Android - Timer Sample Code

Screen

Layout

<?xml version="1.0" encoding="utf-8"?>

<AbsoluteLayout

android:id="@+id/widget0"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

xmlns:android="http://schemas.android.com/apk/res/android"

>

<Button

android:id="@+id/btnStartTimer"

android:layout_width="77px"

android:layout_height="wrap_content"

android:text="Start"

android:layout_x="53px"

android:layout_y="156px"

>

</Button>

<TextView

android:id="@+id/myLabel"

android:layout_width="292px"

android:layout_height="27px"

android:text="TextView"

android:gravity="center"

android:layout_x="15px"

android:layout_y="55px"

>

</TextView>

<Button

android:id="@+id/btnStopTimer"

android:layout_width="74px"

android:layout_height="wrap_content"

android:text="Stop"

android:layout_x="175px"

android:layout_y="155px"

>

</Button>

</AbsoluteLayout>

Java Code

package com.mytimer;

import java.util.Calendar;

import android.app.Activity;

import android.os.Bundle;

import android.os.Handler;

import android.os.SystemClock;

import android.util.Log;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;

public class TimerSample extends Activity {

Handler mHandler = new Handler();

Button btnStartTimer;

Button btnStopTimer;

TextView txtMessage;

long mStartTime;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Log.i("TIMER_SAMPLE", "Creating objects for buttons");

btnStartTimer = (Button) findViewById(R.id.btnStartTimer);

btnStopTimer = (Button) findViewById(R.id.btnStopTimer);

Log.i("TIMER_SAMPLE", "Creating objects for textview");

txtMessage = (TextView) findViewById(R.id.myLabel);

Log.i("TIMER_SAMPLE", "Binding listeners for buttons");

btnStartTimer.setOnClickListener((OnClickListener) new startTimer());

btnStopTimer.setOnClickListener((OnClickListener) new stopTimer());

}

class startTimer implements Button.OnClickListener {

@Override

public void onClick(View v) {

Log.i("TIMER_SAMPLE", "Initialising timer");

if (mStartTime == 0L) {

Log.i("TIMER_SAMPLE", "Starting timer");

mStartTime = System.currentTimeMillis();

mHandler.removeCallbacks(mUpdateTimeTask);

mHandler.postDelayed(mUpdateTimeTask, 1000);

txtMessage.setText(getDateTime(mStartTime));

}

Log.i("TIMER_SAMPLE", "Timer started");

}

}

private Runnable mUpdateTimeTask = new Runnable() {

public void run() {

long timeInMillis = System.currentTimeMillis();

Log.i("TIMER_SAMPLE", "Timer updated " + getDateTime(timeInMillis));

txtMessage.setText(getDateTime(timeInMillis));

mHandler.postDelayed(this, 1000);

}

};

private String getDateTime(Long ms) {

Calendar cal = Calendar.getInstance();

cal.setTimeInMillis(ms);

java.util.Date date = cal.getTime();

return date.toString();

}

class stopTimer implements Button.OnClickListener {

@Override

public void onClick(View v) {

Log.i("TIMER_SAMPLE", "Stopping timer");

mHandler.removeCallbacks(mUpdateTimeTask);

}

}

}