Android Espresso - Click checkbox if not checked

Question

I have onView(withId(R.id.check_box)).perform(click()), but i only want to do this if the check box is not already checked. How can I do this in espresso?

Answer 1

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