My App relay heavily on server data, when i have no connection to my server i cant present any data. so i present to the user a screen explaining him the no connection situation and give him a button to exit the application
my question is: will it pass Appstore tests? i never tried it before and i know they dont like apps to use exit(0), i was also was suggested to put a screen with no buttons and block the user from going back to other app screens and put a message on this screen and make the user to click on the home button in order not to use exit(0)
is that allowed?
No, you must not call exit. Your app will be rejected. This has been repeatedly discouraged by Apple and is known to cause serious bugs with iOS multitask switching. You should simply leave the user to use the home button themselves.
Do not call the exit function. Applications calling exit will appear to the user to have crashed, rather than performing a graceful termination and animating back to the Home screen.
http://developer.apple.com/library/ios/#qa/qa1561/_index.html
Related
We don't want the user enter our app if the app is out-dated.
Is that is possible to quit a iOS app when we do some date check BEFORE the app launch?
Or it is possible to quit the application after the main view is loaded?
Before the app launches: no. The launch animation is already in progress when the OS calls main.
After some time (1-2 sec): yes. You can use one of
[[UIApplication sharedApplication] terminateWithSuccess];
exit(0);
abort();
assert(0);
pthread_kill(pthread_self());
so many ways, but neither will go through AppStpre - you're not supposed to close your app programmatically. You're supposed to notify the user via an UIAlertView about the outdated app and disable interaction with the app.
According to Apple you cannot exit(quit) your application through code. i.e if you use exit(0). Your application will be rejected for that. Although you can use exit(1) and delay the exit time of your application. Or you may like to use local notification which is quite handy.
Don’t Quit Programmatically
Never quit an iOS application programmatically because people tend to
interpret this as a crash. However, if external circumstances prevent
your application from functioning as intended, you need to tell your
users about the situation and explain what they can do about it.
Depending on how severe the application malfunction is, you have two
choices.
Display an attractive screen that describes the problem and suggests a
correction. A screen provides feedback that reassures users that
there’s nothing wrong with your application. It puts users in control,
letting them decide whether they want to take corrective action and
continue using your application or press the Home button and open a
different application
If only some of your application's features are not working, display
either a screen or an alert when people activate the feature. Display
the alert only when people try to access the feature that isn’t
functioning.
Source
I want to send my Application to background simply clicking on Button inside my Application.
Is there any way to call applicationdidenterbackground manually or any other way ?
iOS Human Interface Guidelines says "Don't Quit Programmatically", whereby quitting must be understood as including "suspending":
Never quit an iOS application programmatically because people tend to interpret this as a crash. However, if external circumstances prevent your application from functioning as intended, you need to tell your users about the situation and explain what they can do about it. Depending on how severe the application malfunction is, you have two choices.
Display an attractive screen that describes the problem and suggests a correction. A screen provides feedback that reassures users that there’s nothing wrong with your application. It puts users in control, letting them decide whether they want to take corrective action and continue using your application or press the Home button and open a different application
If only some of your application's features are not working, display either a screen or an alert when people activate the feature. Display the alert only when people try to access the feature that isn’t functioning.
If you really want to exit your app programmatically, then you can call exit(0);, but I doubt that you app will pass the Apple review.
Unfortunately There is no any officialy way to force app to background state(Pause state).
So here is the issue I am facing. Certain portions of the application I am building open some c network sockets that allow connections to various servers/services. However, if the application goes to sleep, these socket connections are lost, and error out when trying to reload them. So what I want to do is basically notify the user when the app launches again, that the application needs to be restarted. The main question is, can I present them with a button that will kill the app by using exit(0) without my app getting rejected?
Apple says that the user should be in control of when the app is killed, and in this case I see that they are, but I am not sure of Apple's opinion on this. Has anyone else used this? Have you been rejected for this? Thanks in advance for any advice!
EDIT:
Thank you everyone for your advice. I am trying to take everything into consideration, but because the app needs to be submitted ASAP, I just need to know, if we can not get another solution, if the above proposed solution, will get rejected or not.
Your application delegate receives notifications when significant events affect the life of the application. Rather than ask your user to recreate a session, you should attempt to discontinue network operations and then resume them at the appropriate times in the application's lifecycle automatically.
