In my app, I need to add a row to a database and simultaniously set up an Alarm event to repeat every day at the time specified in one of the database columns. I already have some code, but it doesent trigger the alarm event at the specified time. Here is my code:
public class Add_reminder extends Activity {
AlarmManager am;
int hours, minutes;
REMIND_DB db;
Calendar calendar;
Cursor cursor;
Button button;
public void onCreate(Bundle savedInstanceState) {
//The usual code in the beginning of onCreate
//I load db from extended Application class as global since i use it in more
//Activities. Ints hours and minutes is set by user interaction
calendar = Calendar.getInstance();
am = (AlarmManager) getSystemService(ALARM_SERVICE);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
db.open();
db.insertReminder( -- parameters for database --);
cursor = db.getAllReminders();
cursor.moveToLast();
calendar.set(Calendar.HOUR, hours);
calendar.set(Calendar.MINUTE, minutes);
Intent intent = new Intent(Add_reminder.this, ReminderAlarm.class);
intent.putExtra("id_of_db_row", cursor.getInt(0));
PendingIntent pi = PendingIntent.getActivity(Add_reminder.this,
cursor.getInt(0), intent, PendingIntent.FLAG_CANCEL_CURRENT);
am.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
24*3600*1000, pi);
db.close()
}
});
}
}
Database is updated correctly, but the ReminderActivity never starts on specified time. I dont know what could be wrong. I saw some example codes using BroadcastReceiver instead of starting the Activity right on with the PendingIntent, but this should work too, right? Does anyone knows what could be wrong?
My second question is if Im going to need the same instance of AlarmManager when I want to add or remove some alarms from a different Activity, or do I just declare another AlarmManager in every Activity I need?
Thank you!
You should use a broadcast receiver for alarms, and then start a service that does the actual work. Broadcast receivers shouldn't block the UI thread with lengthy operations (such as writing to the DB). Additionally, 'once a day' alarms might be problematic: if the user reboots the phone: registered alarms will be lost. You need to:
save the time the alarm is supposed to run to, say, SharedPreferecnes
re-register your alarm when the phone boots (receive the BOOT_COMPLETED broadcast)
don't use setRepeating() but let each alarm register the next on
Using a shorter period (1 or 2 minutes) for testing also helps.
As for the AlarmManager instance, it's a system service, you don't need to care about what instance you are using. Just get it using getSystemService()
Related
I am busy working on a daily quote app. I have a ListView inside of my MainActivity class that displays one daily quote from a local SQLite Database. That works. I need it to change the quote that it is displaying each day at 9:00 a.m. plus send a push notification to the user at that time. I need the notification to go if the app is closed for the purpose of bringing the user to the app. The ListView can be updated when the user opens the app, they won't know the difference.
I am having problems with broadcast receiver and alarm manager.
I currently have my BroadcastReceiver as an inner class inside of my MainActivity. I did this in order to run the method that populates the ListView, which is in the MainActivity, from the BroadcastReceiver. However, I have my receiver registered and unregistered in the code, not in the manifest. This causes it to run each time the activity is created causing the ListView to populate each time as well defeating the purpose because I only need it to change and a notification to be sent each morning at 9:00 a.m.
I have tried making the broadcast receiver static and then registering it in the manifest but then I have all sorts of problems referencing non-static stuff from the static class. I have also tried making the receiver a separate class outside of the MainActivity class but then I can't call my method that populates the ListView inside the MainActivity from the receiver class. It seems like a no-win but I know that's not the case. It's currently registered in onCreate. I have tried onStart, onResume, etc... it works the same way. I just don't know what to do.
I don't have the push notification code in there yet I am still working on it.
