All
I have two audio files (caf) which I want to my audioplayer play one after the other. Below is the code I am using
AVAudioPlayer *lSoundPlayer;
AVAudioPlayer *lSoundPlayer1;
NSTimeInterval timedelay = 2;
[lSoundPlayer play];
[lSoundPlayer1 playAtTime:timedelay];
When I compile I am getting a warning that the AVaudio player might not respond. When I try to execute I am getting exception. Can someone please help
You are sending a message to an object which is neither allocated nor it is initialized.
I suggest you have a look at the class reference and ask again if you have any further questions: http://developer.apple.com/library/ios/#documentation/AVFoundation/Reference/AVAudioPlayerClassReference/Reference/Reference.html
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In my crash logs for my latest app version, I got an NSFastEnumerationMutationHandler followed by a crash referencing HKAnchoredObjectQuery initWithType for my code, but I am not intentionally mutating the NSMutableSet sources over which I am fast enumerating.
Here's my code:
for(HKSource* source in sources){
NSPredicate *predicate = [HKQuery predicateForObjectsFromSources:[NSSet setWithObject:source]];
HKAnchoredObjectQuery *newQuery = [[HKAnchoredObjectQuery alloc] initWithType:quantityType predicate:predicate anchor:anchor limit:HKObjectQueryNoLimit completionHandler:^(HKAnchoredObjectQuery *query, NSArray *results, NSUInteger newAnchor, NSError *error) {
completion(results);
}];
[healthStore executeQuery:newQuery];
}
Any suggestions as to why I am triggering NSFastEnumerationMutationHandler? I am not explicitly touching sources nor have I made a copy of it...is there a way HealthKit could be modifying the source? Even if it were, I would think that modifying source shouldn't trigger this as I am not directly touching sources. Any trouble-shooting advice or error-spotting would be much appreciated.
Here's the exact text from the crash log:
Latest Exception Backtrace:
1. libobjc.A.dylib objc_exception_throw
2. CoreFoundation _NSFastEumerationMutationHandler
3. App name 0x1000d8000
4. App name 0x1000d8000
5. App name 0x1000d8000
6. HealthKit _79-[HKAnchoredObjectQuery initWithType:predicate:anchor:limit:completionHandler:]_block_invoke <---this must be referring to my code above, as it's the only call to initWithType inside a fast enumeration
7. HealthKit _81-[HKAnchoredObjectQuery deliverSampleObjects:deletedObjects:withAnchor:forQuery:]_block_invoke_2 <-- this is an internal HealthKit call. deliverSampleObjects is not a publicly listed method of the interface.
I have not had a crash in the sim or on my phone, so this is the only info I have to go on.
Some code that gets called by the block named completion() in your code snippet is iterating over another collection and is doing so while that array is being modified. Keep in mind that the completionHandler of HKAnchoredObjectQuery runs on a background thread, so your code may be performing unsafe concurrent operations on objects when completionHandler gets called.
It looks like this happens in a block somewhere in a method named
[HKAnchoredObjectQuery initWithType:predicate:anchor:limit:completionHandler:]
So my guess is that the block in question is the completion handler, and the completion handler gets called asynchronously - while someone else is iterating through the same array and maybe modifying it.
Unfortunately this error doesn't show who is causing the trouble, only who is finding the trouble. I'd set a breakpoint on your own callback, check if it is called from a fast enumeration, and try to figure out who else might be modifying the data. Good luck.
I am new to working with Objective-C and Cocoa.
I have followed the sample code for playing a movie with Quicktime that is on here. I am wondering how to expand it so that I can load multiple QTMovies at the beginning of the program, and then play each of them when requested with minimal latency.
My initial strategy was to create a class that holds a QTMovie object and the methods for loading and playing it. Then in my main class I'd have a list of these MovieContainer objects.
When I try implementing this, I get a QTMovieLoadStateError during the loading of each QTMovie with the error message
Domain=NSOSStatusErrorDomain Code=-2098 "The operation couldn’t be completed.
(OSStatus error -2098.)" (component is not thread-safe)
Am I going in completely the wrong direction, or am I merely missing a few lines of code that would make this "thread-safe"?
Thanks for any help.