You can gracefully kill network sockets (amongst other things) in any number of places as the application prepares to exit or enter the background via callbacks in your application delegate:
applicationWillResignActive:
applicationWillEnterBackground:
applicationWillTerminate:
Potentially reconstruct sockets in:
applicationDidBecomeActive
applicationWillEnterForeground
Have you tried not allowing the app to run in the background? Then it will be killed whenever the user exits to the home screen. This might be a bit aggressive, but would solve the problem. From Apple's opting out of background execution:
"If you do not want your application to remain in the background when
it is quit, you can explicitly opt out of the background execution
model by adding the UIApplicationExitsOnSuspend key to your
application’s Info.plist file and setting its value to YES.
When an application opts out, it cycles between the not running,
inactive, and active states and never enters the background or
suspended states.
When the user taps the Home button to quit the application, the
applicationWillTerminate: method of the application delegate is called
and the application has approximately five seconds to clean up and
exit before it is terminated and moved back to the not running state."
See also: How to prevent my app from running in the background on the iPhone
The documentation is pretty explicit about this, "There is no API provided for gracefully terminating an iOS application." See Technical Q&A QA1561
How do I programmatically quit my iOS application?.
To be blunt, terminating an app to cleanup a socket is just like dealing with memory management by forcing an app to exit instead of calling release.
What about bringing up a modal view controller telling the user to quit the application? You could make this view controller without any dismiss button, so the user is obligated to kill the app.
I would like to close an iPad application as a result of clicking on a UIButton. However, I have not seen how to do this in the Apple documentation.
What call needs to be made to close an app?
Thanks.
You can call exit(0) to terminate the app. But Apple don't like this as this gives the user a feeling of sudden crash. If you still want to have an exit function (with a potential risk of rejection) then you should also send your app delegate the applicationWillTerminate message (if you have anything important there) before performing the exit.
It says:
Don’t Quit Programmatically
Never quit an iOS app programmatically because people tend to
interpret this as a crash. However, if external circumstances prevent
your app from functioning as intended, you need to tell your users
about the situation and explain what they can do about it. Depending
on how severe the app malfunction is, you have two choices.
Display an attractive screen that describes the problem and suggests a
correction. A screen provides feedback that reassures users that
there’s nothing wrong with your app. It puts users in control, letting
them decide whether they want to take corrective action and continue
using your app or press the Home button and open a different app
If only some of your app's features are unavailable, display either a
screen or an alert when people use the feature. Display the alert only
when people try to access the feature that isn’t functioning.
The only way for a user to exit an application is by pressing the Home button. You can't do it in your app, at least not in a way that Apple would accept.
You can try to use command:
exit(0);
I am fairly new to iphone app development. I am creating an app that has multiple views. Initially it starts with a view for authentication and then load views according to user interaction. When I build and run the app - the first time it shows the "Default.png" screen and then shows the first view where I do my authentication process (typing in userid,password and do a web service) and then after the credentials are verified it takes me to the next view. When I close the app at this state in the simulator and reopen it again, I am seeing the same state in which I closed my app. But here is what I want. When I relaunch the app I should be able to show the "DEfault.png" and screen and then show my initial authentication view. Can you please help me out on this ? Thanks
It sounds like the problem you are trying to solve is that your authenticated session may time out while the app is suspended and you need to log in again.
Although the proposed solution (setting UIApplicationExistsOnSuspend to true) would work I think you should consider a different approach.
Apple recommends that you do everything you can to make it look like the phone supports multitasking. That is why, by default, your app will suspend and resume instead of exit and relaunch. In your case, though, you may need to re-login to resume the session. I offer you a couple of alternate solutions:
Cache the credentials (ie username and password) and silently use them to resume the session when needed. If the back-end supports this.
Detect when the session has become stale and bring in a view to inform the user that the session has expired and ask them to log in again. This would also address the issue if the user keeps the app active past the timeout of the session.
Both of these approaches should improve perceived app performance and integrate better into the Apple usability guidelines.
That's because iOS 4 apps are supposed to support multitasking. You can change the app so it doesn't: In Info.plist, set UIApplicationExitsOnSuspend to true (i.e. <key> UIApplicationExitsOnSuspend</key><true/>) — make sure it's a boolean and not a string. Note that this will probably make startup slower, since the app has to be launched again.
The other way is to handle applicationDidEnterBackground: in your app delegate and do two things:
Reset your view hierarchy (you can do this on next launch, but doing it earlier might help to free more memory)
Show "Default.png" in a full-screen view — iOS takes a screenshot of your app after it's hidden which it uses to animate the app back in.