我是 Android 上的 Espresso 的新手，我遇到了以下问题: 我希望 Espresso 在按钮上执行长按(或其他操作)，当按钮一直被按下时，我想检查不同 View 的状态。

在(或多或少)伪代码中:

onView(withId(button_id)).perform(pressButtonDown());
onView(withId(textBox_id)).check(matches(withText("Button is pressed")));
onView(withId(button_id)).perform(releaseButton());

我尝试使用 MotionEvents.sendDown() 和 .sendUp() 编写 2 个自定义点击，PRESS 和 RELEASE，但没有成功。 如果这是正确的路径，我可以发布目前为止得到的代码。

编辑:

public class PressViewActions
{
    public static ViewAction pressDown(){
        return new GeneralClickAction(HoldTap.DOWN, GeneralLocation.CENTER, Press.THUMB);
    }

    public static ViewAction release() {
        return new GeneralClickAction(HoldTap.UP, GeneralLocation.CENTER, Press.THUMB);
    }
}

以及 Tappers 的代码:

public enum HoldTap implements Tapper {

    DOWN {
        @Override
        public Tapper.Status sendTap(UiController uiController, float[] coordinates, float[] precision)
        {
            checkNotNull(uiController);
            checkNotNull(coordinates);
            checkNotNull(precision);

            DownResultHolder res = MotionEvents.sendDown(uiController, coordinates, precision);

            ResultHolder.setController(uiController);
            ResultHolder.setResult(res);

            return Status.SUCCESS;
        }
    },

    UP{
        @Override
        public Tapper.Status sendTap(UiController uiController, float[] coordinates, float[] precision)
        {
            DownResultHolder res = ResultHolder.getResult();
            UiController controller = ResultHolder.getController();

            try {
                if(!MotionEvents.sendUp(controller, res.down))
                {
                    MotionEvents.sendCancel(controller, res.down);
                    return Status.FAILURE;
                }

            }
            finally {
                //res.down.recycle();
            }

            return Status.SUCCESS;
        }
    }
}

我得到的错误如下:

android.support.test.espresso.PerformException: Error performing 'up click' on view 'with id: de.test.app:id/key_ptt'.
...
...
Caused by: java.lang.RuntimeException: Couldn't click at: 281.5,1117.5 precision: 25.0, 25.0 . Tapper: UP coordinate provider: CENTER precision describer: THUMB. Tried 3 times. With Rollback? false

希望对您有所帮助。

我们将不胜感激任何帮助和想法!

提前很多坦克!

最佳答案

Android 中的点击由两个事件组成，一个按下事件和一个向上/取消事件。如果您想将这两者分开，则不能进行“点击”，因为它们已经包含了两者。

也就是说，您的想法可行，您只需要使用一个较低级别的 API，即 UiController 以及 MotionEvents 中的辅助方法。不过请注意:由于“释放” View 需要先保留它，如果您不进行适当的清理，您的测试将相互依赖。

示例:在一个测试中，您按下了一个 View ，测试失败了，然后在另一个测试中，您释放了一个您没有点击的 View :您的第二个测试本不应该通过。

我上传于 my github一个完整的样本。这里是要点。先上测试代码:

@Before
public void setUp() throws Exception {
    super.setUp();
    injectInstrumentation(InstrumentationRegistry.getInstrumentation());
    getActivity();
}

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

@Test
public void testAssertWhilePressed() {
    onView(withId(R.id.button)).perform(pressAndHold());
    onView(withId(R.id.text)).check(matches(withText("Button is held down")));
    onView(withId(R.id.button)).perform(release());
}

然后是 LowLevelActions:

public class LowLevelActions {
    static MotionEvent sMotionEventDownHeldView = null;

    public static PressAndHoldAction pressAndHold() {
        return new PressAndHoldAction();
    }

    public static ReleaseAction release() {
        return new ReleaseAction();
    }

    public static void tearDown() {
        sMotionEventDownHeldView = null;
    }

    static class PressAndHoldAction implements ViewAction {
        @Override
        public Matcher<View> getConstraints() {
            return isDisplayingAtLeast(90); // Like GeneralClickAction
        }

        @Override
        public String getDescription() {
            return "Press and hold action";
        }

        @Override
        public void perform(final UiController uiController, final View view) {
            if (sMotionEventDownHeldView != null) {
                throw new AssertionError("Only one view can be held at a time");
            }

            float[] precision = Press.FINGER.describePrecision();
            float[] coords = GeneralLocation.CENTER.calculateCoordinates(view);
            sMotionEventDownHeldView = MotionEvents.sendDown(uiController, coords, precision).down;
            // TODO: save view information and make sure release() is on same view
        }
    }

    static class ReleaseAction implements ViewAction {
        @Override
        public Matcher<View> getConstraints() {
            return isDisplayingAtLeast(90);  // Like GeneralClickAction
        }

        @Override
        public String getDescription() {
            return "Release action";
        }

        @Override
        public void perform(final UiController uiController, final View view) {
            if (sMotionEventDownHeldView == null) {
                throw new AssertionError("Before calling release(), you must call pressAndHold() on a view");
            }

            float[] coords = GeneralLocation.CENTER.calculateCoordinates(view);
            MotionEvents.sendUp(uiController, sMotionEventDownHeldView, coords);
        }
    }
}

关于安卓 Espresso : Make assertion while button is kept pressed，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/32010927/