Android AlarmManager

Apr 10, 2017 By: Dr. Droid Android Basics Comments: 37

Daily we used to set Alarms in our phone to wake up in morning or for some meetings, etc. I used to set lot of alarms for morning but unfortunately i used to wake up late only. 😛 So today we are going to learn about Alarms. Alarms (based on the AlarmManager class) give you a way to perform time-based operations outside the lifetime of your application. For example, you could use an alarm to initiate a long-running operation, such as starting a service once a day to download a weather forecast. You can schedule your application to run at a specific time in the future. It works whether your phone is running or not.

AlarmManager is having different characteristics mentioned below:

AlarmManager runs outside the lifetime of your application. Once an alarm is scheduled, it will invoke even when your application is not running or in sleep mode.
An scheduled alarm will execute unless it is stopped explicitly by calling cancel() method, or until device reboots.
All scheduled alarms will be stopped when device reboots. This means, you need to re-schedule them explicitly when device boot completes.
AlarmManger fires an Intent at given intervals. This can be used along with broadcast receivers to start a service to perform network operations.
AlarmManager is different form java Timer and TimerTask.

Android supports two clock types for alarm service; Elapsed real time and real time clock (RTC). Elapsed real time uses the time since device last booted. Real time clock (RTC) uses UTC time for alarm service clock. RTC is most commonly used for setting alarm service in android. The following example, using RTC to schedule alarm.

Prerequisite:

Example

In this tutorial, we will learn how to use AlarmManager that runs after a specific time provided by user.

VIDEO DEMO

1. Create a new project in Android Studio by navigating to File ⇒ New ⇒ New Project and fill required details. By default my activity is MainActivity.java.

2. Open res ⇒ values ⇒ strings.xml and add below string values. These are some strings that we are going to use in our project.

<resources>
    <string name="app_name">Alarm Manager Demo</string>
    <string name="stop_alarm">Stop Alarm</string>
    <string name="start_alarm">Start Alarm</string>
    <string name="edit_text_hint">Input your Alarm time</string>
    <string name="hours">Hours</string>
    <string name="minutes">Minutes</string>
    <string name="seconds">Seconds</string>
    <string name="label">Select your Alarm input type from below:</string>
</resources>

<string name="app_name">Alarm Manager Demo</string>

<string name="stop_alarm">Stop Alarm</string>

<string name="start_alarm">Start Alarm</string>

<string name="edit_text_hint">Input your Alarm time</string>

<string name="hours">Hours</string>

<string name="minutes">Minutes</string>

<string name="seconds">Seconds</string>

<string name="label">Select your Alarm input type from below:</string>

</resources>

3. Open your activity_main.xml layout and place the below code to it. The layout contains some RadioButton, Edit Text and Button.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="10dp"
    tools:context="com.alarmmanager_demo.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/label"
        android:textColor="@android:color/white"
        android:textSize="13sp" />

    <RadioGroup
        android:id="@+id/time_type_selection_radio_group"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="horizontal"
        android:padding="5dp">

        <RadioButton
            android:id="@+id/seconds_radio_button"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:checked="true"
            android:gravity="center_vertical"
            android:text="@string/seconds"
            android:textColor="@android:color/white" />

        <RadioButton
            android:id="@+id/minutes_radio_button"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center_vertical"
            android:text="@string/minutes"
            android:textColor="@android:color/white" />

        <RadioButton
            android:id="@+id/hours_radio_button"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center_vertical"
            android:text="@string/hours"
            android:textColor="@android:color/white" />
    </RadioGroup>

    <EditText
        android:id="@+id/input_interval_time"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="@string/edit_text_hint"
        android:inputType="number"
        android:padding="10dp"
        android:textColor="@android:color/white"
        android:textColorHint="@android:color/darker_gray"
        android:textSize="14sp" />

    <Button
        android:id="@+id/start_alarm_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:background="@color/colorPrimary"
        android:text="@string/start_alarm"
        android:textColor="@android:color/white"
        android:textSize="14sp" />

    <Button
        android:id="@+id/stop_alarm_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:background="@color/colorPrimary"
        android:text="@string/stop_alarm"
        android:textColor="@android:color/white"
        android:textSize="14sp" />
</LinearLayout>

