Drawing text with gradient

RainbowText.kt

    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
        val height = measuredHeight.toFloat()
        val width = measuredWidth.toFloat()
        val shader = LinearGradient(
                0f, 0f, width, height,
                intArrayOf(Color.RED, Color.BLUE, Color.GREEN),
                null,
                Shader.TileMode.CLAMP
        )
        paint.shader = shader
    }