Updating TextView with clock

Question

I have been trying to create a program that will output a working digital clock that will allow me to quickly access the date and time. I have the code to parse the time, however, I'm having difficulty updating the textview. I have this:

    `public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    timer = (TextView)findViewById(R.id.timer);

    time = new Time();
    time.setToNow();

    timeString = time.toString();
    changeTime = Parser(timeString);


    time.setToNow();
    timeString = time.toString();
    changeTime = Parser(timeString);

    timer.setText(changeTime);  
    } 
    private String Parser(String time){

    String year = time.substring(0, 4);
    String month = time.substring(4,6);
    String day = time.substring(6, 8);
    String hour = time.substring(9,11);
    String minute = time.substring(11, 13);
    String second = time.substring(13, 15);

    String finalTime = hour + ":" + minute + ":" + second + " " + day + " " + month + " "  + year;
    //String finalTime = second;
    return finalTime;


}`

How do I put this in a loop to constantly update the textview.

Thanks for any help you can give me.

Answer 1

Declare a Handler to update the TextView on the UI thread.

private Handler mHandler = new Handler() {
 @Override
 public void handleMessage(Message msg) {
    time = new Time();
    time.setToNow();

    timeString = time.toString();
    changeTime = Parser(timeString); 
    timer.setText(changeTime);  
 }
};

Start a TimeTask that will update your TextView

int initialDelay = 1000; //first update in miliseconds
int period = 5000;      //nexts updates in miliseconds       

Timer timer = new Timer();
TimerTask task = new TimerTask() {
  public void run() {
      Message msg = new Message();
      mHandler.sendMessage(msg);
  }
};
timer.scheduleAtFixedRate(task, initialDelay, period);