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

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

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="vertical"

android:padding="10dp"

tools:context="com.alarmmanager_demo.MainActivity">

<TextView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/label"

android:textColor="@android:color/white"

android:textSize="13sp" />

<RadioGroup

android:id="@+id/time_type_selection_radio_group"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:gravity="center"

android:orientation="horizontal"

android:padding="5dp">

<RadioButton

android:id="@+id/seconds_radio_button"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_weight="1"

android:checked="true"

android:gravity="center_vertical"

android:text="@string/seconds"

android:textColor="@android:color/white" />

<RadioButton

android:id="@+id/minutes_radio_button"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center_vertical"

android:text="@string/minutes"

android:textColor="@android:color/white" />

<RadioButton

android:id="@+id/hours_radio_button"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center_vertical"

android:text="@string/hours"

android:textColor="@android:color/white" />

</RadioGroup>

<EditText

android:id="@+id/input_interval_time"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:hint="@string/edit_text_hint"

android:inputType="number"

android:padding="10dp"

android:textColor="@android:color/white"

android:textColorHint="@android:color/darker_gray"

android:textSize="14sp" />

<Button

android:id="@+id/start_alarm_button"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginTop="10dp"

android:background="@color/colorPrimary"

android:text="@string/start_alarm"

android:textColor="@android:color/white"

android:textSize="14sp" />

<Button

android:id="@+id/stop_alarm_button"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginTop="10dp"

android:background="@color/colorPrimary"

android:text="@string/stop_alarm"

android:textColor="@android:color/white"

android:textSize="14sp" />

</LinearLayout>

4. Now create Broadcast Receiver java class naming AlarmReceiver.java which will invoke by AlarmManger. Here you can do your task like I am running AlarmSound by starting a service and also displaying a Notification.

package com.alarmmanager_demo;

import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

import static android.support.v4.content.WakefulBroadcastReceiver.startWakefulService;

/**
 * Created by sonu on 09/04/17.
 */

public class AlarmReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Toast.makeText(context, "ALARM!! ALARM!!", Toast.LENGTH_SHORT).show();

        //Stop sound service to play sound for alarm
        context.startService(new Intent(context, AlarmSoundService.class));

        //This will send a notification message and show notification in notification tray
        ComponentName comp = new ComponentName(context.getPackageName(),
                AlarmNotificationService.class.getName());
        startWakefulService(context, (intent.setComponent(comp)));

    }


}

package com.alarmmanager_demo;

import android.content.BroadcastReceiver;

import android.content.ComponentName;

import android.content.Context;

import android.content.Intent;

import android.widget.Toast;

import static android.support.v4.content.WakefulBroadcastReceiver.startWakefulService;

/**

* Created by sonu on 09/04/17.

public class AlarmReceiver extends BroadcastReceiver {

@Override

public void onReceive(Context context, Intent intent) {

Toast.makeText(context, "ALARM!! ALARM!!", Toast.LENGTH_SHORT).show();

//Stop sound service to play sound for alarm

context.startService(new Intent(context, AlarmSoundService.class));

//This will send a notification message and show notification in notification tray

ComponentName comp = new ComponentName(context.getPackageName(),

AlarmNotificationService.class.getName());

startWakefulService(context, (intent.setComponent(comp)));

}

5. Let us have a look into MainActivity.java file. In this class, we have defined two simple methods triggerAlarmManager(int alarmTriggerTime) and stopAlarmManager().

Retrieve PendingIntent : These two lines of use to get the PendingIntent of AlarmReceiver broadcast receiver.

    /* Retrieve a PendingIntent that will perform a broadcast */
        Intent alarmIntent = new Intent(MainActivity.this, AlarmReceiver.class);
        pendingIntent = PendingIntent.getBroadcast(MainActivity.this, ALARM_REQUEST_CODE, alarmIntent, 0);

/* Retrieve a PendingIntent that will perform a broadcast */

Intent alarmIntent = new Intent(MainActivity.this, AlarmReceiver.class);

pendingIntent = PendingIntent.getBroadcast(MainActivity.this, ALARM_REQUEST_CODE, alarmIntent, 0);

Trigger AlarmManager :triggerAlarmManager(int alarmTriggerTime) method use to set the AlarmManager at particular time that we pass in parameter.

