In Espresso, how to avoid AmbiguousViewMatcherException when multiple views match

I was amazed that I couldn't find a solution by simply providing an index along with a matcher (i.e. withText, withId). The accepted answer only solves the problem when you're dealing with onData and ListViews.

If you have more than one view on the screen with the same resId/text/contentDesc, you can choose which one you want without causing an AmbiguousViewMatcherException by using this custom matcher:

public static Matcher<View> withIndex(final Matcher<View> matcher, final int index) {
    return new TypeSafeMatcher<View>() {
        int currentIndex = 0;

        @Override
        public void describeTo(Description description) {
            description.appendText("with index: ");
            description.appendValue(index);
            matcher.describeTo(description);
        }

        @Override
        public boolean matchesSafely(View view) {
            return matcher.matches(view) && currentIndex++ == index;
        }
    };
}

For example:

onView(withIndex(withId(R.id.my_view), 2)).perform(click());

will perform a click action on the third instance of R.id.my_view.

You should use onData() to operate on GridView:

onData(withId(R.id.item_image))
        .inAdapterView(withId(R.id.grid_adapter_id))
        .atPosition(0)
        .perform(click());

This code will click on the image inside first item in GridView

Not completely related to grid view situation but you can use hamcrest allOf matchers to combine multiple conditions:

import static org.hamcrest.CoreMatchers.allOf;

onView(allOf(withId(R.id.login_password), 
             withEffectiveVisibility(ViewMatchers.Visibility.VISIBLE)))
        .check(matches(isCompletelyDisplayed()))
        .check(matches(withHint(R.string.password_placeholder)));