Android Espresso - Click checkbox if not checked

I also wanted to toggle a checkbox/switch depending on it's previous state. At first, I tried this to toggle ON a checkbox that was OFF:

onView(withId(R.id.checkbox)).check(matches(isNotChecked())).perform(scrollTo(), click());

...and this to toggle OFF a checkbox that was ON:

onView(withId(R.id.checkbox)).check(matches(isChecked())).perform(scrollTo(), click());

However, this doesn't work, since Espresso will be looking for a specific toggle state before it performs the action. Sometimes, you don't know whether it's ON or OFF beforehand.

My solution is to use a custom ViewAction to turn OFF/ON any checkable object (Switch, Checkbox, etc.) that isn't dependent on previous state. So, if it's already ON, it'll stay ON. If it's OFF, it'll toggle ON. Here's the ViewAction:

public static ViewAction setChecked(final boolean checked) {
    return new ViewAction() {
        @Override
        public BaseMatcher<View> getConstraints() {
            return new BaseMatcher<View>() {
                @Override
                public boolean matches(Object item) {
                    return isA(Checkable.class).matches(item);
                }

                @Override
                public void describeMismatch(Object item, Description mismatchDescription) {}

                @Override
                public void describeTo(Description description) {}
            };
        }

        @Override
        public String getDescription() {
            return null;
        }

        @Override
        public void perform(UiController uiController, View view) {
            Checkable checkableView = (Checkable) view;
            checkableView.setChecked(checked);
        }
    };
}

And here's how you use it (in this example, when you want to toggle to ON):

onView(withId(R.id.toggle)).perform(scrollTo(), setChecked(true));

Just as @FrostRocket suggested but written in Kotlin.

We define a custom action that can only performed on checkable items (as specified in constraints). So we safely cast the view to Checkable to access setCheckable method.

fun setChecked(checked: Boolean) = object : ViewAction {
    val checkableViewMatcher = object : BaseMatcher<View>() {
        override fun matches(item: Any?): Boolean = isA(Checkable::class.java).matches(item)
        override fun describeTo(description: Description?) {
            description?.appendText("is Checkable instance ")
        }
    }

    override fun getConstraints(): BaseMatcher<View> = checkableViewMatcher
    override fun getDescription(): String? = null
    override fun perform(uiController: UiController?, view: View) {
        val checkableView: Checkable = view as Checkable
        checkableView.isChecked = checked
    }
}

This seems to be part of your test, that the checkbox needs to be checked.

You can check this by:

onView(withId(R.id.checkbox)).check(matches(not(isChecked())));

If this fails, your test will fail, which may be good in your case. Then, you can perform the click you want after this case matches.

If this is not the situation you want, can you explain more on what you are trying to do in this Espresso Test?