Draw rect drawable to overlay, best for testing Camera Preview

RectDrawable.kt

class RectDrawable(rect: Rect): Drawable() {

    private val boundingRectPaint = Paint().also {
        it.style = Paint.Style.STROKE
        it.color = Color.RED
        it.strokeWidth = 4f
        it.alpha = 255
    }

    init {
        bounds = rect
    }

    override fun draw(canvas: Canvas) {
        canvas.drawRect(bounds, boundingRectPaint)
    }

    override fun setAlpha(alpha: Int) {
        boundingRectPaint.alpha = alpha
    }

    override fun setColorFilter(colorFilter: ColorFilter?) {
        boundingRectPaint.colorFilter = colorFilter
    }

    @Deprecated("Deprecated in Java")
    override fun getOpacity(): Int {
        return PixelFormat.OPAQUE
    }

    companion object {
        fun ViewGroupOverlay.reloadCodes(items: List<Rect>) {
            this.clear()
            items.forEach {
                this.add(RectDrawable(it))
            }
        }
    }
}