gistfile1.java

package com.johnlindquist;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.widget.TextView;

import java.math.BigInteger;
import java.security.SecureRandom;
import java.util.Timer;
import java.util.TimerTask;

public class HelloAndroid extends Activity
{
    private Handler handler;
    private TextView viewById;

    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        viewById = (TextView) findViewById(R.id.textView1);
        viewById.setText("Hello, Android World");

        handler = new Handler();
        UpdateText updateText = new UpdateText();
        handler.postDelayed(updateText, 1000);
    }

    private class UpdateText extends TimerTask
    {
        @Override
        public void run()
        {
            String random = new BigInteger(130, new SecureRandom()).toString(32); //random string
            viewById.setText(random);

            handler.postDelayed(this, 1000);
        }
    }
}