 //Trigger alarm manager with entered time interval
    public void triggerAlarmManager(int alarmTriggerTime) {
        // get a Calendar object with current time
        Calendar cal = Calendar.getInstance();
        // add alarmTriggerTime seconds to the calendar object
        cal.add(Calendar.SECOND, alarmTriggerTime);

        AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);//get instance of alarm manager
        manager.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), pendingIntent);//set alarm manager with entered timer by converting into milliseconds

        Toast.makeText(this, "Alarm Set for " + alarmTriggerTime + " seconds.", Toast.LENGTH_SHORT).show();
    }

//Trigger alarm manager with entered time interval

public void triggerAlarmManager(int alarmTriggerTime) {

// get a Calendar object with current time

Calendar cal = Calendar.getInstance();

// add alarmTriggerTime seconds to the calendar object

cal.add(Calendar.SECOND, alarmTriggerTime);

AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);//get instance of alarm manager

manager.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), pendingIntent);//set alarm manager with entered timer by converting into milliseconds

Toast.makeText(this, "Alarm Set for " + alarmTriggerTime + " seconds.", Toast.LENGTH_SHORT).show();

}

Stop AlarmManager :stopAlarmManager() method use to stop any running alarm. As I am playing sound and displaying notification as well so i am stopping the sound and cancelling the notification respectively.

 //Stop/Cancel alarm manager
    public void stopAlarmManager() {

        AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
        manager.cancel(pendingIntent);//cancel the alarm manager of the pending intent


        //Stop the Media Player Service to stop sound
        stopService(new Intent(MainActivity.this, AlarmSoundService.class));

        //remove the notification from notification tray
        NotificationManager notificationManager = (NotificationManager) this
                .getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.cancel(AlarmNotificationService.NOTIFICATION_ID);

        Toast.makeText(this, "Alarm Canceled/Stop by User.", Toast.LENGTH_SHORT).show();
    }

//Stop/Cancel alarm manager

public void stopAlarmManager() {

AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);

manager.cancel(pendingIntent);//cancel the alarm manager of the pending intent

//Stop the Media Player Service to stop sound

stopService(new Intent(MainActivity.this, AlarmSoundService.class));

//remove the notification from notification tray

NotificationManager notificationManager = (NotificationManager) this

.getSystemService(Context.NOTIFICATION_SERVICE);

notificationManager.cancel(AlarmNotificationService.NOTIFICATION_ID);

Toast.makeText(this, "Alarm Canceled/Stop by User.", Toast.LENGTH_SHORT).show();

}

Final Source Code

package com.alarmmanager_demo;

import android.app.AlarmManager;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    //Pending intent instance
    private PendingIntent pendingIntent;

    private RadioButton secondsRadioButton, minutesRadioButton, hoursRadioButton;

    //Alarm Request Code
    private static final int ALARM_REQUEST_CODE = 133;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //Find id of all radio buttons
        secondsRadioButton = (RadioButton) findViewById(R.id.seconds_radio_button);
        minutesRadioButton = (RadioButton) findViewById(R.id.minutes_radio_button);
        hoursRadioButton = (RadioButton) findViewById(R.id.hours_radio_button);

        /* Retrieve a PendingIntent that will perform a broadcast */
        Intent alarmIntent = new Intent(MainActivity.this, AlarmReceiver.class);
        pendingIntent = PendingIntent.getBroadcast(MainActivity.this, ALARM_REQUEST_CODE, alarmIntent, 0);

        //Find id of Edit Text
        final EditText editText = (EditText) findViewById(R.id.input_interval_time);

        //Set On CLick over start alarm button
        findViewById(R.id.start_alarm_button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String getInterval = editText.getText().toString().trim();//get interval from edittext

                //check interval should not be empty and 0
                if (!getInterval.equals("") && !getInterval.equals("0"))
                    //finally trigger alarm manager
                    triggerAlarmManager(getTimeInterval(getInterval));

            }
        });

        //set on click over stop alarm button
        findViewById(R.id.stop_alarm_button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //Stop alarm manager
                stopAlarmManager();
            }
        });

    }

    //get time interval to trigger alarm manager
    private int getTimeInterval(String getInterval) {
        int interval = Integer.parseInt(getInterval);//convert string interval into integer

        //Return interval on basis of radio button selection
        if (secondsRadioButton.isChecked())
            return interval;
        if (minutesRadioButton.isChecked())
            return interval * 60;//convert minute into seconds
        if (hoursRadioButton.isChecked()) return interval * 60 * 60;//convert hours into seconds

