how to delay application quit time in iphone sdk? - objective-c

I want to register my app for push notification when my application terminates so i think if i delay my app quitting time it could be possible.Does someone knows how to delay application quitting time? I think this method
[self performSelector:(SEL)aSelector onThread:(NSThread *)thr withObject:(id)arg waitUntilDone:(BOOL)wait];
will do my job but i don't know how to use this method if someone knows please tell.I need to send some data to a server along with registering for Push Notification when my app quits.

I can't imagine why you would want to do this. If it were even possible it would be extremely annoying for a user to tap the home button and the app to take x amount of time to shut down. This time 'x' being dependent on the server connection creates even more user headache.
Apple have the home button exit apps immediately for a reason.
If you want to register the Push Notifications like you suggest, do it while the app is running. If your worrying that they won't be properly set if the user exits prematurely... don't.
As users, we all know there are sometimes consequences of exiting a program without giving it time to save your settings.

For push notification it is better to register when the app first starts and then send the push token to your server in the background. However, if you have a good reason why you need to do the registration just as the app terminates, I believe you can do this if you are using iOS 4. iOS 4 has a new feature called "task finishing" that allows an app to stay running for a few minutes after the user closes it so that it may finish up any tasks it was in the middle of (such as saving data).

Related

Expo/React Native : A Continuous Alarm or Sound Notification (like receiving a call ) triggered by remote server

I am using Expo to build an app that will pop up a notification with custom sound and vibration when triggered remotely. The alarm/vibration would play until its dismissed by the user or it times out (say after 1-2 mins) .
Example use case would be when a partner needs my immediate help with baby, they can press a button the app and that would send signal to backend server which would then trigger the notification with alarm on the app at the other end. When the notification is dismissed, an acknowledgement message is sent with Yes or No type message. If the notification times out, then another message is sent like "no response".
Key point to note is that when the app is fully closed, the notification should still be able to pop up.
From my limited understanding , expo notification or push notifications in general cannot achieve this as they don't allow us to create notifications that directly open the app. Even a solution which works like phone or video calling apps (which open when someone calls you ) could work.
Any help would be much appreciated.
Many Thanks!
I looked up expo push notifications but they are limited in terms of customising the notifications.

RemoteNotification TOKEN not received if push notifications are not allowed

Really confused with this one!
I have an Adobe AIR iOS app and I am using the RemoteNotifier to subscribe for PushNotifications. More details http://www.adobe.com/devnet/air/articles/ios-push-notifications.html
I have the following listeners.
remoteNotifier.addEventListener(RemoteNotificationEvent.TOKEN, onToken);
After I reset my iPod to factory settings and reinstall my app (using the adhoc distribution), I click "Don't allow" for the pushnotifications when I get prompted.
I find that I then don't receive any RemoteNotificationEvent.TOKEN, so my app basically hangs waiting for that.
If I go to my Settings, Notifications and have a play with
Toggle Alert Style from the None to Alerts AND
Then back to None again (as it was)
I find that I can go back and launch my app with not problems. It's just that on the very first time user flow, I don't seem to get any TOKEN back.
Any ideas? Has anybody else seen this behaviour?
Or knows how I should handle this?
Thanks!
Hopefully I am correct, someone please correct me if I'm wrong.
From what I am able to find out, you won't get a RemoteNotificationEvent.TOKEN when the user clicks on "Don't Allow".
For some reasons that I am still unclear about, how after you play with the Settings and relaunch the app, you get the RemoteNotificationEvent.TOKEN, regardless of the notification settings you have set. But maybe that's the way it's meant to be?
So, really I have to change the flow such that I don't wait on that RemoteNotificationEvent.TOKEN before loading my first screen. If the TOKEN comes back, it comes back, otherwise if it doesn't, it's not a big deal as that means the user clicked on "Don't allow" and we don't need to send PUSH notifications anyway.
Everytime I relaunch my app, I do make the call to subscribe and get the TOKEN though, such that if the user was to enable the Notifications in the phone's Settings, I do have a TOKEN ID to send the push notification too.
The only problem I see with this though, is that should the user change the Notification to ON via the phone Settings and doesn't relaunch the app (to retrieve the TOKEN) then the device doesn't get push notifications.
Not sure how to handle this?

gpus_ReturnNotPermittedKillClient while app is being "backgrounded"

I have an (old) audio app that is misbehaving on iOS 5.1.1. It records audio and on older iOS versions (don't know precisely where the "break" is) it would stay "in foreground" while recording, without any nudging.
But on 5.1.1 the app is put into background after two minutes, and then things go sour. Currently (will have to change this, I suppose) the app kills recording when it's backgrounded (and it appears to do this successfully), but it still dies with a trap in the above routine.
Unfortunately, the call stack is empty when this occurs, so there's little clue as to why the app's getting killed, but I gather (just from hints here and there on the web) that the trap occurs because a background app cannot use any UI facilities, and the app must somehow be calling something UI-ish. But I haven't a clue what it might be.
I've worked through most of the notifications, to see if a notification might be lurking in a queue somewhere and doing something, but I've not found anything so far that might be triggering a UI opp.
Any ideas on how to track this down?
Aha!! The app uses an Apple freebee widget known as AQLevelMeter. When recording is stopped, the level meter is also stopped, but the stop code inside AQLevelMeter.mm does not invalidate the timer that's driving the UI updates.

Long-running task performed in foreground is suspended when app enters background

When a user first opens my app, I need to download and install some content from a server before they can begin using the app. The problem is that this takes around 5 minutes on wifi, during which time the app goes into the background and the download is suspended.
Is there any way to either:
prevent an iOS app from entering the background whilst I perform my download
or continue peforming the task in the background (i.e. perform the task irrespective of whether the app is in the foreground or background)
Thanks
It really doesn't matter, if the user presses the home button it will go to background. Although you can do two things to mitigate the problem:
Use beginBackgroundTaskWithExpirationHandler, to give you a bit more time to download. Which you can read here.
Don't allow the device to become iddle, with [UIApplication sharedApplication].idleTimerDisabled = YES;. You can read more about that here.
Either way, the best thing you can do is to tell the user, that is an important download and he shouldn't quit the application.
Can't you include some or all of the content in your app bundle instead, and just download changes on first run?
I can't imagine this is a good first user experience, and it may not pass App Store review like this.
The only third party apps that are allowed to download in the background are newsstand apps loading issue content, and Apple are pretty strict about what they allow as newsstand apps.
You can't do what you want, in this situation. One way, and I think the best and only, is to resume your download when you app becomes active (returns to foreground state). Also, don't forget to register for connectivity notifications (Reachability class can be used for this purpose from this Apple sample app http://developer.apple.com/library/ios/#samplecode/Reachability/Introduction/Intro.html). Good Luck!

canceling API request while application entering into background

While launching the application in my iPhone, I need to download the data from the server. While downloading data(in middle of process) if I press home button to enter the application into background.this time I need to stop the API request which is already executing. currently applicationDidEnterBackground method is calling with delay(after downloading data). In the mean time application is crashing. how can we cancel the URL connection while application is entering to background.
Please help me out.
Thanks in advance.
One way to do it is to set some kind of flag in your app controller that you can periodically check to see if the request is cancelled.
Or, even better, the NSThread object provides a mechanism to indicate that it should be cancelled. If you go into the background, set your detached thread to cancel (via [NSThread cancel]) and then in whatever API callsback you have, you should periodically check to see if [NSThread isCancelled] is returning YES.
Here's a link to Apple's documentation on [NSThread cancel].
http://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSThread_Class/Reference/Reference.html#//apple_ref/occ/instm/NSThread/cancel
hope this helps!