My iPhone application has two states: UI and Game.
Game is played using device tilting only so I switched auto-sleep off on game start:
[[UIApplication sharedApplication].idleTimerDisabled = TRUE;
But as soon as I return to UI, I want auto-sleep to be active again. So on game finish I restore it:
[[UIApplication sharedApplication].idleTimerDisabled = FALSE;
After a long game playing, it resulted in immediate darkening of the first UI screen that I go after the game.
So it seems that when idle timer was disabled it was still calculating time. And it had fired immediately after "enabling". How can I fix this problem?
I don't know if the idleTimer can be reset programmatically, but an option is to require the user to touch the screen before it goes back.
Another option is set your own timeout once you are back and wait for it to complete before you set idleTimerDisabled = NO. Remember to clear this timeout if you start the game again.
This answer may be usefull.
I also had problems when using Music/Audio players, which seemed to reactivate the timer.
ps: in ObjectiveC you should use YES/NO instead of FALSE/TRUE
Related
I am writing a music player that I am trying to allow to go to sleep mode. The problem is, every second, the ui is updated and I think that is preventing the phone from sleep. I added this line:
[UIApplication sharedApplication].idleTimerDisabled = NO;
and it did nothing. I have seen other apps that go to sleep mode even if the ui is being updated. How can I accomplish this?
Based on the comments, Are you running your app while attached to Xcode? By default Xcode stops the device going to sleep. If so, just disconnect and run, it should go to sleep (provided your devices sleep timer is not too much)
I'm trying to build an alarm app that can fire an alarm while in locked-screen mode (the app is in the foreground, but the screen is locked). The alarm has to be triggered by a NSTimer not by uilocalnotification.
In iOS 4 I used the 'play silent sound every 10 seconds' hack to prevent the app from going to deep sleep and the timer events worked fine. However, in iOS 5 this doesn't seem to work.
Any ideas? Or this should work and I'm doing something wrong?
It seems that you actually can use the 'play silent audio' hack in iOS 5, but the audio has to be audible meaning you can't play it at volume set to 0.0.
You can use github.com/marcop/iPhoneInsomnia and set the volume to greater than 0, but it still doesn't work because the sound file is so short that the system kills your application before the timer is triggered and replays the sound. I solved this by setting the numberOfLoops of the audioPlayer to -1 (infinite repeat). Then it should work.
And you should also set the UIBackgroundMode plist key to an array of one string called "audio"
It's probably a dirty workaround, but in the past I have used the proximity sensor to turn off the screen instead of locking the phone. Simply place the phone upside down and the screen will turn itself off.
[[UIDevice currentDevice] setProximityMonitoringEnabled:YES];
This will allow you to retain full control over the device, while the screen does turn off.
I have developed an iPhone app which gets the microphone recorder inputs every second using NSTimer, calculate the amplitude of sound, and take appropriate action if required. I have noticed that when my iPhone gets locked, my application stops running(it doesn't fire the timer callback function). When I unlock iPhone, it start automatically. Could anyone please tell me how can I allow application responding when iPhone gets locked? Is there any other way around such that iPhone shouldn't get locked when my application is running? What should be Apple's recomendation on this?
I found this article but not sure it is correct way to do.
Thanks.
You cannot prevent timer from being stopped when application goes into idle state. Only one possible way is to disable idleTimer of the application.
application.idleTimerDisabled = TRUE;
//or
//Disable screen dimming if no user input occur on device.
[[UIApplication sharedApplication] setIdleTimerDisabled:YES];
I have an alarm clock app which works on a timer. When the alarm is meant to go off and the screen is switched off, it should start playing audio from AVAudioPlayer, but it doesn't. Then when i turn the screen back on, i can see that the rest of the code fired as expected (a stop button is now on the screen). How do i get the AVAudioPlayer to play when the screen is turned off?
Is there any way for me to detect that the screen is turned off?
#zoul is correct that using the default audio session category will result in sound form your app being disabled when the user locks the screen. See the Audio Session Programming Guide for direction on which audio session category you should choose.
However, even once your audio session category is set correctly, you'll have another issue to tackle. When the screen is switched off, your application gets suspended per Apple's documentation here: Executing Code in the Background. This means that when the user locks their phone or switches to a different app, your app will stop running and stay in a freeze-dried (task-suspended) state until the user activates your app again. At that point, your app resumes execution as if nothing happened. That's why it appears that your app has continued to function when you unlock the screen.