        //else return 0
        return 0;
    }


    //Trigger alarm manager with entered time interval
    public void triggerAlarmManager(int alarmTriggerTime) {
        // get a Calendar object with current time
        Calendar cal = Calendar.getInstance();
        // add alarmTriggerTime seconds to the calendar object
        cal.add(Calendar.SECOND, alarmTriggerTime);

        AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);//get instance of alarm manager
        manager.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), pendingIntent);//set alarm manager with entered timer by converting into milliseconds

        Toast.makeText(this, "Alarm Set for " + alarmTriggerTime + " seconds.", Toast.LENGTH_SHORT).show();
    }

    //Stop/Cancel alarm manager
    public void stopAlarmManager() {

        AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
        manager.cancel(pendingIntent);//cancel the alarm manager of the pending intent


        //Stop the Media Player Service to stop sound
        stopService(new Intent(MainActivity.this, AlarmSoundService.class));

        //remove the notification from notification tray
        NotificationManager notificationManager = (NotificationManager) this
                .getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.cancel(AlarmNotificationService.NOTIFICATION_ID);

        Toast.makeText(this, "Alarm Canceled/Stop by User.", Toast.LENGTH_SHORT).show();
    }
}

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package com.alarmmanager_demo;

import android.app.AlarmManager;

import android.app.NotificationManager;

import android.app.PendingIntent;

import android.content.Context;

import android.content.Intent;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.view.View;

import android.widget.EditText;

import android.widget.RadioButton;

import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

//Pending intent instance

private PendingIntent pendingIntent;

private RadioButton secondsRadioButton, minutesRadioButton, hoursRadioButton;

//Alarm Request Code

private static final int ALARM_REQUEST_CODE = 133;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

//Find id of all radio buttons

secondsRadioButton = (RadioButton) findViewById(R.id.seconds_radio_button);

minutesRadioButton = (RadioButton) findViewById(R.id.minutes_radio_button);

hoursRadioButton = (RadioButton) findViewById(R.id.hours_radio_button);

/* Retrieve a PendingIntent that will perform a broadcast */

Intent alarmIntent = new Intent(MainActivity.this, AlarmReceiver.class);

pendingIntent = PendingIntent.getBroadcast(MainActivity.this, ALARM_REQUEST_CODE, alarmIntent, 0);

//Find id of Edit Text

final EditText editText = (EditText) findViewById(R.id.input_interval_time);

//Set On CLick over start alarm button

findViewById(R.id.start_alarm_button).setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

String getInterval = editText.getText().toString().trim();//get interval from edittext

//check interval should not be empty and 0

if (!getInterval.equals("") && !getInterval.equals("0"))

//finally trigger alarm manager

triggerAlarmManager(getTimeInterval(getInterval));

}

});

//set on click over stop alarm button

findViewById(R.id.stop_alarm_button).setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

//Stop alarm manager

stopAlarmManager();

}

});

}

//get time interval to trigger alarm manager

private int getTimeInterval(String getInterval) {

int interval = Integer.parseInt(getInterval);//convert string interval into integer

//Return interval on basis of radio button selection

if (secondsRadioButton.isChecked())

return interval;

if (minutesRadioButton.isChecked())

return interval * 60;//convert minute into seconds

if (hoursRadioButton.isChecked()) return interval * 60 * 60;//convert hours into seconds

//else return 0

return 0;

}

//Trigger alarm manager with entered time interval

public void triggerAlarmManager(int alarmTriggerTime) {

// get a Calendar object with current time

Calendar cal = Calendar.getInstance();

// add alarmTriggerTime seconds to the calendar object

cal.add(Calendar.SECOND, alarmTriggerTime);

AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);//get instance of alarm manager

manager.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), pendingIntent);//set alarm manager with entered timer by converting into milliseconds

Toast.makeText(this, "Alarm Set for " + alarmTriggerTime + " seconds.", Toast.LENGTH_SHORT).show();

}

//Stop/Cancel alarm manager

public void stopAlarmManager() {

AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);

manager.cancel(pendingIntent);//cancel the alarm manager of the pending intent

//Stop the Media Player Service to stop sound

stopService(new Intent(MainActivity.this, AlarmSoundService.class));

//remove the notification from notification tray

NotificationManager notificationManager = (NotificationManager) this

.getSystemService(Context.NOTIFICATION_SERVICE);

notificationManager.cancel(AlarmNotificationService.NOTIFICATION_ID);

Toast.makeText(this, "Alarm Canceled/Stop by User.", Toast.LENGTH_SHORT).show();

}

6. As we started sound service in AlarmReceiver.java class, so now create a AlarmSoundService.java class extending with Service. This class will use to play the alarm sound in onCreate() and stop the sound in onDestroy() when user stops the Alarm.

