IssueTracker

I'm using appcompat v7 and i had some strange issue with selectableItemBackground on Android 4.2 (api 17 mr1).
In the end i have found that the strange behaviour is caused by the mutate issue of Transition/LayerDrawable that has been fixed on api level 18.
This is the code that i'm using to solve the problem:

private static Drawable getDrawableCompat(Resources res, int id) {
        Drawable d = ResourcesCompat.getDrawable(res, id, null);
        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN_MR1) {
                // fix for "TransitionDrawable should not become a LayerDrawable"
                // https://github.com/android/platform_frameworks_base/commit/90e10cc58690678937575b54e1b20b899445d0e4
                // issue fixed on api 18+ (mr2) and that happens only on api 17 (mr1) because of the different
                // drawable constantstate/mutate handling added on api 17
                // "The drawables cache strikes again"
                // https://github.com/android/platform_frameworks_base/commit/5f49c3023a512efbef8bc9515d310c7a72be4af2
                if (hasLayerDrawable(d)) {
                        d = d.getConstantState().newDrawable();
                }
        }
        return d;
}

public static boolean hasLayerDrawable(Drawable d) {
        if (d instanceof LayerDrawable) {
                return true;
        } else if (d instanceof DrawableContainer) {
                final DrawableContainer.DrawableContainerState cs = (DrawableContainer.DrawableContainerState)d.getConstantState();
                final Drawable[] children = cs.getChildren();
                if (children != null) {
                        for (Drawable child : cs.getChildren()) {
                                if (child != null) {
                                        if (hasLayerDrawable(child)) return true;
                                }
                        }
                }
        }
        return false;
}