Animation Extension Functions

animations.kt

fun View.slideDownToShow(startPosition: Float, duration: Long = 300L){

    if (this.visibility == View.GONE || this.visibility == View.INVISIBLE){
        this.visibility = View.VISIBLE
    }

    val translationAnimation = TranslateAnimation(
            0f, // fromXDelta
            0f, // toXDelta
            - startPosition, // fromYDelta
            0f // toYDelta
    )
    val alphaAnimation = AlphaAnimation(
            0f, // fromAlpha
            1f // toAlpha
    )

    translationAnimation.duration = duration
    translationAnimation.fillAfter = true

    alphaAnimation.duration = duration

    this.startAnimation(alphaAnimation)
    this.startAnimation(translationAnimation)
    
}