java - How to end tasks which works in background

Question

Hello I am making boxing countdown timer and I have the ring that plays at the end and start of each round. I would like to make "end" button but when I am using Intent like bellow I go to previously activity but mp3 files still working in background. How to end all tasks and go to previously activity without any mp3 and tasks in background?

 btn1.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
            AlertDialog.Builder  dialog=new AlertDialog.Builder(Main3Activity.this);
            dialog.setMessage("Czy napewno chcesz wyj?? z trenignu?");
            dialog.setPositiveButton("Tak", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                    Intent intent=new Intent(Main3Activity.this, Main5Activity.class);
                    startActivity(intent);



                }
            });

            dialog.setNegativeButton("Nie", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                }
            });
            AlertDialog dialogg=dialog.create();
            dialogg.show();
        }
    });`
           

question from:https://stackoverflow.com/questions/65882740/how-to-end-tasks-which-works-in-background

Answer 1

removeEventListener()

use HTML DOM removeEventListener() Method

btn1.removeEventListener("click", function(){});

see: https://www.w3schools.com/JSREF/met_element_removeeventlistener.asp