Question

Is there a way to continuously loop through a countdown timer? I have a basic timer of going though 60 seconds, then updating a text field and it’s working, but I want to add the functionality: when it’s counted down, to automatically restart again until the user cancels it? Maybe run it through a thread? Not sure how to handle it. Here is what I have, and again, this code works, but I can only stop and start the countdown timer, not do a continuous loop:

cdt = new CountDownTimer(60000,1000) {
    public void onTick(long millisUntilFinished) { 
        tvTimer.setText("remaining : " + millisUntilFinished/1000 + " secs");
    }
     public void onFinish() { 
       tvTimer.setText("");
       bell.start(); 
     }
 };

 /***************On Click/Touch Listeners*******************/
 btnNext.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
        tvTimer.setText("");
        btnStart.setText("Start Timer");
        SetImageView2(myDbHelper); 
        cdt.cancel(); 

       }
    });

    btnStart.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
        if (!TimerTicking){ 
          cdt.start();
          btnStart.setText("Stop Timer");
        }
        else { 
            tvTimer.setText("");
            cdt.cancel();
            btnStart.setText("Start Timer");

        }
       }
    });

Answer 1

One very basic way to loop a CountDownTimer is to call start() in onFinished().

public void onFinish() {
    ...
    start();  // Start this timer over
}

(Make sure you cancel your CountDownTimer in onPause() when you do this otherwise the timer might leak and keep firing in the background… Oops.)

However CountDownTimers has fundamental flaws (in my opinion): it often skips the last call to onTick() and it gains a few milliseconds each time onTick() is called… 🙁 I re-wrote CountDownTimer in a previous question to be more accurate and call every tick.