How to use a variable in an AsyncTask before it is modified?

Issue

I want to use a parameter of my class in an AsyncTask, but this parameter changes just after the AsyncTask. So when the AsyncTask is executed, this variable has already changed and I have the new value of the parameter instead of the old one.

I tried to use the AsyncTask.execute {}, to create a class extending AsyncTask, but nothing to do.

data class Case(var id: Long, var nom: String, var nomCourt: String, var couleur: String, var couleurTexte: String, var prix: Double, var nombre: Int = 0)

class Moteur(): Parcelable {
    //I didn't past the code of the Parcelable, because it doesn't matter to this problem.
    var cases : List<Case> = listOf(
        Case(0, "Bouchon 1", "B1", "#008000", "#FFFFFF", 5.0),
        Case(1, "Bouchon 2", "B2", "#800000", "#000000", 1.5),
        Case(2, "Bouchon 3", "B3", "#000080", "#FFFFFF", 3.0),
        Case(3, "Bouchon 4", "B4", "#808000", "#000000", 7.0),
        Case(4, "Bouchon 5 qui est long et cher", "B5",  "#008080", "#FFFFFF", 15.0)
    )
    enregistrerCommande() {
        //Of course, the property nombre of the Cases have changed before this function is called, but here is not the problem. In the Log, I have the good values and next the wrong one.
        Log.i("REGCOM", "avant : $cases")
        AsyncTask.execute {
            val bdd = Room.databaseBuilder(context!!, MaBdd::class.java, "historique").build()
            val dao = bdd.historiqueDao()
            Log.i("REGCOM", "après : ${cases[0]}")
            for (i in cases) dao.insertAll(Historique(0L, i!!.nombre, false))
            idProchainAchat ++
            context!!.getSharedPreferences("all", Context.MODE_PRIVATE).edit().putLong("idProchainAchat", idProchainAchat).apply()
            bdd.close()
        }
        cases.forEach{it.nombre = 0}
        prixCommande = 0.0
    }
}

It should register the values of the properties nombre in my db Historique, but it allways register five times 0.

Thank you for your help !

PS Sorry for my bad english, I speak french.

Solution

I've juste have found a solution, maybe not the best, but it works.

fun enregistrerCommande() {
    val temp = mutableMapOf<Long, Int>()
    cases.forEach { temp[it.id] = it.nombre }

    doAsync {
        val bdd = Room.databaseBuilder(context!!, MaBdd::class.java, "historique").build()
        val dao = bdd.historiqueDao()
        for ((clef, valeur) in temp) dao.insertAll(Historique(0L, clef, valeur, false))
        idProchainAchat ++
        context!!.getSharedPreferences("all", Context.MODE_PRIVATE).edit().putLong("idProchainAchat", idProchainAchat).apply()
        bdd.close()
    }
    cases.forEach{it.nombre = 0}
    prixCommande = 0.0

}

The solution is to "save" the datas in a Map (I used the map because I just needed the two values, but a List would be good as long as you use this method, which is not working with pointer (I think that when you write val temp = cases you make an other list, but with the same pointers on the objects Case. I think it because of my precedents trials.)). I used the doAsync function of anko to reduce the quantity of code, but the AsyncTask.execute{} works as well.

I hope some one will be able to use my answer in spite of my bad english.

Answered By - niaou suzanne