You can download the Alarm Sound mp3 file from this link. Its a good website for Alarm Sounds.

package com.alarmmanager_demo;

import android.app.Service;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.IBinder;
import android.support.annotation.Nullable;

/**
 * Created by sonu on 10/04/17.
 */

public class AlarmSoundService extends Service {
    private MediaPlayer mediaPlayer;

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();

        //Start media player
        mediaPlayer = MediaPlayer.create(this, R.raw.alarm_sound);
        mediaPlayer.start();
        mediaPlayer.setLooping(true);//set looping true to run it infinitely
    }

    @Override
    public void onDestroy() {
        super.onDestroy();

        //On destory stop and release the media player
        if (mediaPlayer != null && mediaPlayer.isPlaying()) {
            mediaPlayer.stop();
            mediaPlayer.reset();
            mediaPlayer.release();
        }
    }
}

package com.alarmmanager_demo;

import android.app.Service;

import android.content.Intent;

import android.media.MediaPlayer;

import android.os.IBinder;

import android.support.annotation.Nullable;

/**

* Created by sonu on 10/04/17.

public class AlarmSoundService extends Service {

private MediaPlayer mediaPlayer;

@Nullable

@Override

public IBinder onBind(Intent intent) {

return null;

}

@Override

public void onCreate() {

super.onCreate();

//Start media player

mediaPlayer = MediaPlayer.create(this, R.raw.alarm_sound);

mediaPlayer.start();

mediaPlayer.setLooping(true);//set looping true to run it infinitely

}

@Override

public void onDestroy() {

super.onDestroy();

//On destory stop and release the media player

if (mediaPlayer != null && mediaPlayer.isPlaying()) {

mediaPlayer.stop();

mediaPlayer.reset();

mediaPlayer.release();

}

7. Also we are displaying Notification when Alarm starts so lets create new java class naming AlarmNotificationService.java and extend it with IntentService. This class used to show notification.

package com.alarmmanager_demo;

import android.app.IntentService;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.support.v4.app.NotificationCompat;

/**
 * Created by sonu on 10/04/17.
 */

public class AlarmNotificationService extends IntentService {
    private NotificationManager alarmNotificationManager;

    //Notification ID for Alarm
    public static final int NOTIFICATION_ID = 1;

    public AlarmNotificationService() {
        super("AlarmNotificationService");
    }

    @Override
    public void onHandleIntent(Intent intent) {

        //Send notification
        sendNotification("Wake Up! Wake Up! Alarm started!!");
    }

    //handle notification
    private void sendNotification(String msg) {
        alarmNotificationManager = (NotificationManager) this
                .getSystemService(Context.NOTIFICATION_SERVICE);

        //get pending intent
        PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
                new Intent(this, MainActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);

        //Create notification
        NotificationCompat.Builder alamNotificationBuilder = new NotificationCompat.Builder(
                this).setContentTitle("Alarm").setSmallIcon(R.mipmap.ic_launcher)
                .setStyle(new NotificationCompat.BigTextStyle().bigText(msg))
                .setContentText(msg).setAutoCancel(true);
        alamNotificationBuilder.setContentIntent(contentIntent);

        //notiy notification manager about new notification
        alarmNotificationManager.notify(NOTIFICATION_ID, alamNotificationBuilder.build());
    }


}

package com.alarmmanager_demo;

import android.app.IntentService;

import android.app.NotificationManager;

import android.app.PendingIntent;

import android.content.Context;

import android.content.Intent;

import android.support.v4.app.NotificationCompat;

/**

* Created by sonu on 10/04/17.

public class AlarmNotificationService extends IntentService {

private NotificationManager alarmNotificationManager;

//Notification ID for Alarm

public static final int NOTIFICATION_ID = 1;

public AlarmNotificationService() {

super("AlarmNotificationService");

}

@Override

public void onHandleIntent(Intent intent) {

//Send notification

sendNotification("Wake Up! Wake Up! Alarm started!!");

