Custom GradientDrawable doesn't work on Android Lollipop

Question

I want to use RingDrawable in my android application (no xml).

I found this code RingDrawable.java, but it doesn't work on Android Lollipop. There is simply no effect at all. Could you tell me please how to improve this? Thank you!

public class RingDrawable extends GradientDrawable {

    private Class<?> mGradientState;

    public RingDrawable() {
        this(Orientation.TOP_BOTTOM, null);
    }

    public RingDrawable(int innerRadius, int thickness, float innerRadiusRatio, float thicknessRatio) {
        this(Orientation.TOP_BOTTOM, null, innerRadius, thickness, innerRadiusRatio, thicknessRatio);
    }

    public RingDrawable(GradientDrawable.Orientation orientation, int[] colors) {
        super(orientation, colors);
        setShape(RING);
    }

    public RingDrawable(GradientDrawable.Orientation orientation, int[] colors, int innerRadius, int thickness, float innerRadiusRatio, float thicknessRatio) {
        this(orientation, colors);
        try {
            setInnerRadius(innerRadius);
            setThickness(thickness);
            setInnerRadiusRatio(innerRadiusRatio);
            setThicknessRatio(thicknessRatio);
        } catch (Exception e) {
            // fail silently - change to your own liking
            e.printStackTrace();
        }
    }

    public void setInnerRadius(int radius) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
        if (mGradientState == null) mGradientState = resolveGradientState();
        Field innerRadius = resolveField(mGradientState, "mInnerRadius");
        innerRadius.setInt(getConstantState(), radius);
    }       

    public void setThickness(int thicknessValue) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
        if (mGradientState == null) mGradientState = resolveGradientState();
        Field thickness = resolveField(mGradientState, "mThickness");
        thickness.setInt(getConstantState(), thicknessValue);
    }

    public void setInnerRadiusRatio(float ratio) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
        if (mGradientState == null) mGradientState = resolveGradientState();
        Field innerRadiusRatio = resolveField(mGradientState, "mInnerRadiusRatio");
        innerRadiusRatio.setFloat(getConstantState(), ratio);
    }

    public void setThicknessRatio(float ratio) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
        if (mGradientState == null) mGradientState = resolveGradientState();
        Field thicknessRatio = resolveField(mGradientState, "mThicknessRatio");
        thicknessRatio.setFloat(getConstantState(), ratio);
    }

    private Class<?> resolveGradientState() {
        Class<?>[] classes = GradientDrawable.class.getDeclaredClasses();
        for (Class<?> singleClass : classes) {
            if (singleClass.getSimpleName().equals("GradientState")) return singleClass;
        }
        throw new RuntimeException("GradientState could not be found in current GradientDrawable implementation");
    }

    private Field resolveField(Class<?> source, String fieldName) throws SecurityException, NoSuchFieldException {
        Field field = source.getDeclaredField(fieldName);
        field.setAccessible(true);
        return field;
    }

}