I've a really strange behavior of my iOS app. It prevents the device from going to standby. I've already searched if there is anywhere the idleTimeDisabled flag set, but this isn't the case. The idle timer inside the settings app is set to 2 minutes and works within other apps. The device isn't jailbroken and the even restarting the device didn't help. The app was written by somebody else and I'm new to it. So in the moment I don't have any idea what to look for. Has anybody of you an idea, why this could be the case or how I could figure out what's the reason for this behavior?
Thank you very much!
If your app is using AVPlayer or some other similar AVFoundation functionality, this can be the cause.
If AVPlayer is playing a video, a device will not go to sleep while a video is playing.
If the video is playing in a loop, the device will never go to sleep.
Edit:
With iOS 12 this is now possible by setting
player.preventsDisplaySleepDuringVideoPlayback = false
Put this line in your ViewController that require not being in sleep mode
[[UIApplication sharedApplication] setIdleTimerDisabled:YES];
Important: You should set this property only if necessary and should be sure to reset it to NO when the need no longer exists. Most
applications should let the system turn off the screen when the idle
timer elapses. This includes audio applications. With appropriate use
of Audio Session Services, playback and recording proceed
uninterrupted when the screen turns off. The only applications that
should disable the idle timer are mapping applications, games, or
similar programs with sporadic user interaction.
Make sure you are not "testing" with your Xcode. Because it will always remained as turn on status as long as you plugin your iPhone with a cable.
Related
I'm currently working on an app which reminds the user, when he gets to an certain location. I want this app working in background as well and searched for solutions.
In the AppStore i found the App called Sleep Cycle, which tracks your activities during your sleep. When you set the alarm, and running the App in the Background you get this screen red bar on the top of the Display of your iPhone.
http://i.stack.imgur.com/uEejp.jpg
Does anybody know what kind of Backgroundmode this is, and how i can transfer it to my app?
Thanks
To have such a red bar I use audio background mode and also I record sound in background. Since Sleep Cycle asks user to allow access to microphone I believe it also records audio in background
We've been using the AIR sound API, building for iOS, with no problems till now, the problem is that the sound works until iPad goes to sleep and there's no sound from our app when iPad is woken back up.
Note: we have the app set to exit on suspend, and we don't have this problem when user suspends -- i.e, hits the button and goes back to desktop.
We only have it when iPad goes to sleep (screen goes dark but app is still running). As far as I can tell our app is not receiving any events from iOS when the iPad goes to sleep or wakes back up. Once this has all happened and the game has no sound, but exiting and restarting makes it work again.
We are getting an activate event from the native application object when iPad is woken up, I'm also checking (just because it sounds useful) the value of SoundMixer.areSoundsInaccessible, but that's way off base. I do get a soundchannel object back when I play a sound while the problem is in effect, I just can't hear it.
We were having a similar problem with audio not playing (roughly half the time the device had been asleep), and fixed it with this:
// AudioPlaybackMode.MEDIA is the default value
SoundMixer.audioPlaybackMode = AudioPlaybackMode.AMBIENT;
Once that was done, audio came back immediately after the app woke up.
Note that AMBIENT's behaviour depends on whether the microphone is being used.
I have developed a small music app by using AVPlayer and MPMediaPickerControlLibrary with all the normal required functionalities for a music app. The app is also capable of running in the background when the screen is locked.
Now, what I want is to start the app when the screen is locked through a shake and soon as the app starts the current song should start playing.
I am not able to achieve this from a long time
Any suggestions on this will be highly appreciated or any other workaround apart from shake to turn on the music in the app when the screen is locked in iPhone.
Thanks in advance.
You need to implement the a CMMotionManager object, but keeping it running all the time in background will be a major power consumption issue.
Modifying the updateInterval property to reduce the number of updates will defeat the purpose, given that you may miss a shake in background.
Now, if the app was terminated by the user, then no motionManager object will be available until the user launches the app again.
