numberPicker.onSelectedPositionChanged = { position ->
    textView.text = "Position: $position"
}

numberPicker.itemFormatter = { index, item ->
    item.apply {
        val color = if (index == numberPicker.selectedPosition) {
            Color.RED
        } else {
            Color.BLACK
        }

        styleChanged(
            style.modifyCustomStyle<TextStyle> {
                this.copy(
                    textColor = color
                )
            }
        )
    }
}

numberPicker.onSelectedPositionChanged = { index, item ->
    
    item.apply {
        styleChanged(
            numberPicker.style.modifyCustomStyle<TextStyle> {
                this.copy(
                    textColor = when (index % 3) {
                        0 -> Color.RED
                        1 -> Color.GREEN
                        else -> Color.BLUE
                    }
                )
            }
        )
    }
}

class DrawablePickerItem(val drawable: Drawable) : PickerItem {
    private var _style: GoodPickerStyle = GoodPickerStyle.default
    override val style: GoodPickerStyle
        get() = _style
    private val _drawableStyle: DrawableStyle
        get() {
            return _style.getCustomStyle() ?: throw IllegalStateException("No drawable style found")
        }

    override fun draw(canvas: Canvas, y: Float, width: Int, height: Int) {
        val style = _drawableStyle
        canvas.save()
        canvas.translate(
            (width - style.size) / 2f, //here we center drawable
            y + ((height - style.size) / 2f),
        )
        drawable.setTint(style.tint) //before drawing we apply style
        drawable.setBounds(0, 0, style.size, style.size)
        drawable.draw(canvas)
        canvas.restore()
    }

    override fun styleChanged(style: GoodPickerStyle) {
        _style = style //after assignment you might want to invalidate your field to update paint or other things
    }

    companion object {
        fun fromResource(context: Context, resId: Int): DrawablePickerItem {
            return DrawablePickerItem(
                ContextCompat.getDrawable(context, resId)!!
            )
        }
    }
}

class DrawablePickerOverlay(
    private val _topDrawable: Drawable,
    private val _bottomDrawable: Drawable
) : PickerOverlay {
    private var _style: GoodPickerStyle = GoodPickerStyle.default
    override fun styleChanged(style: GoodPickerStyle) {
        _style = style
    }

    override fun draw(canvas: Canvas, centerItemRect: Rect) {
        _topDrawable.setBounds(
            0,
            0,
            canvas.width,
            centerItemRect.top
        )
        _topDrawable.draw(canvas)
        _bottomDrawable.setBounds(
            0,
            centerItemRect.bottom,
            canvas.width,
            canvas.height
        )
        _bottomDrawable.draw(canvas)
    }

    companion object {
        fun symmetric(topDrawable: Drawable): DrawablePickerOverlay {
            return DrawablePickerOverlay(topDrawable, RotateDrawable().apply {
                drawable = topDrawable.constantState?.newDrawable()!!.mutate()
                this.fromDegrees = 180f
            })
        }
    }
}