Memory Leak in Custom Alert dialog animation Android

Question

I'm using an alert dialog to show an animation (green tick mark on success api call). But it's causing a memory leak if I press the home button before the animation ends.

To reproduce, I enabled "Finish Activities" in Developer Options.

Attaching the code below for "Tick Animation" and the custom dialog box which shows that animation.

SuccessAnimation.kt

class SuccessAnimation @JvmOverloads constructor(
    context: Context, attrs: AttributeSet? = null,
) : RelativeLayout(context, attrs) {
    private val circleFadeInTime: Long
    private val checkAnimationTime: Long
    val postAnimationTime: Long

    init {
        inflate(context, R.layout.success_content, this)
        val a = context.obtainStyledAttributes(attrs, R.styleable.SuccessAnimation, 0, 0)
        try {
            circleFadeInTime = a.getInteger(R.styleable.SuccessAnimation_circleAppearanceTime, DEFAULT_CIRCLE_TIME).toLong()
            checkAnimationTime = a.getInteger(R.styleable.SuccessAnimation_checkMarkAnimationTime, DEFAULT_ANIMATION_TIME).toLong()
            postAnimationTime = a.getInteger(R.styleable.SuccessAnimation_postAnimationTime, DEFAULT_POST_ANIMATION_TIME).toLong()
        } finally {
            a.recycle()
        }
        isClickable = true // Prevent anything else from happening!

    }

    val animationDuration = circleFadeInTime + checkAnimationTime + postAnimationTime
    private val circle: View = findViewById(R.id.green_circle)
    private val checkMark = findViewById<AnimatedCheckMark>(R.id.check_mark).apply { setAnimationTime(checkAnimationTime) }


    private var onAnimationFinished: (() -> Unit)? = {}

    /**
     * Set a callback to be invoked when the animation finishes
     * @param listener listener to be called
     */
    fun setSuccessFinishedListener(listener: (() -> Unit)?) {
        this.onAnimationFinished = listener
    }

    /**
     * start the animation, also handles making sure the view is visible.
     */
    fun show() {
        if (visibility != VISIBLE) {
            visibility = VISIBLE
            post { show() }
            return
        }
        circle.visibility = VISIBLE
        circle.scaleX = 0f
        circle.scaleY = 0f
        val animator = ValueAnimator.ofFloat(0f, 1f)
        animator.addUpdateListener { animation: ValueAnimator ->
            val scale = animation.animatedFraction
            circle.scaleY = scale
            circle.scaleX = scale
            circle.invalidate()
        }
        animator.duration = circleFadeInTime
        animator.interpolator = OvershootInterpolator()
        animator.addListener(object : AnimatorListenerAdapter() {
            override fun onAnimationEnd(animation: Animator) {
                checkMark!!.visibility = VISIBLE
                invalidate()
                checkMark.startAnimation { view: AnimatedCheckMark ->
                    view.postDelayed({
                        visibility = GONE
                        checkMark.visibility = INVISIBLE
                        circle.visibility = INVISIBLE
                        onAnimationFinished?.invoke()
                    }, postAnimationTime)
                }
            }
        })
        invalidate()
        animator.start()
    }
    companion object{
        private const val DEFAULT_CIRCLE_TIME = 300
        private const val DEFAULT_ANIMATION_TIME = 500
        private const val DEFAULT_POST_ANIMATION_TIME = 500

    }
}

SuccessAnimationPopup.kt

class SuccessAnimationPopup(context: Context,
                            private val callback: () -> Unit) :
    AlertDialog(context, android.R.style.Theme_Translucent_NoTitleBar) {
    init {
        window?.let {
            it.setFlags(
                WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION,
                WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION
            )
            it.setFlags(
                WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS,
                WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS
            )
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.success_animation_popup)
        setCancelable(false)

        val success = findViewById<SuccessAnimation>(R.id.success_animation)
        success?.setSuccessFinishedListener {
            dismiss()
            callback()
        }
        success?.show()
    }
}

It is being used like the following:

SuccessAnimationPopup(view.context) {}.show() I only have "view" here and not the activity.

Been trying to find the root cause. Have also added onDetachedFromWindow lifecycle callback in SuccessAnimation.kt and tried setting the onAnimationListener = null, still doesn't work.

What am I missing here?

Also, the AlertDialog constructor is not accepting a nullable context, hence I wasn't able to pass a WeakReference since it's nullable.