White MaterialShapeDrawable is Gray upon elevation

Question

I currently have FrameLayout with the following code upon initialization in its init function

            val bgDrawable = MaterialShapeDrawable.createWithElevationOverlay(context).apply {
                fillColor = ColorStateList.valueOf(Color.WHITE)
            }
            ViewCompat.setBackground(this, bgDrawable)

When the elevation is 0, the background renders correctly white

However, when I set the elevation to greater than 0, the background becomes gray.

Somethings that I tried was setting the tint to white, but, that seems to get rid of the elevation shadow of the MaterialShapeDrawable

Goal: I just want a White MaterialShapeDrawable background value on a FrameLayout and when elevation is > 0, to stay white with the elevation shadow intact

Answer 1

It depends by the elevation overlay color and it happens only if the current theme's attribute elevationOverlayEnabled is true and the backgroundColor (fillColor) matches the theme's surface color (colorSurface attribute).

If you want to avoid this behavior you can set in your app theme:

<item name="elevationOverlayEnabled">false</item>

Check in particolar way the app theme in the dark mode where this attribute is true by default.