Here is my code:
MainActivity (relevant portions):
Method to populate the ListView:
public void DailyQuoteDatabaseAccess(){
SQLiteOpenHelper sqLiteOpenHelper = new SQLiteAssetHelper(this,
DATABASE_NAME, null, DATABASE_VERSION);
SQLiteDatabase SqlDb = sqLiteOpenHelper.getReadableDatabase();
String rawQuery = "SELECT * FROM dailyQuoteTable ORDER BY RANDOM() LIMIT
1";
Cursor cursor = SqlDb.rawQuery(rawQuery, null);
DailyQuoteCursorAdapter DQCursorAdapter = new DailyQuoteCursorAdapter(this,
cursor);
this.mDailyQuoteListView.setAdapter(DQCursorAdapter);
}
Here I register the alarm dynamically in the MainActivity's onCreate method:
mTodaysQuoteReceiverStaticInnerClass = new
TodaysQuoteReceiverInnerStaticClass();
IntentFilter filter = new
IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
filter.addAction(Intent.ACTION_BOOT_COMPLETED);
this.registerReceiver(mTodaysQuoteReceiverStaticInnerClass, filter);
Here is my receiver class (which I made an inner class in the MainActivity):
public class TodaysQuoteReceiverInnerStaticClass extends BroadcastReceiver{
#Override
public void onReceive(final Context context, final Intent intent){
PopulateTodaysQuote();
}
}
Here is the method that sets my alarm. I call this method from the onCreateMethod in the MainActivity:
public void todaysQuoteAlarm(){
long currentTime = System.currentTimeMillis();
Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.HOUR_OF_DAY, 20);
calendar.set(Calendar.MINUTE, 9);
calendar.set(Calendar.SECOND, 0);
if (currentTime <= calendar.getTimeInMillis()) {
Intent myIntent = new Intent(this,
TodaysQuoteReceiverInnerStaticClass.class);
int ALARM1_ID = 10000;
PendingIntent pendingIntent = PendingIntent.getBroadcast(this,
ALARM1_ID, myIntent, PendingIntent.FLAG_UPDATE_CURRENT);
AlarmManager alarmManager = (AlarmManager)
this.getSystemService(Context.ALARM_SERVICE);
alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP,
calendar.getTimeInMillis(), AlarmManager.INTERVAL_DAY, pendingIntent);
}
else{
you can use broadcast receiver in the separate class and start a notification from there notification from broadcast receiver. I believe that you want to execute DailyQuoteDatabaseAccess() method when user will opens the application. I suggest you to maintain a separate table for today's quote and in the broadcast receiver update the today's quote table (assuming that you want change a quote once in a day) and fetch the data from Today's Quote Table to show the data in list view.
I have done an application that fire an alarm in certain time, and i am stuck on implementing remind me after half an hour functionality
what can i do to implement receiver, or service or anything that runs after half an hour of clicking the button of reming me after half an hour
any suggestions ?
Edited the code from Android execute a function after 1 hour to half an hour.
// the scheduler
protected FunctionEveryHalfHour scheduler;
// method to schedule your actions
private void scheduleEveryHalfHour(){
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0,
new Intent(WAKE_UP_AFTER_HALF_HOUR),
PendingIntent.FLAG_UPDATE_CURRENT);
// wake up time every 1 hour
Calendar wakeUpTime = Calendar.getInstance();
wakeUpTime.add(Calendar.SECOND, 30 * 60);
AlarmManager aMgr = (AlarmManager) getSystemService(ALARM_SERVICE);
aMgr.set(AlarmManager.RTC_WAKEUP,
wakeUpTime.getTimeInMillis(),
pendingIntent);
}
//put this in the creation of service or if service is running long operations put this in onStartCommand
scheduler = new FunctionEveryHalfHour();
registerReceiver(scheduler , new IntentFilter(WAKE_UP_AFTER_HALF_HOUR));
// broadcastreceiver to handle your work
class FunctionEveryHalfHour extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
// if phone is lock use PowerManager to acquire lock
// your code to handle operations every half hour...
// after that call again your method to schedule again
// if you have boolean if the user doesnt want to continue
// create a Preference or store it and retrieve it here like
boolean mContinue = getUserPreference(USER_CONTINUE_OR_NOT);//
if(mContinue){
scheduleEveryHalfHour();
}
}
}
You can write a simple service with a timer and whenever the time is up.it can do your thing.all you need to do is start a service with a timer inside of it
I have an android application where I am storing user's data on database when he/she activates the app. My app requires the user to stop the application manually in order to remove its entry from the database and along with that other services which keep running when the app is activated.
So I want to write a function which will be executed after every hour (when the app is activated) and will give a notification to user just to remind him/her about the service which is running .If the user had forgot to stop the service then they can stop it or continue with service.
What is the best efficient way of doing this. I dont want to drain too much of battery with thihs 1 hour basis check if the user considers it to run for a day or so. Please advice. Thanks :)
I suggest the code will be like this.
