AsyncTask is deprecated? What method used instead of onPreExecute and onPostExecute?

Question

In my old project, I used AsyncTask, but its deprecated so what method i used instead of this? If we used thread, in AsyncTask having onbackground, onPreExecute and onPostExecute Override methods where this sections called in thread. Is there any alternative method. Can you please give me the solution?

Java code:

      public class getDetailsfromWeb extends AsyncTask<Void, Void, String> {

      @Override
      protected String doInBackground(Void... params) {

        if (paymentSync == null)

            paymentSync = new ReceivePaymentSync(getActivity());

        allCreditCardModel = new AllCreditCardModel();

        allCreditCardModel = paymentSync.getGetCreditCardById(CrediCardId);

        handler.post(allCreditRunnable);

        return null;
    }

    /**
     * @param string
     */
    public void execute(String string) {

        // TODO Auto-generated method stub
    }

    protected void onPreExecute() {

        showProgress();

    }

    @Override
    protected void onPostExecute(String result) {

        progress.dismiss();

    }
}

Digest

I've answered similar question few days ago https://mcmap.net/q/1769645/-how-to-run-a-algorithm-on-a-separate-thread-while-updating-a-progressbar – Snafu

@Snafu In "long running operation " we paste doInBackground code and "Update ui on the main thread" paste onPreExecute right? – Digest

then where we paste onPostExecute code? – Digest

Depends, maybe in your case pre execute goes on the mainthread, then open the rmthread as shown in the answer, execute your heavy code in background and after put the code for posting on the mainthread from within the background thread. Actually you can post on the mainthread as many time as you want. – Snafu

use RXJava or coroutine in kotlin. – Connie

There is no simple answer to your question. You should use rxJava or kotlin coroutines together with a right architecture approach like clean architecture – Adriatic

Answer 1

This is a simple example, anyway I would give a look to the WorkManager library too:

Executors.newSingleThreadExecutor().execute(() -> {

    Handler mainHandler = new Handler(Looper.getMainLooper());

      //sync calculations

    mainHandler.post(() -> {
      //Update UI
    });

    //other sync calcs.

    mainHandler.post(() -> {
      //Update UI
    });

  });   

Snafu

I have one class which have AsyncTask like this - new AsyncTask<Integer, Void, Float>() {...} means directly, it's not like i'm calling it from somewhere, so what about params from doInBackground?? – Python

Here's link for more help - github.com/sharish/ScratchView/blob/master/views/src/main/java/… – Python

Answer 2

Just use a Thread.

The onPreExecute code goes in the constructor.

The doInBackground code goes in the run().

The onPostExecute code goes in the run of a runnable for runOnUiThread which you call at the end of the run().

Snowfield

thank you for your response. Can't understand. can u post any sample code or modify my above code?its helpful to us @Snowfield – Digest

If you google for a Thread example and then for runOnUiThread you will find all you need. There is not much in it. Then post the code you tried if it does not work and we will talk about it. Today or tomorrow ;-) – Snowfield

So the code in the constructor won't crash if i do some ui work like in post execute? i cant use runOnUiThread inside the constructor, since i also have to call that in the run() – Headspring

Yes. No need to use runOnUiThread() in the constuctor of your Thread. – Snowfield

Just sad. they should have provided an easy alternative. async task is fairly convenient. it even has status and cancel – Headspring