In android if you hold a partial wake lock, the CPU will continue to run, regardless of any display timeouts or the state of the screen and even after the user presses the power button. In all other wake locks, the CPU will run, but the user can still put the device to sleep using the power button. Is there any such mechanism in iOS like this? For CPU will continue to run and detecting the gestures and Sensors while device is in lock screen.
No. This is deliberately not available and hidden by Apple to conserve battery life. The only background modes to allow this, where your app is basically always executing in the background and the device does not go to sleep (but screen can be off), are VOIP and location services. To prevent abuse of these background modes, Apple reviewers are much harder on apps that specify these modes in their plist file, to make sure the apps really require these modes.
If you intend to make an enterprise app, which will not go to the app store, you can of course use these modes, as well as private API, to achieve what you wish.
For what its worth,
when device camera is on preview, screen wont go to sleep.
maybe a usable WAKELOCK-like option for immediate use.
If anyone is still searching, I found a way to prevent the app from going to sleep by setting the isIdleTimerDisabled to true. It turns off the timer that detects the time when the phone should go to sleep.
UIApplication.shared.isIdleTimerDisabled = true
Now if you want to turn it off at a specific time point you could also try to use a timer to set it to false again. For example if you want to turn it off after 3 minutes, you could do something like that:
let _ = Timer.scheduledTimer(withTimeInterval: 180, repeats: false) { (Timer) in
UIApplication.shared.isIdleTimerDisabled = false
}
I am creating player application, which is playing audio streams through internet. I want to add alarm functionality in my app - in particular time my player begins to play audio stream, I am trying to use UILocalNotification mechanism. But I've difficulties with it when my application in background mode, I can't call 'play' method, when notification is receiced (can't without user interaction). May be it is impossible?
But I bought this application:
http://itunes.apple.com/us/app/radio-alarm-clock-mp3-radio/id380271167?mt=8
And it seems like radio can start playing when local notification is received. Alarm can start playing radio when my app is in background mode.
Earlier I was trying to use NSTimer for this, but when my app goes to background, timer stops. If I use beginBackgroundTaskWithExpirationHandler: it works only 10 minutes. My app has special flag in plist, what is is audio application, and can playing music in background. In this case timers are working. But if I stop playing and go to background, timer is not working.
When I use \Radio Alarm Clock' application, I hear 'white noise' from dinamic, when music in not playing. May be it is the secret of this application?
Can you help me with my problem? Thanks.
maybe it's too late.
I had a look to the app you've mentioned at http://itunes.apple.com/us/app/radio-alarm-clock-mp3-radio/id380271167?mt=8 and yes, I think you are absolutely right, the only way to achieve that the application remains active while in background is to play a fake sound while it is in the background, which should be prohibited by Apple.
I've also seen that they don't use the remote iPod control, and this was strange at a first look.
At the end my opinion is that they do the following:
Avoid the call to beginReceivingRemoteControlEvents which allows to activate the iPod controls while in background (in fact they don't have it)
In this way, the status bar doesn't show the play icon while
the app plays audio
When the app goes in background, it probably plays a no sound periodically (once every 10 secs for example), in this way the app remains active
I saw that they also avoided to manage interruptions, for example in case another app is in foreground and plays music. Again Apple should have rejected the app for that reason, cos it is against the rules to follow while in background, but maybe they didn't see it during the acceptance tests.
So my interpretation is that they have intentionally missed to activate the iPod controls, just to avoid to show the play icon in the status bar while in background. In this way, the users are unaware that the app is active and is doing something strange after they close it.
In addition you can see that the app doesn't interrupt when another app plays in foreground a sound or audio, because otherwise they risk that the app doesn't restart on time when the alarm shpould fire.
That's just my idea of how they do that, and I think this is the only way for an audio app on iOS to remain active while it is in background and is supposed to be halted (well, in case Apple doesn't see the trick).
Have you tried adding this to appdelegate.m
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {
// Call your method in here.
}
if you have can you add code for us to see what your doing.