I have been trying to figure out how to make a custom chronometer that

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Asked: May 31, 20262026-05-31T13:16:59+00:00 2026-05-31T13:16:59+00:00

I have been trying to figure out how to make a custom chronometer that

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I have been trying to figure out how to make a custom chronometer that is precise down to a hundredth of a second. I have looked at a lot of the other similar questions and decided to try it using a thread and handler.

This is my custom handleMessage method:

public void handleMessage(Message msg) {
    String timeText = msg.getData().getString("time");
    watch.setText(timeText);
}

The watch object is just a TextView that is initialized in onCreate().

And this is the main chunk of my run method:

while(true) {
    long timeElapsed = System.currentTimeMillis() - startTime;
    int hundreths = (int)((timeElapsed % 1000) / 10);
    int seconds = (int)((timeElapsed % 60000) / 1000);
    int minutes = (int)(timeElapsed / 60000);
    Bundle bundle = new Bundle();
    bundle.putString("time", String.format("d:%02d.%02d", minutes, seconds, hundreths));
    Message msg = handler.obtainMessage();
    msg.setData(bundle);
    handler.handleMessage(msg);
}

I realize that the whole idea behind using a handler is that only the UI thread can update elements on the screen, but I am still getting a CalledFromWrongThreadException with the message that only the original thread that started created the View hierarchy can call methods on it. I am confused as to what exactly I am doing wrong.