}

//handle notification

private void sendNotification(String msg) {

alarmNotificationManager = (NotificationManager) this

.getSystemService(Context.NOTIFICATION_SERVICE);

//get pending intent

PendingIntent contentIntent = PendingIntent.getActivity(this, 0,

new Intent(this, MainActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);

//Create notification

NotificationCompat.Builder alamNotificationBuilder = new NotificationCompat.Builder(

this).setContentTitle("Alarm").setSmallIcon(R.mipmap.ic_launcher)

.setStyle(new NotificationCompat.BigTextStyle().bigText(msg))

.setContentText(msg).setAutoCancel(true);

alamNotificationBuilder.setContentIntent(contentIntent);

//notiy notification manager about new notification

alarmNotificationManager.notify(NOTIFICATION_ID, alamNotificationBuilder.build());

}

8. Also don’t forget to declare BroadCastReceiver, Service and IntentService in Manifest file and as we are showing notification with WAKE_LOCK so use the android.permission.WAKE_LOCK permission. Your AndroidManifest.xml will look like as below.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.alarmmanager_demo">

    <!--  Permission required to Waking Lock if device screen is off  -->
    <uses-permission android:name="android.permission.WAKE_LOCK" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <!--  Declare  Alarm Broadcast receiver here  -->
        <receiver android:name=".AlarmReceiver" />

        <!--  Declare  Alarm Notification Service here  -->
        <service android:name=".AlarmNotificationService" />

        <!--  Declare  Alarm Sound Service here  -->
        <service android:name=".AlarmSoundService" />
    </application>

</manifest>

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

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

package="com.alarmmanager_demo">

<uses-permission android:name="android.permission.WAKE_LOCK" />

<application

android:allowBackup="true"

android:icon="@mipmap/ic_launcher"

android:label="@string/app_name"

android:roundIcon="@mipmap/ic_launcher_round"

android:supportsRtl="true"

android:theme="@style/AppTheme">

<intent-filter>

</intent-filter>

</activity>

</application>

</manifest>

9. Finally all done, now you can also make apps with AlarmManager.

Thanks.

37 Comments

Crsitofer

Tuesday, June 27th, 2017

What Android OS version are you using? because I added a reminder for one of my app, it is working well in Pre Nougat versión but in Nougat version the dayInterval is not working!

Dr. Droid

Tuesday, June 27th, 2017

Hi Cristofer,

I am using Marshmallow OS Version for testing. I have not tested in Nougat OS Devices.

Thanks.

Vijay

Thursday, August 17th, 2017

How to trigger the alarm for every 5 seconds. I want to hit my server every 5 secs. Can you give me sample for that?

Dr. Droid

Friday, August 18th, 2017

Hi Vijay,

Please see the article by clicking below link:
https://www.androhub.com/android-image-slider-using-viewpager/

In this article I am using TIMER inside MainActivity.java to slide the images after 3 sec. So you can also use that TIMER code to hit your server after 5 sec by changing the value.

Thanks

vikas joshi

Sunday, September 24th, 2017

can you tell me
how to can pick image compressed to gallery
like whats up profile set gallery

Dr. Droid

Monday, September 25th, 2017

Hi Vikas Joshi,

For picking image from gallery see this article : https://www.androhub.com/select-and-share-multiple-images/

To compress image visit this link : https://stackoverflow.com/questions/18545246/how-to-compress-image-size

Thanks

INDRAKANTH

Thursday, November 9th, 2017

Hi,
I slightly modified this code to do a periodic task by broadcasting the alarm receiver class for every 30 mins from alarm notifier service class.
Butt after 3-4 intervals it stopped showing notifications. May I know the reason for that

Dr. Droid

Thursday, November 9th, 2017

Hi Indrakanth,

Can you please share your changes so that i can see what is creating the issue.

Thanks

INDRAKANTH

Friday, November 10th, 2017

I have downloaded your sample and modified AlarmReceiver and AlarmNotificationService only to implement periodic notification.
Below are my changes.
AlarmReceiver.java:
In Onreceive() i commented out the alarmSoundService to get only notification.