For alarm behavior, you'll probably want to schedule the delivery of a local notification. A local notification will ensure that the system provides your alert to the user at the time you request, and allows the user to activate your app. See Scheduling the Delivery of Local Notifications for details on how to accomplish this.
Maybe you have the wrong audio category? See the documentation for AVAudioSession, especially the audio category settings.
I have used:
[UIApplication sharedApplication].idleTimerDisabled = YES;
in a number of Apps developed and running under iPhone OS 2.x and never had any problems with it. They were clock apps so needed to run constantly and ignore the iPhone's idle Timer setting.
However, trying to achieve the same with a new App running OS 3.0 (and which needs to be deployed under 3.0 as it uses some 3.0 APIs) I've found the idle Timer to be either ignored or inconsistent.
My App plays music from the iPod library and when the music is playing it auto-locks regardless of the above setting. But once you unlock it, it then doesn't auto-lock again unless you play music again, in which case it locks again after the iPhone auto-lock time setting.
I'm amazed no-one else has come across this as I imagine it would affect a large number of Apps.
Just to clarify:
1. The above code is in ApplicationDidFinishLaunching
2. I know that the phone won't auto-lock when testing from xCode regardless of settings
If anyone has any thoughts I'd be very grateful...
Our app uses the MPMediaPLayer. We also had the idleTimerDisabled=YES code in the ApplicationFinishedLaunching, which works EXCEPT if untethered, and there is already a current nowPlayingItem which is left playing (or unpaused, if paused at app startup). Obviously this is all with the Settings -> General -> Autolock set to some timed value.
By adding idleTimerDisabled=NO, immedately followed by idleTimerDisabled=YES in one of the other bits of code AFTER we had figured out what bit of music we would get playing seemed to solve the problem. Just setting it to YES was insufficient.. and subsequent queries had always indicated the correct value (YES).. so it appears the Apple code ignores the setting of the value IF there is a current piece of music and that is not changed by your code.. but does notice a change of value.
This is all under iOS 3.0.
Even in 2015, using iOS 8.2, this bug is still alive and kicking.
Here's my solution, using XCode 6.2.
iPhone - phone goes to sleep even if idleTimerDisabled is YES
Basically, even now, in 2015, the only way to safely make sure that the device doesn't go to sleep is to repeatedly call a piece of code to keep the device awake.
-(void)callEveryTwentySeconds
{
// DON'T let the device go to sleep during our sync
[[UIApplication sharedApplication] setIdleTimerDisabled:NO];
[[UIApplication sharedApplication] setIdleTimerDisabled:YES];
}
Sounds like a bug, file with Radar - I am not too surprised this has not been seen much as there are probably not a lot of apps that try to lock the screen open and play music.
Having same issue. It does work when the device is plugged in. You can press lock button on top, and my NSTimer fires later and causes a vibrate. However if the device is not plugged in pressing the lock button puts the device to sleep. Any solution would be greatly appreciated.
iCodeblog posted about the idletimer, I said it didn't work, and the person who develops 'cute clock' was nice enough to reply. You have to do a hack, play a 1 second or longer silent sound every 10 or so seconds with NSTimer. This keeps the device awake even if the user hits the lock button.
I develop Seconds - Interval Timer for iPhone and iPod touch and I've had no end of trouble with this. The idea of my app is that people create timers based on a number of intervals where each interval can have it's own playlist or track played.
In iOS3 I had the problem that I couldn't disable the idle timer by just setting idleTimerDisabled = YES. In the end I came up with the same solution as Neil whereby I would periodically set it to NO, then immediately to YES again. This seemed to work.
I'm now updating the app to iOS4 (I know, iOS5 is just around the corner...) and now I have the opposite problem. If the MPMediaPlayer changes track before the idle timer reaches it's limit it gets reset. I've just tested this by creating an interval in my app that was 55 seconds, my auto-lock was set to a minute. At 50 seconds the screen dimmed as it prepared to lock, but at 55 seconds when the music changed it went back to full brightness and then didn't lock as it should.
Overall, the implementation of this seems flakey at best.