Real World Example

Example

enum class OrderStatus(val label: String, val progress: Int) {
    PLACED("Order placed", 10),
    ACCEPTED("Restaurant accepted", 30),
    PREPARING("Food is being prepared", 55),
    OUT_FOR_DELIVERY("On the way", 80),
    DELIVERED("Delivered", 100),
    CANCELLED("Cancelled", 0);

    val isActive get() = this != DELIVERED && this != CANCELLED

    fun next(): OrderStatus = when (this) {
        PLACED -> ACCEPTED
        ACCEPTED -> PREPARING
        PREPARING -> OUT_FOR_DELIVERY
        OUT_FOR_DELIVERY -> DELIVERED
        DELIVERED, CANCELLED -> this
    }
}

fun progressBar(p: Int) = "[" + "#".repeat(p / 10) + "-".repeat(10 - p / 10) + "]"

fun main() {
    var status = OrderStatus.PLACED
    while (status.isActive) {
        println("${progressBar(status.progress)} ${status.label}")
        status = status.next()
    }
    println("${progressBar(status.progress)} ${status.label}")
}

Output

[#---------] Order placed
[###-------] Restaurant accepted
[#####-----] Food is being prepared
[########--] On the way
[##########] Delivered