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Set Alarm 8 clock in every day via android is not working

I am try to set Alarm 8am in every day to execute mainActivity , so this is my MainActivity:
protected void onCreate(Bundle savedInstanceState){
Intent Alarm = new Intent(MainActivity.this,LongRunningService.class);
startService(Alarm);
}
LongRunningService is Service :
AlarmManager manager = (AlarmManager) getSystemService(ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, 8);
calendar.set(Calendar.MINUTE, 00);
Intent i = new Intent(this,AlarmReceiver.class);
intent.setAction("startAlarm");
PendingIntent pi = PendingIntent.getBroadcast(this,0,i,0);
manager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),AlarmManager.INTERVAL_DAY, pi);
AlarmReceiver.java
public void onReceive(Context context, Intent intent){
if ("startAlarm".equals(intent.getAction()))
Log.d(TAG, "onReceive! "); //not working?
}
Log.d(TAG, "onReceive! "); //it's working

Source: which permissions an android application need in order to use the Alarm Manager Service?
It wakes CPU every 10 minutes until the phone turns off.
<uses-permission android:name="android.permission.WAKE_LOCK"></uses-permission>
<uses-permission android:name="com.android.alarm.permission.SET_ALARM"/>
<receiver android:process=":remote" android:name="Alarm"></receiver>
If you want set alarm repeating at phone boot time:
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED">
...
For more details : Alarm Manager Example
according to android documentation , you should use SET_ALARM permission
Documentation
Allows an application to broadcast an Intent to set an alarm for the
user.

I know what happen ,
Intent i = new Intent(this,AlarmReceiver.class);
intent.setAction("startAlarm"); //wrong
i.setAction("startAlarm"); //correct

Alarm Manager Android

private void startAlarm() {
AlarmManager alarmMgr;
PendingIntent alarmIntent;
alarmMgr = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(MainActivity.this, AlarmReceiver.class);
alarmIntent = PendingIntent.getBroadcast(MainActivity.this, 0, intent, 0);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, 23);
calendar.set(Calendar.MINUTE, 52);
alarmMgr.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
1000 * 60 * 20, alarmIntent);
}
startAlarm() method is in the MainActivity class.
The following code should display a toast (declared in onReceive() method of the AlarmReceiver class) at 23:52 and every 20 minutes thereafter
AlarmReceiver extends BroadcastReceiver.
The code compiles without errors but for some reason it is not displaying the toast.
NOTE : The code worked fine with ELAPSED_REALTIME_WAKEUP. I am having problem with RTC_WAKEUP only. So everything else has to be correct. There is something wrong inside the startAlarm() method only.

I have tried your code with some modification as below .
private void startAlarm() {
AlarmManager alarmMgr;
PendingIntent alarmIntent;
alarmMgr = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(MainActivity.this, AlarmReceiver.class);
alarmIntent = PendingIntent.getBroadcast(MainActivity.this, 0, intent, 0);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, 0);
calendar.set(Calendar.MINUTE, 2);
alarmMgr.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
1000 * 20, alarmIntent);
}
This code works fine with AlarmManager.RTC_WAKEUP. If it does not work for you, please reboot your device after installing it. After reboot completed, start your app. Then it should fire the alarm and every 20 sec interval the alarm fires repeatedly.
You can also check the difference between RTC_WAKEUP and ELAPSED_REALTIME_WAKEUP. From android docs, elapsedRealtime means, Returns milliseconds since boot, including time spent in sleep and RTC means, time in System.currentTimeMillis() (wall clock time in UTC).

Looks like You need to set an action to the intent:
Intent intent = new Intent(MainActivity.this, AlarmReceiver.class);
intent.setAction("YourPackageName.YourAction");
alarmIntent = PendingIntent.getBroadcast(MainActivity.this, 0, intent, 0);
And in the manifest:
<receiver android:name=".AlarmReciever">
<intent-filter>
<action android:name="YourPackageName.YourAction" />
</intent-filter>
</receiver>
This should fix the issue. You must have a unique action in the intent for use it with broadcast receiver.

how to start B class at every specific time on android?

