I am developing an iPhone app which uses CoreLocation.
I'm having trouble finding out if the CoreLocation location continues to get updated when the app enters the background. I would like to have it stop updating, but I am not sure if I need to explicitly tell it to stop or not.
Could anyone shed some light on this?
You need to explicitly set whether your application will run in background mode. As documentation says Background Execution
Also you notice an icon in status bar will disappear when core location stops updating location data when your app. go to background mode
Kindly check the following url .. hope it is useful to you
http://numiko.com/labs/?p=238
As with most things, programming related; if you want an action to occur, you almost always need to tell it to do that thing, or an ancillary thing which side effects that.
If you want it to stop updating, tell it to do so. (And yes, there are two different modes that will collect location info in the background. One is only on the iPhone 4 though.)
Related
I'm developing an iPhone/iPad application through Phonegap, is there a way to implement a sort of "click here to quit app"? I mean quit for real, not "put it in the background and go to home screen".
Thanks in advance.
you can use following code to quite your app on click,
device.exitApp()
OR
navigator.app.exitApp()
Hope this may help you.
is there a way to implement a sort of "click here to quit app"?'
Yes, there is a way for really exiting the app and killing its process.
But never do that. Not only because Apple rejects your app if you do this. The problem with this is bad user experience. iOS is not a desktop operating system. You have a Home button for leaving apps (and again, there's a reason apps don't exit completely).
The window size is, conceptually, not spacious enough for maintaining an extraneous 44x44 pixel frame (44 pixel is the minimal size that can comfortably be touched, according to Apple's Human Interface Guidelines) dedicated only for exiting.
However, if you still want to exit after this lecture, there are several ways:
exit(0);
pthread_kill(pthread_self()); // on the main thread
[[UIApplication sharedApplication] terminateWithSuccess];
etc. Some of them may have a binding in PhoneGap (if not, it's easy enough to write one yourself).
You should not do that as this may considered as violation of iOS Human Interface Guidelines, lead rejection of your app.
Always Be Prepared to Stop
**Save the current state when stopping at the finest level of detail possible so that people don’t
lose their context when they start the app again.** For example, if your app displays scrolling data,
save the current scroll position. To learn more about efficient ways to preserve and restore your
app’s state, see “State Preservation and Restoration”.
Apple guidlines link :
http://developer.apple.com/library/ios/#documentation/userexperience/conceptual/mobilehig/UEBestPractices/UEBestPractices.html
in the application's plist put
UIApplicationExitsOnSuspend = TRUE
and when the user hits the home button, the application will quit. No need for a button, no need for exit().
http://developer.apple.com/library/ios/#documentation/general/Reference/InfoPlistKeyReference/Articles/iPhoneOSKeys.html#//apple_ref/doc/uid/TP40009252-SW23
Im trying to simulate a touch on as UIWebView, how can I programmatically fire a touch event at a certain location? (x and y coordinates)
Just call touchesBegan?
Ideally I'd like to do it without any javascript hack because in the future it may not be a uiwebview
It's not easy to synthesize a touch event on the iPhone: you have to use undisclosed API, so you have a high probability of breaking on every update of the iOS and getting rejecting from Apple.
Here's a link that demonstrates how to synthesize a touch event on the iPhone:
Here's another question on StackOverflow: How to send a touch event to iPhone OS?
It's worth pointing out the KIF framework here. It's intended to run in the simulator but part of the code is simulating touch evens in code. with luck, this will be a good starting point.
https://github.com/square/KIF
Specifically, look at stepToTapViewWithAccessibilityLabel in KIFTestStep.m and the line
[view tapAtPoint:tappablePointInElement];
What you need to do is first create the events you want, and then send them to SpringBoard over the "purple port" eg. mach port. To make them system wide you must forward them to each application over the port. That means you need to actually do what the windowmanager does and looking at which app is active, screen locked, etc.
There are a hand full of private framework APIs that work (IOSurface, GraphicServices, SpringBoardServices, etc.) to get you the pieces you need.
You will have to load these private frameworks at runtime using something like dlopen().
This is 100% possible without jailbreak as of iOS 6.1.4 (current ATM), but you will be loading private frameworks which is not allowed by apple for AppStore ;)
It is possible. Exactly how you mentioned, using GSEvents and sending them to the purple named port of the aplication you are trying to control/simulate. Of course you need KennyTM's GSEvent.h to accomplish this.
I've done this for iOS 4.3, just by changing some of the values that Kenny had (like kGSHandInfoTypeTouchDown), but now I'm trying to do it for iOS 5 and it's not working, till now.
EDIT: It is now working for iOS 5.1.
Without jailbreaking there is no real way to hook a gesture recognizer into all views of the entire system. First off, your app running in the background doesn't have the ability of executing this code.
I have an app where I have 5 sets of animations that I'm storing in an array. The animations get picked to play randomly after a button touch. This is all working perfectly, however I noticed a bug when I quit the app and reopen immediately, I'll see my main view, then it'll jump to my second view that has the animation in it. (This shouldn't happen since you have to tap the main view in order for it to modally swap in the second view. If I interact with it everything works for a few seconds, then it closes with no crash log.
I finally realized that some of the objects must not be getting released fast enough, since if I close the app and wait three seconds, then reopen, everything executes fine.
I didn't want to put down code to show as this is more of a brainstorming question. I'd love any insight that could point me the right way. I changed a lot of my code to get rid of convenience methods and have all my variables defined and then released in my dealloc.
Is there a way to truly tell the app to kill everything on quit? It's not set to run in the background so this is a bit odd. Thanks for your help I'm still new to this and learning!
