AsyncTask in Android with Kotlin

Question

How to make an API call in Android with Kotlin?

I have heard of Anko . But I want to use methods provided by Kotlin like in Android we have Asynctask for background

Answer 1

I spent a full day trying to figure how to get back the result produced by an Async Task : co-routines was my solution !!!

First, create your AsyncTask Object ... Do not forget to use corrects parameter type instead all Any

@SuppressLint("StaticFieldLeak")
class AsyncTaskExample(private var activity: MainActivity?) : AsyncTask() {

    override fun onPreExecute() {
        super.onPreExecute()
        // do pre stuff such show progress bar
    }

    override fun doInBackground(vararg req: Any?): Any? {

        // here comes your code that will produce the desired result
        return result 

    }

    // it will update your progressbar
    override fun onProgressUpdate(vararg values: Int?) {
        super.onProgressUpdate(*values)

    }


    override fun onPostExecute(result: Any?) {
        super.onPostExecute(result)

        // do what needed on pos execute, like to hide progress bar
        return
    }

}

and Then, call it ( in this case, from main activity )

var task = AsyncTaskExample(this)
var req = { "some data object or whatever" }

GlobalScope.launch( context = Dispatchers.Main){

   task?.execute(req)
}

GlobalScope.launch( context = Dispatchers.Main){

   println( "Thats the result produced by doInBackgorund: " +  task?.get().toString() )
}