Android-测试启动未知外部活动的意图

Question

我有一个活动，在单击按钮时会启动一个外部活动。外部活动是根据操作启动的，活动名称及其包名称未知。我尝试使用Espresso来模拟这种意图，但这种方法不起作用，并且测试失败。

MyActivity.java

@Override
public void onCreate(final Bundle savedInstanceState) {
    mLaunchButton = (Button) findViewById(R.id.launch_button);
    mLaunchButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(final View v) {
                Log.i(TAG, "Launch button clicked.");
                startActivity(new Intent("action_string"));
            }
        });
}

MyActivityTest.java

@Rule
    public IntentsTestRule<MyActivity> mIntentRule =
            new IntentsTestRule<>(MyActivity.class);
@Test
    public void testActivity() {
        onView(withId(R.id.launch_button)).perform(click());
        intended(hasAction("action_string"));
    }

错误

android.support.test.espresso.PerformException: Error performing 'single click - At Coordinates: 391, 715 and precision: 16, 16' on view 'with id: com.domain.myapp:id/launch_button'.
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Caused by: android.content.ActivityNotFoundException: No Activity found to handle Intent { act=action_string (has extras) }
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