@Override public Drawable mutate() { if (!mMutated && super.mutate() == this) { final int N = mDrawableContainerState.getChildCount(); final Drawable[] drawables = mDrawableContainerState.getChildren(); for (int i = 0; i < N; i++) { if (drawables[i] != null) drawables[i].mutate(); } mMutated = true; } return this; }