Toast.makeText(context, “ALARM!! ALARM!!”, Toast.LENGTH_SHORT).show();
//Stop sound service to play sound for alarm
//context.startService(new Intent(context, AlarmSoundService.class));
//This will send a notification message and show notification in notification tray
ComponentName comp = new ComponentName(context.getPackageName(),
AlarmNotificationService.class.getName());
startWakefulService(context, (intent.setComponent(comp)));

Changes in AlarmNotificationService: I wrote the code to broadcast the alarmReceiver for every 30mins.
public void onHandleIntent(Intent intent) {
Calendar cal = Calendar.getInstance();
Intent alarmIntent = new Intent(AlarmNotificationService.this, AlarmReceiver.class);
pendingIntent = PendingIntent.getBroadcast(AlarmNotificationService.this, 133, alarmIntent, 0);
cal.add(Calendar.MINUTE,30);
AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);//get instance of alarm manager
manager.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), pendingIntent);//set alarm manager with entered timer by converting into milliseconds
//Send notification
sendNotification(“Wake Up! Wake Up! Alarm started!!”);
}

INDRAKANTH

Friday, November 10th, 2017

I already shared the sample
But not sure why it is not showing here even though it generated a comment number successfully

INDRAKANTH

Friday, November 10th, 2017

//Stop sound service to play sound for alarm
//context.startService(new Intent(context, AlarmSoundService.class))
//This will send a notification message and show notification in notification tray
ComponentName comp = new ComponentName(context.getPackageName(),
AlarmNotificationService.class.getName())
startWakefulService(context, (intent.setComponent(comp)))

Changes in AlarmNotificationService: I wrote the code to broadcast the alarmReceiver for every 30mins.
public void onHandleIntent(Intent intent)
Calendar cal = Calendar.getInstance()
Intent alarmIntent = new Intent(AlarmNotificationService.this, AlarmReceiver.class)
pendingIntent = PendingIntent.getBroadcast(AlarmNotificationService.this, 133, alarmIntent, 0)
cal.add(Calendar.MINUTE,30)
AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE)//get instance of alarm manager
manager.set(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), pendingIntent)//set alarm manager with entered timer by converting into milliseconds
//Send notification
sendNotification(“Wake Up Wake Up Alarm started”)

Dr. Droid

Friday, November 10th, 2017

Hi Indrakanth,

You need to use setRepeating() method instead of set(). I am sharing some links for your reference so that you can check the code and implement it in correct way.

1. https://stackoverflow.com/questions/22189283/how-to-set-time-for-repeating-alarm-for-every-15-mints-in-android
2. https://stackoverflow.com/questions/26573341/scheduling-alarm-every-2-minutes-android

Hope it will help you.

Thanks

INDRAKANTH

Friday, November 10th, 2017

Hi
I modified the main activity.java from set to set repeating as suggested and gave the interval that we sepcify in this demo as frequency.
I commented the setlooping true as the alarm will ring and stop on its own.
Everything worked fine till 7hrs i.e for 14 intervals. After that I went to a meeting where I left the mobile idle at desk for more than 1hr. After that there are no notifications?
Not sure why?

Dr. Droid

Friday, November 10th, 2017

Hi Indrakanth,

This is strange issue.
Can you please tell me in which device you are testing the app with OS Version?

So that i can do some research for you. And you also do some research about this strange issue.

Thanks

INDRAKANTH

Friday, November 10th, 2017

I am using Xiaomi mi Redmi 3s prime mobile with android 6.0.1 with an miui version miui global 8.5.
I have been investigating this issue from past 2months. I observed this similar behavior in letv le2 mobiles too.

Dr. Droid

Friday, November 10th, 2017

Hi Indrakanth,

If possible can you test in any other device like Samsung or Moto so that we can conclude that it is working on all devices or in some devices it is creating issue.

Thanks

INDRAKANTH

Friday, November 10th, 2017

I tested similar functionality on Moto device and found that it stopped working after a day. But I will install your demo sample with my changes on the Moto device and let u know in 2 days. In mean while I would like you too continue analysis on this

INDRAKANTH

Monday, November 13th, 2017

Hi
I tested this on xperia mobile which is working on android 7.1.1 and observed that it is working fine, I believe that the problem is with non pure android version mobiles. Is there any workaround /solution to handle this issue.

Dr. Droid

Monday, November 20th, 2017

Hi Indrakanth,

I found one library which is very great for all the API levels.

https://github.com/evernote/android-job

Implement this library and it will handle everything.

