How to draw a smooth/dithered gradient on a canvas in Android

Seeing as you have a Canvas to work with. Here is one option.

private Bitmap makeRadGrad() {
    RadialGradient gradient = new RadialGradient(200, 200, 200, 0xFFFFFFFF,
            0xFF000000, android.graphics.Shader.TileMode.CLAMP);
    Paint p = new Paint();
    p.setDither(true);
    p.setShader(gradient);

    Bitmap bitmap = Bitmap.createBitmap(400, 400, Config.ARGB_8888);
    Canvas c = new Canvas(bitmap);
    c.drawCircle(200, 200, 200, p);

    return bitmap;
}

Result: