测试活动是否返回预期结果

Question

我有以下活动：

package codeguru.startactivityforresult;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class ChildActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.child);

        this.resultButton = (Button) this.findViewById(R.id.result_button);
        this.resultButton.setOnClickListener(onResult);
    }

    private View.OnClickListener onResult = new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent result = new Intent();
            result.putExtra(ChildActivity.this.getString(R.string.result), ChildActivity.this.getResources().getInteger(R.integer.result));
            ChildActivity.this.setResult(RESULT_OK, result);
            ChildActivity.this.finish();
        }
    };
    private Button resultButton = null;
}

并进行以下JUnit测试：

package codeguru.startactivityforresult;

import android.app.Activity;
import android.test.ActivityInstrumentationTestCase2;
import android.test.UiThreadTest;
import android.widget.Button;
import junit.framework.Assert;

public class ChildActivityTest extends ActivityInstrumentationTestCase2<ChildActivity> {

    public ChildActivityTest() {
        super(ChildActivity.class);
    }

    @Override
    public void setUp() throws Exception {
        super.setUp();

        this.setActivityInitialTouchMode(false);

        this.activity = this.getActivity();
        this.resultButton = (Button) this.activity.findViewById(R.id.result_button);
    }

    @Override
    public void tearDown() throws Exception {
        super.tearDown();
    }

    @UiThreadTest
    public void testResultButtonOnClick() {
        Assert.assertTrue(this.resultButton.performClick());
        Assert.fail("How do I check the returned result?");
    }
    private Activity activity;
    private Button resultButton;
}

我如何确保单击按钮设置正确的结果（调用setResult()），该结果将返回到任何以此为起始的活动startActivityForResult()？

Answer 1

使用问题中的当前Activity实现，即，通过单击ChildActivity中的按钮设置结果，然后立即销毁该活动，在ChildActivityTest中我们无法做很多测试结果相关的东西。

相关问题测试onActivityResult（）的答案显示了如何在MainActivityTest中独立测试startActivityForResult（）和/或onActivityResult（）。通过独立方式，MainActivityTest不依赖于ChildActivity的交互，检测将捕获ChildActivity的创建并立即将其杀死，然后返回准备好的烘焙模拟ActivityResult，从而对MainActivity进行单元测试。

如果您不希望检测中断并返回模拟的ActivityResult，则可以让ChildActivity继续进行，然后在ChildActivity中模拟交互，然后将实际的ActivityResult返回给MainActivity。说如果您要MainActivity启动ChildActivity作为结果，然后更新TextView，以测试整个端到端的交互/合作，请参见下面的示例代码：

public class MainActivityTest extends ActivityInstrumentationTestCase2<MainActivity> {
  ... ...

  public void testStartActivityForResult() {
    MainActivity mainActivity = getActivity();
    assertNotNull(activity);

    // Check initial value in TextView:
    TextView text = (TextView) mainActivity.findViewById(com.example.R.id.textview1);
    assertEquals(text.getText(), "default vaule");

    try {
      Thread.sleep(2000);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }

    // Create an ActivityMonitor that monitor ChildActivity, do not interrupt, do not return mock result:
    Instrumentation.ActivityMonitor activityMonitor = getInstrumentation().addMonitor(ChildActivity.class.getName(), null , false);

    // Simulate a button click in MainActivity that start ChildActivity for result:
    final Button button = (Button) mainActivity.findViewById(com.example.R.id.button1);
    mainActivity.runOnUiThread(new Runnable() {
      public void run() {
        button.performClick();
      }
    });

    try {
      Thread.sleep(2000);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }

    getInstrumentation().waitForIdleSync();
    ChildActivity childActivity = (ChildActivity) getInstrumentation().waitForMonitorWithTimeout(activityMonitor, 5);
    // ChildActivity is created and gain focus on screen:
    assertNotNull(childActivity);

    // Simulate a button click in ChildActivity that set result and finish ChildActivity:
    final Button button2 = (Button) childActivity.findViewById(com.example.R.id.button1);
    childActivity.runOnUiThread(new Runnable() {
      public void run() {
        button2.performClick();
      }
    });

    try {
      Thread.sleep(2000);
    } catch (InterruptedException e) {
      e.printStackTrace();
    }

    getInstrumentation().waitForIdleSync();
    // TextView in MainActivity should be changed:
    assertEquals(text.getText(), "default value changed");
  }

  ... ...
}

我在这里添加了三个Thread.sleep（）调用，以便您有机会在运行JUnit Test时看到单击模拟的按钮。如您在这里看到的那样，一个独立的ChildActivityTest不足以测试整个合作，实际上我们是通过MainActivityTest间接测试ChildActivity.setResult（）的，因为我们从一开始就需要模拟整个交互。