I want use String start = "16:00"; in specific time, start another activity.
I must use String start = "16:00"
MainActivity.class
String start = "16:00";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setAlarmTime(this);
}
private void setAlarmTime(Context context) {
String[] strStart = start.split(":") // delete ":"
Calendar cal_start = Calendar.getInstance();
cal_start.set(Calendar.HOUR_OF_DAY, Integer.parseInt(strStart[0])); // hour
cal_start.set(Calendar.MINUTE, Integer.parseInt(strStart[1])); //minute
AlarmManager alarm = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(this, AlarmActivity.class);
PendingIntent pIntent = PendingIntent.getActivity(context, 0, intent, 0);
alarm.set(AlarmManager.RTC, cal_start.getTimeInMillis(), pIntent);
}
I want while the app is running, current time 4 o'clock , start AlarmActivity.class .
But it does not work.
How to every specific time start another activity on android?
#update
private void setAlarmTime(Context context) {
String[] strStart = start.split(":");
Calendar cal_start = Calendar.getInstance();
cal_start.set(Calendar.HOUR_OF_DAY, Integer.parseInt(strStart[0]));
cal_start.set(Calendar.MINUTE, Integer.parseInt(strStart[1]));
AlarmManager alarm = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);
alarm.set(AlarmManager.RTC_WAKEUP, cal_start.getTimeInMillis(), pendingIntent);
this source not work.
not work alarmManager.

Please consider to use AlarmManager.RTC_WAKEUP if you need to wake up the device even if it goes off.
alarm.set(AlarmManager.RTC_WAKEUP, cal_start.getTimeInMillis(), pIntent);
AlarmManager.RTC will NOT wake the device up.
Reference: https://developer.android.com/reference/android/app/AlarmManager.html#RTC
Btw, you do not need to pass the context reference to method:
PendingIntent pIntent = PendingIntent.getActivity(this /*can use this as it is a context already */ , 0, intent, 0);
Update:
Please also set the second and millisecond of the cal_start; otherwise it will be the values that you get the calendar instance.
cal_start.set(Calendar.SECOND, 0);
cal_start.set(Calendar.MILLISECOND, 0);
Update 2:
It works in my side, you may try to add
<uses-permission android:name="android.permission.WAKE_LOCK" />
in Manifests.
Btw, if you want this alarm repeat every day
AlarmManager alarm = (AlarmManager) getSystemService(ALARM_SERVICE);
alarm.setRepeating(AlarmManager.RTC_WAKEUP, cal_start.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pIntent);

Add this permission in your manifest
<uses-permission android:name="android.permission.WAKE_LOCK" />
register your receiver class in the application tag in the manifest file
<receiver android:name=".AlarmActivity" />
Resister your alarm that will trigger AlarmActivity at a specific time in your case its 16:00
Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.HOUR_OF_DAY, 16);
calendar.set(Calendar.MINUTE, 0);
calendar.set(Calendar.SECOND, 0);
Intent intent = new Intent(getApplicationContext(), AlarmActivity.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(getApplicationContext(), 100, intent, PendingIntent.FLAG_UPDATE_CURRENT);
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);
Make sure your register class extend BroadcastReceiver like this
class AlarmActivity extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// Do whatever you want
// you can generate notifications here
// or can start your application activity you want
}
}

Alarm Manager set Daily Alarm at a specific time?

I've been working on this application that is supposed to run at a given time daily, except on weekends. I've used an AlarmBroadCastReceiver to fire a certain block of code at a given time. I have this code in my AlarmBroadCastReceiver class:
public void SetAlarm(Context context) {
AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
intent.putExtra(ONE_TIME, Boolean.FALSE);
PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, 2);
calendar.set(Calendar.MINUTE, 30);
calendar.set(Calendar.SECOND, 0);
am.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 0, pi);
}
Basically I try and set a repeating alarm on that time.
Then at a press of a button, I have this in my MainActivity where I'm calling it from:
public void onStartAlarmClicked(View view){
Context context = this.getApplicationContext();
if(alarm != null){
Log.e(TAG, "starting alarm");
alarm.SetAlarm(context);
}else{
Log.e(TAG, "Alarm is null");
}
}
where alarm is an object of the AlarmBroadCastReceiver class.
The problem I have with it is that the code only fires once. Once it hits 2:30, it fires. However, when I set the time back to 2:29 and wait for 2:30, or set the date 1 day forward and then set the time to 2:20 and wait for 2:30, the code no longer fires.
I have a feeling I'm overlooking something rather simple with regards to setting the alarm time but I can't see it right now.