Alright, after working on this all weekend and doing more research comparing a barebones version of my app to my prerelease version, I traced memory leaks to the Flurry Analytics api that I am using. Apparently I was suffering from the same issue as the post here: App hangs on restart with latest Flurry SDK and ios4 . I resolved this by setting these optional methods to false, since they take extra time to send data after the app terminates, and depending on the connection it takes a few seconds.
FlurryAnalytics.h
/*
optional session settings that can be changed after start session
*/
+ (void)setSessionReportsOnCloseEnabled:(BOOL)sendSessionReportsOnClose; // default is YES
+ (void)setSessionReportsOnPauseEnabled:(BOOL)setSessionReportsOnPauseEnabled; // default is YES
Hope this helps anyone else who experienced something similar to me!
All apps can enter the background by default. Normally they do not do anything there, but they stay there in a frozen state and when you open them again, your program does not restart, it just picks up where it left off.
Anything that's set as an animation delegate might not get released, since it's retained for that purpose until the animation completes.
You can add an applicationDidEnterBackground: method to your app delegate to get informed when your app is going into the background, but exactly what you need to do depends on the design of your app. You can also add applicationWillEnterForeground: to do anything you need to do differently when restarting, as opposed to newly starting.
You might be able to force your animations to complete by starting a new animation with duration 0.0 (or very short if for some reason you can't do that).
If this happens only if your app goes to bkgnd and comes back AND you don't mind if the app restarts everytime it comes back then just put UIApplicationExitsOnSuspend in your app's plist. In all my cases where these and other bad things happen with apps going to and returning from bkgnd this helped.
While you might still see the app on the buttom when double tapping it is really stopped and will restart. Apps that show on the buttom do not always have to run or be stored in the bkgnd I learned.
ps. don't forget to set the value of UIApplicationExitsOnSuspend to YES
My app runs significant location change updates in the background. However the GPS display icon never turns off..even when app is in the background. Is there a way to use location manager with Significant location change in the background and have the GPS icon NOT display continuously? My users don't understand that it is only periodically obtaining location coordinates and instead think its constantly running in background and thus deleting app thinking its too power intensive. Please help.
I believe that any use of CoreLocation will prompt the location arrow. That includes any of the geofencing CLRegion use, -startMonitoringForSignificantLocationChanges, and -startMonitoringForLocation. I think that is Apple's safeguard that something is using your GPS, even in limited use.
That arrow will be visible till you unregister your application from significant change. But I faced problem, what I can't fine point where I can do this. In my case will be best to unregister on application kill, but with multitasking there is no such ability to handle this moment to unregister.
So I׳m trying to play some effects in my Cocos2D game using SimpleAudioEngine , but after I have added them my app crashes when it goes to background (multitasked).
I searched for this problem in the internet but all the solutions that I found didn't work for me. What I did find out is that this problem happens because my app is somehow trying to play sounds when backgrounded.
In console it shows me (which is the same error I found other people had):
sgx error (background gpu access not permitted):
And another thing, when I run my app on the simulator, or even on my device while debugging carefully (going line-by-line with XCode while the app is running) this doesn't happen.
I just had this issue. I resolved it by having a bool to check if the app is running or in background that I set to true when the app goes to foreground ( applicationWillEnterForeground ) and that I set to false when the app goes to background ( applicationDidEnterbackground ) . So using the bool you can tell if the app is in the background and if it is, I just exit out of drawView function in EAGLView (thus not doing any graphics rendering which was causing the error).
I am a very dodge programmer but that method has worked for me and I hope it works for someone else. I did not need to unload and reload my sounds or anything and my app now has Multitasking XD
I was experiencing this, on about 25% of the occasions that my application re-entered the foreground. Like you, when I removed the sounds, the problem went away. That is how I came across your question here.
I may have found a solution to this. I have made what appears to be an unrelated change, but the problem seems to have gone away. Now, when my app enters the background, I invalidate my main scheduled timer. When my app re-enters the foreground, I then re-schedule the timer (after reloading my sounds, which I completely shut down on entering background).
So far, the problem has not come back. I would be interested to know if this helps.
I just resolved this issue on my end. Here's what was wrong in my case and, from what I can tell from the other answers and comments on this page, many other people's case as well:
By default, when I started my project, CCDirector::sharedDirector()->pause(); and CCDirector::sharedDirector()->resume(); were both being called twice, once by (void)applicationWillResignActive:(UIApplication *) and (void)applicationDidBecomeActive:(UIApplication *) respectively in AppController.mm, and once by AppDelegate::applicationDidEnterBackground() and AppDelegate::applicationWillEnterForeground() respectively in AppDelegate.cpp.
Make absolutely sure that these methods are only being called once, in AppController.mm. In AppDelegate.cpp, instead make sure that you are calling CCDirector::sharedDirector()->stopAnimation(); in place of CCDirector::sharedDirector()->pause(); and CCDirector::sharedDirector()->startAnimation(); in place of CCDirector::sharedDirector()->resume();.
Hope that's helpful to anyone else stuck in this crappy situation!
Are you sure it's related to audio? "background gpu access" sounds like it's using OpenGL.
I had the same issue in my application and spent some 4 hours to find out. Going background was OK the first time, but crash application the second time. With a short error message related to OpenGL. I had the same questions: how audio can crash graphics. But it wasn't a question of audio, but a question of notifications...
I discovered that going foreground was creating 2 timers in my custom level meter class.
I had registered UIApplicationWillEnterForegroundNotification and UIApplicationWillResignActiveNotification. Then, going background invalidated only one, since I registered only on notification... That was it!
One need's count its notifications!