如何在Espresso的RatingBar上设置特定评级？

Question

我正在尝试编写一个测试RatingBar选择的Espresso测试。 如何使用Espresso设置特定评级？ 我只看到click() ，它总是设置中等评级。

Answer 1

接受的答案帮助我编写了以下自定义ViewAction：

public final class SetRating implements ViewAction {

    @Override
    public Matcher<View> getConstraints() {
        Matcher <View> isRatingBarConstraint = ViewMatchers.isAssignableFrom(RatingBar.class);
        return isRatingBarConstraint;
    }

    @Override
    public String getDescription() {
        return "Custom view action to set rating.";
    }

    @Override
    public void perform(UiController uiController, View view) {
        RatingBar ratingBar = (RatingBar) view;
        ratingBar.setRating(3);
    }
}

Answer 2

您需要创建一个ViewAction的自定义子类，在视图上调用setRating，然后将自定义视图操作的实例传递给perform（）方法。

Answer 3

您可以将tap事件发送到视图的正确部分，而不是在以编程方式设置评级的自定义View操作中调用setRating 。

这意味着您可以在生产代码中使用boolean fromUser参数，从而无需在设置评级之前将评级栏更改侦听器设置为null：

ratingBar.setRating(viewModel.rating());
ratingBar.setOnRatingBarChangeListener(new RatingBar.OnRatingBarChangeListener() {
    @Override
    public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) {
        if (fromUser) {
            viewModel.actions().onRate(rating);
        }
    }
});

---

以下操作对我来说已经足够了，因为我的评级栏设置为0.5步并且共有5颗星：

RateableMovieViewModel viewModel = viewModel(userActions).build();
rateableMovieViewHolder.bind(viewModel);

onView(withId(R.id.item_rateable_rating)).perform(setRating(4.5f));

verify(userActions).onRate(4.5f);

---

private static ViewAction setRating(final float rating) {
    if (rating % 0.5 != 0) {
        throw new IllegalArgumentException("Rating must be multiple of 0.5f");
    }

    return new ViewAction() {
        @Override
        public Matcher<View> getConstraints() {
            return isAssignableFrom(RatingBar.class);
        }

        @Override
        public String getDescription() {
            return "Set rating on RatingBar in 0.5f increments";
        }

        @Override
        public void perform(UiController uiController, View view) {
            GeneralClickAction viewAction = new GeneralClickAction(
                    Tap.SINGLE,
                    new CoordinatesProvider() {
                        @Override
                        public float[] calculateCoordinates(View view) {
                            int[] locationOnScreen = new int[2];
                            v.getLocationOnScreen(locationOnScreen);
                            int screenX = locationOnScreen[0];
                            int screenY = locationOnScreen[1];
                            int numStars = ((RatingBar) view).getNumStars();
                            float widthPerStar = 1f * view.getWidth() / numStars;
                            float percent = rating / numStars;
                            float x = screenX + view.getWidth() * percent;
                            float y = screenY + view.getHeight() * 0.5f;
                            return new float[]{x - widthPerStar * 0.5f, y};
                        }
                    },
                    Press.FINGER,
                    InputDevice.SOURCE_UNKNOWN,
                    MotionEvent.BUTTON_PRIMARY
            );
            viewAction.perform(uiController, view);
        }
    };
}