How to create a countdown stopwatch in java

Question

When I call the function() I want to have a chance to cancel the SOS call, If I click the button. Basically It reads Integer.parseInt(cancelTime.getText().toString()) that has a time in second to be able to cancel.

My problem is that I'm trying to show like a countdown of the time elapsed from Integer.parseInt(cancelTime.getText().toString()) to 0 and it appears a huge number: ex: 10546468261

private void function()
{    

    startTime = System.currentTimeMillis();

    Runnable runnable = new Runnable() {
        @Override
        public void run() {
            double elapsedTime = (System.currentTimeMillis() - startTime)/1000;
            alertButton.setText("CANCEL THE SOS: " + (int)elapsedTime);
            alertButton.setBackgroundColor(Color.parseColor("#FF0000"));
        }
    };

    Handler handler = new Handler();
    handler.postDelayed(runnable, Integer.parseInt(cancelTime.getText().toString()));
}

What do you mean? I only want to show like 3 seconds instead of 3.02139012931239120391 — , Jun 23 '17 at 08:30
try formating/rounding it here is the link with a similar problem https://stackoverflow.com/questions/153724/how-to-round-a-number-to-n-decimal-places-in-java — LazerBanana, Jun 23 '17 at 08:31
You seem to be calling the runnable *after* the delay has run out? — Steve Smith, Jun 23 '17 at 08:33

score 0 · Answer 1 · answered Jun 23 '17 at 12:08

I have modified your code, This may help you.

private void function()
{    

     new CountDownTimer(30000, 1000) {

     public void onTick(long millisUntilFinished) {
     alertButton.setText("seconds remaining: " + millisUntilFinished / 1000);
     alertButton.setBackgroundColor(Color.parseColor("#FF0000"));
     }

     public void onFinish() {
         alertButton.setText("Cancel SOS");
     }
  }.start();
}

Modify new CountDownTimer(30000, 1000) as per your need

Parameter 1:- long millisInFuture

Parameter 2:- long countDownInterval

How to create a countdown stopwatch in java

1 Answers1