Chronometer - Android Widgets Example

package com.myapp;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.Button;
import android.widget.Chronometer;

import android.view.View;
import android.os.SystemClock;
import android.widget.Toast;

public class MainActivity extends Activity {
	
	Button btn1,btn2,btn3;
	Chronometer chmeter1;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
       
        
        // button1 Start 
        btn1 = (Button) findViewById(R.id.button1);
        btn1.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
            	chmeter1.start();
                showElapsedTime();
            }
        });      
        
        // button2 Stop
        btn2 = (Button) findViewById(R.id.button2);
        btn2.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
            	chmeter1.stop();
                showElapsedTime();
            }
        });     
        
        // button3 Reset
        btn3 = (Button) findViewById(R.id.button3);
        btn3.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
            	chmeter1.setBase(SystemClock.elapsedRealtime());
                showElapsedTime();
            }
        });   

        // chronometer1
        chmeter1 = (Chronometer) findViewById(R.id.chronometer1);
    }
    
    private void showElapsedTime() {
        long elapsedMillis = SystemClock.elapsedRealtime() - chmeter1.getBase();            
        Toast.makeText(MainActivity.this, "Elapsed milliseconds: " + elapsedMillis, 
                Toast.LENGTH_SHORT).show();
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    
}