// the scheduler
protected FunctionEveryHour scheduler;
// method to schedule your actions
private void scheduleEveryOneHour(){
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0,
new Intent(WAKE_UP_AFTER_ONE_HOUR),
PendingIntent.FLAG_UPDATE_CURRENT);
// wake up time every 1 hour
Calendar wakeUpTime = Calendar.getInstance();
wakeUpTime.add(Calendar.SECOND, 60 * 60);
AlarmManager aMgr = (AlarmManager) getSystemService(ALARM_SERVICE);
aMgr.set(AlarmManager.RTC_WAKEUP,
wakeUpTime.getTimeInMillis(),
pendingIntent);
}
//put this in the creation of service or if service is running long operations put this in onStartCommand
scheduler = new FunctionEveryHour();
registerReceiver(scheduler , new IntentFilter(WAKE_UP_AFTER_ONE_HOUR));
// broadcastreceiver to handle your work
class FunctionEveryHour extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
// if phone is lock use PowerManager to acquire lock
// your code to handle operations every one hour...
// after that call again your method to schedule again
// if you have boolean if the user doesnt want to continue
// create a Preference or store it and retrieve it here like
boolean mContinue = getUserPreference(USER_CONTINUE_OR_NOT);//
if(mContinue){
scheduleEveryOneHour();
}
}
}
hope that helps :)
Use AlarmManager refer this and tutorial with PendingIntent
Try this way,hope this will help you to solve your problem.
new Timer().scheduleAtFixedRate(task, after, interval);
In my app, I use the AlarmManager class to set an alarm. To trigger the alarm after the mobile is rebooted I have used BroadcastReceiver. All works fine and my alarm is triggered at regular intervals. Now the problem arises in this case :
Suppose my current time is 2:30 pm and I set my alarm at 2:35 pm. After that, I switch off the mobile. After an hour when I switch on my mobile, no alarm is pop-up as the time on which the alarm is set. This is happening because the current time exceeds the time on which I set the alarm. To solve this issue what should I do. I have posted my code for setting alarm in the AlarmManager class. Please help me to solve this out
public class AlarmReceiver extends BroadcastReceiver {
#SuppressWarnings("static-access")
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals("android.intent.action.BOOT_COMPLETED")) {
Intent myIntent = new Intent(context, MyAlarmService.class);
PendingIntent pendingIntent = PendingIntent.getService(context, i, myIntent, i);
AlarmManager alarmManager = (AlarmManager)context.getSystemService(context.ALARM_SERVICE);
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.add(Calendar.MILLISECOND, (int) Utilities.diff(NoteManager.getSingletonObject().getAlarmTime(i)));
alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);
}
}
}
public static long diff(Date date) {
long difference = 0;
try {
// set current time
Calendar c = Calendar.getInstance();
difference = date.getTime() - c.getTimeInMillis();
if (difference < 0) {
// if difference is -1 - means alarm time is of previous time then current
// then firstly change it to +positive and subtract form 86400000 to get exact new time to play alarm
// 86400000-Total no of milliseconds of 24hr Day
difference = difference * -1;
difference = 86400000 - difference;
}
}
catch (Exception e) {
e.printStackTrace();
}
return difference;
}
In The Manifest File
<receiver android:name=".AlarmReciever">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
better way is to store that alarm details in database and retrieve it on boot via broadcast receiver as you are saying you implemented one. once notified remove the details from the database. this way u can track all your alarms. even you can start a Service on startup and do this operation
The Alarm app in the Android does the same, if your phone is switched off and there is Alarm to ring up, It will make your phone switch On , ring the alarm and go to sleep again.
Here is the link of source of Alarm app Git_Alarm app you can download it and see how it is doing this.
and if you are doing something else in your alarm reciever then to ring Alarm up. you can basically set alarmreciever again in the phone Boot up, here is the one answer which may help you Alarm problem if phone is switched off
Edit :- one link was broken, replaced it
I have set a AlarmManager which will give alarm repeatedly after certain time. I used following code for that.
Intent intent = new Intent(ViewDoughnut.this, NotificationMessage.class);
PendingIntent sender = PendingIntent.getBroadcast(ViewDoughnut.this, 0, intent,PendingIntent.FLAG_CANCEL_CURRENT);
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
am.setRepeating(AlarmManager.RTC_WAKEUP,nextAlarmTime, alarmInterval, sender);
Now to execute proper work at the alarm time I have created the following class extending BroadcastReceiver. Now I need the time in millisecond when the Alarm work should execute in that class. How to get it?
public class NotificationMessage extends BroadcastReceiver {
// Display an alert that we've received a message.
// #Override
public void onReceive(Context context, Intent intent) {
// here I need the time when the alarm should execute.
}
}
Here I like to add, system time is not working for me, because if the device is switch off at the alarm time, it execute that when the device is on after that time. But I need the time when it should execute.
You could create a class that derives from Application which holds all global variables. Then just set a long variable to hold the time before initialising the alarm