CountDownTimer Android Tutorial

CountDownTimer

CountDownTimer is very useful class provided in android API Level 1.When you want timer,countdown functionality this CountDownTimer comes to help.We can avoid using Threads,TimerTask and Handlers for simple time counting task.CountDownTimer is very easy to use and implement.Also class methods post back results in the UI thread and very light weight class.

Example: Example Bellow shows simple timer that will update countdown every second.CountDownTimer can be easily used in more complex requirement.

Here is Implementing Activity:

import android.app.Activity; 
import android.os.Bundle;

import android.os.CountDownTimer;

import android.util.Log;

import android.view.View;

import android.widget.TextView;

public class StartActivity extends Activity

{

                private TextView count_down_text=null;

                private MyCountDownTimer countdowntimer=null;

               

                @Override

                protected void onCreate(Bundle savedInstanceState)

                {

                                super.onCreate(savedInstanceState);

                                setContentView(R.layout.keytalk_countdown_widget);

                                count_down_text=(TextView)findViewById(R.id.countdown_text);

                                countdowntimer=new MyCountDownTimer(10000, 1000);

                }

               

               

               

                public void startCountDown(View view)

                {

                                if(!countdowntimer.isRunning())

                                countdowntimer.startCountDown();

                                //can also directly countdowntimer.start()

                }

               

                public class MyCountDownTimer extends CountDownTimer

                {

                                    private long starttime;

                                    private boolean isrunning=false;

                               

                                                public MyCountDownTimer(long startTime, long interval)

                                                {

                                                               

                                                                super(startTime, interval);

                                                                this.starttime=startTime;

                                                }

               

                                                public void startCountDown()

                                                {

                                                                isrunning=true;

                                                                count_down_text.setVisibility(View.VISIBLE);

                                                                count_down_text.setText("" + starttime/1000);

                                                                Log.d("TAG"," starttime/1000:"+ starttime/1000);

                                                                start();

                                                }

                                               

                                                @Override

                                                public void onFinish()

                                                {

                                                                count_down_text.setVisibility(View.INVISIBLE);

                                                                isrunning=false;

                                                }

               

                                                @Override

                                                public void onTick(long millisUntilFinished)

                                                {

                                                                count_down_text.setText("" + millisUntilFinished/1000);

                                                }

                                               

                                                public boolean isRunning()

                                                {

                                                                return isrunning;

                                                }

                }

}

 Layout: 

You can use android button class to start the event:

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:background="@drawable/application_background">

   

    <com.swapmeen.customcomponent.CustomButton

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:background="@drawable/bluebutton"

      android:text="@string/start_countdown"

      android:textColor="#efdd44"

      android:textStyle="bold"

      android:paddingLeft="10dp"

      android:paddingRight="10dp"

      android:paddingTop="5dp"

      android:paddingBottom="5dp"

      android:textSize="18sp"

      android:layout_centerInParent="true"

      android:onClick="startCountDown"/>

   

       <TextView android:layout_width="wrap_content"

       android:layout_height="wrap_content"

       android:id="@+id/countdown_text"

       android:text="9"

       android:textStyle="bold"

       android:textColor="#FFFFFF"

       android:textSize="200sp"

       android:layout_centerInParent="true"

       android:visibility="invisible"

       />

         

         

</RelativeLayout>

 Screenshots of the application:

You can use CountDownTimer while implementing splash screens as well.I am coming with few more Easy to use but rarely used android classes which makes developers life easy in my next post stay tuned or subscribe my the blog.