iOS5 has multi tasking enabled feature.
So, When the app is in background mode, can I download the data in background?
Will apple permit to write such code?
If yes, any examples will be of great help.
You can. You could use one of methods described in iPhone - Backgrounding to poll for events to get 'constat background' for you
But Apple is very unlikely to approve such abuse for AppStore
Related
I need to develop widgets for the iphone device. But don't know how to do it. Are they possible to develop & acceptable as per the apple norms?
Basically I need develop an app which can display its view also when the phone is locked or app is in Background mode.
I mean the app view will always on the top of the screen immaterial that the app is in active state or in background mode
Is this possible?
I am not sure about it so please guide me with the better option to achieve the same
Thanks & Regards,
Zahur
It's only possible for jailbroken devices. Apple has no public APIs that allow you to display things other than push/local alerts on the lock screen or home screen.
This is not possible using the iOS SDK. It may be possible on a jailbroken device, but there is a 0% chance that it would make it into the App Store.
Is this possible?
Nope
is there any API to enable background process...(in IPHONE SDK 4.1)?
Not in the conventional sense, no. Apple allow a restricted number of use cases, such as VoIP and music, but other background processes are not allowed. This is well documented on the iOS Developer Centre.
Is it possible to download a file while the app is in background in iPhone 4?
Yes, it is.
It's supported in ASIHTTPRequest as of v1.8:
http://allseeing-i.com/ASIHTTPRequest/How-to-use#background_downloads_ios
(There was also an experimental branch of v1.7 with it at http://github.com/pokeb/asi-http-request/commits/backgroundtask but this appears not to exist anymore.)
It's also supported in AFNetworking, see Does AFNetworking have backgrounding support?
Under iOS 4.x, you can use request some background time using UIApplication beginBackgroundTaskWithExpirationHandler: and perhaps continue a file download for a limited period of time.
See Apple's document on "multitasking" background execution for details.
I want to close other application running background with my app
how can i do it?
not possible
...unless your are programming in a jailbroken iPhone
You can request the user (who is in control of their device) to kill background apps manually and/or reboot their device. Which is not a good user experience, even though I've seen this request on some game app support forums/FAQs.
How can I alert a user that they need to do something without using a push notification? For instance, if I have an alarm clock app, how can I get it to ring when it is not already running without using a push notification?
You can't. As of writing, iPhone OS does not support background processes. (There wouldn't be any need for push notifications if iPhone OS supported background processes!) You can alert the user while your application is running using UIAlertView, but once your app is closed, you can't do anything.
As #Henrik P. Hessel mentions, it is rumoured that background processes will finally be supported in iPhone OS 4.0. Rumours also suggest that iPhone OS 4.0 will be previewed at the January 27 Apple Special Event. We'll soon see whether they're true...
That's not possible yet. There're rumors though that multitasking and background processes will be allowed in iPhone OS 4.0. But that's more than speculative.
You can't do it in the official iPhone OS 3.1.2 or lower. As mentioned by others, there are rumors that iPhone OS 4.0 will support background processes, but nothing about that has been confirmed by Apple.
You may, however, develop an application that can alert the user without push notifications if you forgo the officially sanctioned SDK + App Store route, and build applications for jailbreak (Cydia or Rock). There are a growing number of for-pay apps in jailbreak land these days. Of course, this will limit your app's exposure, and will be negatively looked at by Apple, but if you have a niche market (and don't mind requiring jailbreak users) or this is only for yourself/friends, this might be a good direction to go in.