当自定义ImageView调用startAnimation(Animation)时,为什么getActivity()在JUnit测试期间会阻塞？

Question

我写了一个Android应用程序,显示一个自定义ImageView旋转自定义的自定义startAnimation(Animation).该应用程序工作正常,但如果我创建一个类型ActivityInstrumentationTestCase2和测试调用的JUnit测试getActivity(),该调用getActivity()永远不会返回,直到应用程序进入后台(例如,按下设备的主页按钮).

经过很长时间和挫折之后,我发现getActivity()如果我startAnimation(Animation)在自定义ImageView类中注释掉调用,则会立即返回.但这会破坏我的习惯的目的ImageView,因为我确实需要动画它.

任何人都可以告诉我为什么getActivity()在我的JUnit测试期间阻止但只有在startAnimation使用时？提前感谢任何能够建议解决方法或告诉我我做错了什么的人.

注意:解决方案需要至少使用Android API级别10.

以下是运行它所需的所有源代码(将任何PNG图像放在res/drawable中并将其命名为the_image.png):

activity_main.xml中:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <com.example.rotatingimageviewapp.RotatingImageView 
        android:id="@+id/rotatingImageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@drawable/the_image" />

</RelativeLayout>

MainActivity.java:

package com.example.rotatingimageviewapp;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;

public class MainActivity extends Activity {

    private RotatingImageView rotatingImageView = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        rotatingImageView = (RotatingImageView) findViewById(
                R.id.rotatingImageView);
        rotatingImageView.startRotation();
    }

    @Override
    protected void onPause() {
        super.onPause();
        rotatingImageView.stopRotation();
    }

    @Override
    protected void onResume() {
        super.onResume();
        rotatingImageView.startRotation();
    }

}

RotatingImageView.java(自定义ImageView):

package com.example.rotatingimageviewapp;

import java.util.Timer;
import java.util.TimerTask;

import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;

public class RotatingImageView extends ImageView {

    private static final long ANIMATION_PERIOD_MS = 1000 / 24;

    //The Handler that does the rotation animation
    private final Handler handler = new Handler() {

        private float currentAngle = 0f;
        private final Object animLock = new Object();
        private RotateAnimation anim = null;

        @Override
        public void handleMessage(Message msg) {
            float nextAngle = 360 - msg.getData().getFloat("rotation");
            synchronized (animLock) {
                anim = new RotateAnimation(
                        currentAngle,
                        nextAngle,
                        Animation.RELATIVE_TO_SELF,
                        .5f,
                        Animation.RELATIVE_TO_SELF,
                        .5f);
                anim.setDuration(ANIMATION_PERIOD_MS);
                /**
                 * Commenting out the following line allows getActivity() to
                 * return immediately!
                 */
                startAnimation(anim);
            }

            currentAngle = nextAngle;
        }

    };

    private float rotation = 0f;
    private final Timer timer = new Timer(true);
    private TimerTask timerTask = null;

    public RotatingImageView(Context context) {
        super(context);
    }

    public RotatingImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public RotatingImageView(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);
    }

    public void startRotation() {
        stopRotation();

        /**
         * Set up the task that calculates the rotation value
         * and tells the Handler to do the rotation
         */
        timerTask = new TimerTask() {

            @Override
            public void run() {
                //Calculate next rotation value
                rotation += 15f;
                while (rotation >= 360f) {
                    rotation -= 360f; 
                }

                //Tell the Handler to do the rotation
                Bundle bundle = new Bundle();
                bundle.putFloat("rotation", rotation);
                Message msg = new Message();
                msg.setData(bundle);
                handler.sendMessage(msg);
            }

        };
        timer.schedule(timerTask, 0, ANIMATION_PERIOD_MS);
    }

    public void stopRotation() {
        if (null != timerTask) {
            timerTask.cancel();
        }
    }

}

MainActivityTest.java:

package com.example.rotatingimageviewapp.test;

import android.app.Activity;
import android.test.ActivityInstrumentationTestCase2;

import com.example.rotatingimageviewapp.MainActivity;

public class MainActivityTest extends
        ActivityInstrumentationTestCase2<MainActivity> {

    public MainActivityTest() {
        super(MainActivity.class);
    }

    protected void setUp() throws Exception {
        super.setUp();
    }

    protected void tearDown() throws Exception {
        super.tearDown();
    }

    public void test001() {
        assertEquals(1 + 2, 3 + 0);
    }

    public void test002() {
        //Test hangs on the following line until app goes to background
        Activity activity = getActivity();
        assertNotNull(activity);
    }

    public void test003() {
        assertEquals(1 + 2, 3 + 0);
    }

}

Answer 1

不确定你们是否解决了这个问题.但这是我的解决方案,只需覆盖方法getActivity():

@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;
    }