Espresso - Check RecyclerView items are ordered correctly

Question

How to go about checking whether RecyclerView items are displayed in the correct order using Espresso? I\'m trying to test it checking it by the text for the title of each e

Answer 1

As it's been mentioned here, RecyclerView objects work differently than AdapterView objects, so onData() cannot be used to interact with them.

In order to find a view at specific position of a RecyclerView you need to implement a custom RecyclerViewMatcher like below:

public class RecyclerViewMatcher {
    private final int recyclerViewId;

    public RecyclerViewMatcher(int recyclerViewId) {
        this.recyclerViewId = recyclerViewId;
    }

    public Matcher atPosition(final int position) {
        return atPositionOnView(position, -1);
    }

    public Matcher atPositionOnView(final int position, final int targetViewId) {

        return new TypeSafeMatcher() {
            Resources resources = null;
            View childView;

            public void describeTo(Description description) {
                String idDescription = Integer.toString(recyclerViewId);
                if (this.resources != null) {
                    try {
                        idDescription = this.resources.getResourceName(recyclerViewId);
                    } catch (Resources.NotFoundException var4) {
                        idDescription = String.format("%s (resource name not found)",
                                                      new Object[] { Integer.valueOf
                                                          (recyclerViewId) });
                    }
                }

                description.appendText("with id: " + idDescription);
            }

            public boolean matchesSafely(View view) {

                this.resources = view.getResources();

                if (childView == null) {
                    RecyclerView recyclerView =
                        (RecyclerView) view.getRootView().findViewById(recyclerViewId);
                    if (recyclerView != null && recyclerView.getId() == recyclerViewId) {
                        childView = recyclerView.findViewHolderForAdapterPosition(position).itemView;
                    }
                    else {
                        return false;
                    }
                }

                if (targetViewId == -1) {
                    return view == childView;
                } else {
                    View targetView = childView.findViewById(targetViewId);
                    return view == targetView;
                }

            }
        };
    }
}

And then use it in your test case in this way:

@Test
void testCase() {
    onView(new RecyclerViewMatcher(R.id.rv_metrics)
        .atPositionOnView(0, R.id.txt_title))
        .check(matches(withText("Weight")))
        .perform(click());

    onView(new RecyclerViewMatcher(R.id.rv_metrics)
        .atPositionOnView(1, R.id.txt_title))
        .check(matches(withText("Height")))
        .perform(click());
}