ConstraintLayout with an option to grey out the entire content (disabled like)

ConstraintLayoutWithDisableSupport.kt

package com.example.grayscaleexperiment

import android.content.Context
import android.graphics.Canvas
import android.graphics.ColorMatrix
import android.graphics.ColorMatrixColorFilter
import android.graphics.Paint
import android.util.AttributeSet
import androidx.constraintlayout.widget.ConstraintLayout

//origin: https://github.com/iabhishek1041/grayscale_experiment/blob/master/app/src/main/java/com/example/grayscaleexperiment/ConstraintLayoutWithDisableSupport.kt

class ConstraintLayoutWithDisableSupport @JvmOverloads constructor(
    context: Context,
    attrs: AttributeSet? = null,
    defStyleAttr: Int = 0
) : ConstraintLayout(context, attrs, defStyleAttr) {

    var disabled = false
        set(value) {
            field = value
            requestLayout()
        }

    private val paint = Paint()

    init {
        val cm = ColorMatrix()
        cm.set(
            floatArrayOf(
                0.33f, 0.33f, 0.33f, 0f, 0f,
                0.33f, 0.33f, 0.33f, 0f, 0f,
                0.33f, 0.33f, 0.33f, 0f, 0f,
                0f, 0f, 0f, 1f, 0f
            )
        )
        paint.colorFilter = ColorMatrixColorFilter(cm)
    }

    override fun dispatchDraw(canvas: Canvas?) {
        if (disabled) {
            canvas?.saveLayer(null, paint)
        }

        super.dispatchDraw(canvas)

        if (disabled) {
            canvas?.restore()
        }
    }

    override fun draw(canvas: Canvas?) {
        if (disabled) {
            canvas?.saveLayer(null, paint)
        }

        super.draw(canvas)

        if (disabled) {
            canvas?.restore()
        }
    }
}