Thanks

wesley

Thursday, September 6th, 2018

como faço para salvar vários alarmes?

Dr. Droid

Friday, September 7th, 2018

Hi Wesley,

Crie várias instâncias de alarme.

Thanks

Tongdee

Friday, January 18th, 2019

Hi Dr.
I am tongdee ,be a housekeeper,and want to be gardener .would you mind to discuss ” How can i take picture and up load it to internet and can see it on phone or computer”
thank.

Dr. Droid

Wednesday, January 23rd, 2019

Hi Tongdee,

Can you mail me your requirements so that I can guide you properly.

Thanks

Maico

Tuesday, February 26th, 2019

Sir good day. Thank you for your example it really helped me with my project but there’s only one thing i cannot solve, the alarm is working fine but when i try to turn off the phone/get the battery to test if the alarm will still continue after turning it on and it doesn’t and that’s my problem please help me with this Sir. Thank you

Maico

Tuesday, February 26th, 2019

Sir how the app is working fine but it wont alarm when the phone turned off, after turning on the it doesn’t alarm anymore.
Please help me Sir. Thank You so much

Dr. Droid

Tuesday, February 26th, 2019

Hi Maico,

To start the alarm again when you restart your device. You have to listen BOOT_COMPLETED broadcast to start the service again.

Check this link for help.

Thanks

Rose

Sunday, March 31st, 2019

Hello, how do i add R.raw.alarm_sound in AlarmSoundService class in android studio. Since it is giving me an error of cannot resolve symbol ‘raw’. How do i solve this?

Rose Stacy

Monday, April 1st, 2019

Hello,
how do i add notification sound from the link you provided to AlarmSoundService class. Since
mediaPlayer = MediaPlayer.create(this, R.raw.alarm_sound); when i put this code it is giving me an error on raw. saying it can not resolve this. How do i solve this?

Dr. Droid

Wednesday, April 3rd, 2019

Hi Rose,

Have you created raw directory and kept the sound file into it?

Thanks

Stacy

Tuesday, April 2nd, 2019

hello,
i have followed your code but when i press start button i get a message of alarm is set for 2 seconds, then i get null pointer exception error, that the app has stopped.

How do i solve this?

Dr. Droid

Wednesday, April 3rd, 2019

Hi Stacy,

Null pointer exception occurs when something is not initialised. So cross check your code and check which one is not initialised.

Thanks

MariannaTD

Saturday, August 3rd, 2019

Hello!! i am following your example but in the BroadcastReceiver when i use the library WakefulBroadcastReceiver doesnt work, says that doesnt have the library anymore. Is there another library that works the same as this library or something? i’ll really appreciate your response !! Thank you for your work

Dr. Droid

Monday, August 12th, 2019

Hi Marianna TD,

WakefulBroadcastReceiver has been deprecated and Android discourage to use it. You can check the replacement here: https://stackoverflow.com/questions/47217345/wakefulbroadcastreceiver-is-deprecated.

Thanks

Chirag Prajapati

Friday, January 24th, 2020

Hello, I want some help from you.

I have created reminder app and I used Work manager, Job scheduler & Firebase JobDispater but It will not exacute on exact time which I have given the job. I really don’t know that How can I manage my all reminder in app. I heard that Alarm Manager is not supported in newer version? Is it right?

Can you please tell me about How can I schedule reminders? And It must be execute on given time.

Please answer fast as possible.
Thank you.

Dr. Droid

Friday, January 24th, 2020

Hi Chirag,

Still, you can use alarm manager see this link: https://developer.android.com/training/scheduling/alarms
Only the methods have changed.

And due to the doze mode and app standby, the alarms can be delayed.

Thanks

Nikki

Sunday, October 24th, 2021

hi i noticed that the alarm manager notification is only work for android 6.0, can you help me how can i also notified it to android 8.0 and higher?

thank you

Dr. Droid

Monday, October 25th, 2021

Hi Nikki,

Here are a few links that might help you:

https://developer.android.com/training/scheduling/alarms

https://newbedev.com/localnotification-with-alarmmanager-and-broadcastreceiver-not-firing-up-in-android-o-oreo

https://medium.com/@benexus/background-services-in-android-o-862121d96c95

https://stackoverflow.com/questions/46304839/android-8-0-oreo-alarmmanager-with-broadcast-receiver-and-implicit-broadcast-ban

Thanks