRunnerThread.isAlive()) {    
            testRunnerThread = null;    
        }    
        if (testRunnerThread == null) {    
            testRunnerThread = new Thread(new TestRunner(this));    
            testRunnerThread.start();    
        } else {    
            Toast.makeText(this,     
                    "Test is still running",     
                    Toast.LENGTH_SHORT).show();    
        }    
    }    
        
    public Handler hander = new Handler() {    
        public void handleMessage(Message msg) {    
            switch (msg.what) {    
                case SHOW_RESULT:    
                    resultView.setText(msg.obj.toString());    
                    break;    
                case ERROR_FIND:    
                    messageView.append(msg.obj.toString());    
                    barView.setBackgroundColor(Color.RED);    
                    break;    
                default:    
                    break;    
            }    
        }    
    };    
        
    class TestRunner implements Runnable, TestListener {    
        
        private Activity parentActivity;    
            
        private int testCount;    
            
        private int errorCount;    
            
        private int failureCount;    
            
        public TestRunner(Activity parentActivity) {    
            this.parentActivity = parentActivity;    
        }    
    
        @Override    
        public void run() {    
            testCount = 0;    
            errorCount = 0;    
            failureCount = 0;    
                
            ExampleSuite suite = new ExampleSuite();    
            AndroidTestRunner testRunner = new AndroidTestRunner();    
            testRunner.setTest(suite);    
            testRunner.addTestListener(this);    
            testRunner.setContext(parentActivity);    
            testRunner.runTest();    
        }    
    
        @Override    
        public void addError(Test test, Throwable t) {    
            errorCount++;    
            showMessage(t.getMessage() + "\n");    
        }    
    
        @Override    
        public void addFailure(Test test, AssertionFailedError t) {    
            failureCount++;    
            showMessage(t.getMessage() + "\n");    
        }    
    
        @Override    
        public void endTest(Test test) {    
            showResult(getResult());    
        }    
    
        @Override    
        public void startTest(Test test) {    
            testCount++;    
        }    
            
        private String getResult() {    
            int successCount = testCount - failureCount - errorCount;    
            return "Test:" + testCount + " Success:" + successCount + " Failed:" + failureCount + " Error:" + errorCount;    
        }    
            
    }    
    
}

第四步：修改AndroidManifest.xml,加入，不然会提示找不到AndroidTestRunner，这里需要注意是这句话是放在applications下面的，我一开始也不知道，放错了地方，浪费了不少时间

Xml代码

xml version="1.0" encoding="utf-8"?>      
<manifest xmlns:Android="http://schemas.Android.com/apk/res/Android"      
      package="com.test.sample"      
      Android:versionCode="1"      
      Android:versionName="1.0">      
    <application Android:icon="@drawable/icon" Android:label="@string/app_name" Android:debuggable="true">      
        <activity Android:name=".TestActivity"      
                  Android:label="@string/app_name">      
            <intent-filter>      
                <action Android:name="Android.intent.action.MAIN" />      
                <category Android:name="Android.intent.category.LAUNCHER" />      
            intent-filter>      
        activity>      
    <uses-library Android:name="Android.test.runner" />      
    application>      
    <uses-sdk Android:minSdkVersion="4" />      
manifest>