Cannot format given Object as a Number in Kotlin - kotlin

Question

An error occurred while using the ConverPrice function as follows for information about the price.
The price of the item in the recycler view adapter onBindViewHolder.
As a result of debugging, the error occurs in the following code.
priceText =
"${dec.format(priceMin)} ~ ${dec.format(priceMax)}"
Please check my code and answer.
override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
when (holder) {
is DataViewHolder -> {
val item = dataList[position]
item.price.let {
holder.price.text = ConvertPrice(item, holder.price)
}
}
}
}
fun ConvertPrice(productDetail: ProductDetail?, tv: TextView? = null, setPrice: Boolean = false): String {
val disableColor = Color.parseColor("#aaaaaa")
val enableColor = Color.parseColor("#3692ff")
tv?.setTextColor(disableColor)
if (ProductDetail != null) {
val priceMin = productDetail.priceMin
val priceMax = productDetail.priceMax
var priceText = ""
val dec = DecimalFormat("##,###")
productDetail.enabledRetail?.let {
if (productDetail.enabledRetail == true) {
if (setPrice) {
priceText = if (priceMin == null || priceMax == null) {
"No pricing information"
} else {
"${dec.format(priceMin)} ~ ${dec.format(priceMax)}"
}
tv?.setTextColor(disableColor)
}
else {
priceText = dec.format(wineDetail.price).toString()
tv?.setTextColor(enableColor)
}
return priceText
} else if (productDetail.cntRating!! > 0) {
if ((priceMin == null && priceMax == null) || (priceMin == 0 && priceMax == 0)) {
priceText = "No pricing information"
} else {
priceText =
"${dec.format(priceMin)} ~ ${dec.format(priceMax)}"
tv?.setTextColor(disableColor)
}
return priceText
}
}
}
return "No pricing information"
}

Answer 1

DecimalFormat.format() only works fine with long or double. You should convert "priceMin" and "priceMax" to Long.
val priceMin = productDetail.priceMin.toLong()
val priceMax = productDetail.priceMax.toLong()
I recommend to use NumberFormat instead of DecimalFormat because it is locale-sensitive
val decFormat = NumberFormat.getInstance() // or getCurrencyInstance()
decFormat.maximumFractionDigits = 3
decFormat.format(priceMin)
decFormat.format(priceMax)