Found a better answer from this answer. Tweaked it a bit.
public void Set12nnAlarm(Context context) {
AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
intent.putExtra(ONE_TIME, Boolean.FALSE);
PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
// every day at 9 am
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
// if it's after or equal 9 am schedule for next day
if (Calendar.getInstance().get(Calendar.HOUR_OF_DAY) >= 9) {
Log.e(TAG, "Alarm will schedule for next day!");
calendar.add(Calendar.DAY_OF_YEAR, 1); // add, not set!
}
else{
Log.e(TAG, "Alarm will schedule for today!");
}
calendar.set(Calendar.HOUR_OF_DAY, 9);
calendar.set(Calendar.MINUTE, 0);
calendar.set(Calendar.SECOND, 0);
am.setInexactRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
AlarmManager.INTERVAL_DAY, pi);
}

You have to setup a BroadcastReceiver to listen to time and date changes, and then reset the alarm.
As you want the receiver to be triggered at all times, it is better to set in the Manifest.
Create class in own file
public class DateTimeChangeReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (action.equals(Intent.ACTION_TIME_CHANGED) ||
action.equals(Intent.ACTION_TIMEZONE_CHANGED) ||
action.equals(Intent.ACTION_DATE_CHANGED))
{
resetAlarm();
}
}
}
And in the Manifest
<receiver android:name=".DateTimeChangeReceiver ">
<intent_filter>
<action android:name="android.intent.action.TIMEZONE_CHANGED" />
<action android:name="android.intent.action.TIME_SET" />
<action android:name="android.intent.action.DATE_CHANGED" />
</intent_filter>
</receiver>

Cant get AlarmManager and broadcast working

No matter how I try, I cannot get the alarmManager and receiver to work - there seem to be SO many different ways to do it from what i've searched, but nothing seems to work.
I have in Manifest:
<receiver android:name="AlarmReceiver" />
I am using inner class for broadcastReceiver:
private class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Log.d("ALARM","TRIGGERED");
Notification(filteredList.get(0).getTitle());
}
}
I call function SetAlarm to start the manager:
private void SetAlarm(long time) {
AlarmManager alarm_mgr = (AlarmManager)(this.getSystemService( Context.ALARM_SERVICE ));
Intent intent = new Intent(MainActivity.this, AlarmReceiver.class);
//PendingIntent pi = PendingIntent.getService(MainActivity.this, 0, intent, 0);
PendingIntent pi = PendingIntent.getBroadcast(this, 111, intent, PendingIntent.FLAG_UPDATE_CURRENT);
Calendar calendar = Calendar.getInstance();
alarm_mgr.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pi);
Log.d("ALARMSET", "Alarm " + calendar.getTime().toString());
}
As you can see, in the receiver I have a notification call - I won't post because I know this works, but there is also a log that is not working.
For testing purposes I've set time to current time using the Calendar function.
You can see the pendingIntent, i have tried both getService and getBroadcast, I can't figure out which I need, but neither works anyway.
I'm sure I'm missing something, i don't know what, and I can't seem to find any answers at Google.
Is the AlarmReceiver ok as an inner class ? I have put it there because I need access to my "filteredList" List object.
thx

I am using inner class for broadcastReceiver:
This will not work. Android has to be able to create an instance of your BroadcastReceiver, and it cannot do so. At best, your BroadcastReceiver could be a static nested class, but then you would have to fix your manifest entry to refer to the outer class:
<receiver android:name="OuterClass$AlarmReceiver" />

No, actually the BroadcastReceiver needs to be public.Only then you can register it in manifest and access them. Place the AlarmReceiver code in a separate .java file. You will see the log inside the BroadcastReceiver.

try this
private AlarmManager alarmMgr;
private PendingIntent alarmIntent;
...
alarmMgr = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(context, AlarmReceiver.class);
alarmIntent = PendingIntent.getBroadcast(context, 0, intent, 0);
// Set the alarm to start at 8:30 a.m.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.set(Calendar.HOUR_OF_DAY, 8);
calendar.set(Calendar.MINUTE, 30);
// setRepeating() lets you specify a precise custom interval--in this case,
// 20 minutes.
alarmMgr.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
1000 * 60 * 20, alarmIntent);
For more details.. Look this

I stucked 1 day for this problem, and finally solved this.
AlarmManager is used to generate a broadcast every 30 seconds, and a broadcast receiver is used to receive the message and execute ...
So the main problem is the following 2 steps
1. In the AndroidManifist.xml a action filter needed.
<receiver android:name="com.istep.gps.straight.MyTimerReceiver">
<intent-filter>
<action android:name="com.istep.gps.straight.MyTimerReceiver.Action"/>
</intent-filter>
</receiver>
2. The most important is the Intent need to be empty, no AAA.class
private void initTimer(Context context) {
Intent intent = new Intent().setAction("com.istep.gps.straight.MyTimerReceiver.Action")
.putExtra("id",UniqueID.getID(context));
PendingIntent sender = PendingIntent.getBroadcast(context, 18, intent, 0);
AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
am.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime(), 1000 * 30, sender);
}

When you use calendar, you should setTimeInMillis
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());