我的RecyclerView包含各种类型的项目。其中一种类型具有TextView标题和用于显示列表的RecyclerView。单击标题将填充/取消填充RecyclerView，从而对其进行扩展/折叠。
我想我注意到一个展开/折叠动画，但是它非常快。问题是如何放慢速度使其更引人注意？
代码：
...
itemView.showIncludedCountriesTextAndArrowLayout.setOnClickListener {
val whatCountriesAreIncludedLayout: ConstraintLayout = itemView.findViewById(R.id.whatCountriesAreIncludedLayout)
if (countryGridAdapter?.itemCount == 0) {
itemView.upOrDownArrowImageView.setImageResource(R.drawable.ic_up_arrow_32dp)
itemView.showTheIncludedCountriesTextView.text = mobileSubscriptionSiteCoreSectionData.countriesListCollapseText
countryGridAdapter.updateList(mobileSubscriptionSiteCoreSectionData.countryList)
// Bottom margin.
val layoutParams = whatCountriesAreIncludedLayout.layoutParams as RecyclerView.LayoutParams
layoutParams.bottomMargin = context.resources.getDimensionPixelSize(R.dimen.countriesIncludedVisibleList)
whatCountriesAreIncludedLayout.layoutParams = layoutParams
recyclerView.requestLayout()
recyclerView.invalidate()
onShowHideListViewClickListener.onClick(it, true, viewHolder.adapterPosition,
(itemView.showIncludedCountriesTextAndArrowLayout.top +
itemView.showIncludedCountriesTextAndArrowLayout.paddingTop +
itemView.showIncludedCountriesTextAndArrowLayout.paddingBottom) * -1)
} else {
itemView.upOrDownArrowImageView.setImageResource(R.drawable.ic_down_arrow_32dp)
itemView.showTheIncludedCountriesTextView.text = mobileSubscriptionSiteCoreSectionData.countriesListExpandText
countryGridAdapter?.updateList(listOf())
// Bottom margin.
val layoutParams = whatCountriesAreIncludedLayout.layoutParams as RecyclerView.LayoutParams
layoutParams.bottomMargin = 0
whatCountriesAreIncludedLayout.layoutParams = layoutParams
recyclerView.requestLayout()
recyclerView.invalidate()
onShowHideListViewClickListener.onClick(it, false)
}
}
...