Before working with QTMovie objects in a background (non-main) thread you need to call:
[QTMovie enterQTKitOnThread]
or
[QTMovie enterQTKitOnThreadDisablingThreadSafetyProtection]
Which one to choose would depend on the codec of your movie file. The second variant will allow non-thread-safe components; for some rare codecs this would be the only way.
The call must be paired with:
[QTMovie exitQTKitOnThread]
I am working on an app, where I display the data entered by user in a PDF file. PDF File is also created dynamically.
All this is fine.
I have implemented QuickLook framework to display the pdf file. When I call the QL framework, PDF file id displayed quite fine but when come back to the calling screen, my app crashes without any crash log or memory warnings.
I am calling QL with below code:
[[self navigationController] presentModalViewController:qlPreviewer animated:YES];
logs created are
DiskImageCache: Could not resolve the absolute path of the old directory.
[Switching to process 3070 thread 0x17603]
[Switching to process 3070 thread 0x15503]
This is quite interesting.....
When I run the same program in Instruments to check for leaks and Memory Management, i can only find leaks when PDF document is scrolled and all the pages are viewed.
However, interestingly there is no app crash that I can see.
Also, I did try with ZombieEnabled = YES and without it but no app crash with Instruments.
I am quite clueless on how to interpret this and have been trying different things to solve this. Also, I have tried UIWebView but the result is the same.
I was again trying something to check out the issue and found something interesting.
When i execute the code directly from X-Code - i get the crash in as explained above.
In other instance, if I execute the app by clicking on the app in the sim... no crash
I am yet to check this on device. Can someone confirm the crash on the device?
Also, Google does not have answer to this question.
Thanks in advance for your answers.
Can anyone shed some light on this?
I'm having the exact same issue.
As a workaround, you can disable or remove your 'All Exceptions' breakpoint. This might make debugging a little more difficult, but it's not as bad as having to relaunch the application all the time.
This is the breakpoint causing the issue. I had set it so long ago that I'd forgotten it was there
Deleting application from device helped me to solve this problem.
Maybe also at first you should try "Product > Clean" to ensure that all resources will be copied to your device.
I was able to fix mine with this code:
FirstViewController.h
NSURLRequest* reqObj;
#property(nonatomic, retain) NSURLRequest* reqObj;
FirstViewController.m
reqObj = [NSURLRequest requestWithUrl:url cachePolicy:NSURLRequestReloadIgnoringCacheData timeoutInterval:60.0];
NSURLConnection* conn = [[NSURLConnection alloc] initWithRequest:reqObj delegate:self];
then instead of loading it on my view after this line i waited for the connectionDidFinishLoading then load it to my view
Interesting: This has just started with my app too. No errors when checking for leaks but running the app in the sim actually is causing a Breakpoint, not a crash. I can hit the continue and the app keeps running, no problem.
My issue also is relating to a PDF, but I'm just using a web view to display a PDF from the app bundle. I've checked everything in the dealloc, it's all good, this may be a iOS 5.1 bug. I will update as I learn more.
#JimP, It isn't an iOS 5.1 bug. It has just started happening to my app as well, on iOS5.0. It seems to only affect pdfs of more than one page length, and seems to trigger most commonly on scrolling past the end of the document (although sometimes earlier also). It also seems to happen more often on a second load.
This could happen when you delete the object reference in code but having its reference in xib. Delete the outlet that you no longer need.
Just ran into this problem of loading a pdf file in an App I am converting to iOS 8. This App has been running fine since the first iPhone. I just removed the All Exceptions breakpoint to work around it.
I don't know if it's the same problem but I had an issue where switching from a PDF view to another more than three times via the tab bar controller caused a crash.
Turned out that embedding the views I was switching to within Navigation controllers put a stop to the crashing.
I have a mac app that writes camera data to a file then uploads that file on an [NSTimer] to a server. However, after the camera runs for a while it closes itself and I see this in the log: * QTCaptureDeviceInput warning: The device "FaceTime HD Camera (Built-in)" was closed while still being used in a capture session. Make sure that the session is not running before closing any devices it is using.
No other apps are open that can use the camera in the test case and the object for the device is not being released by me. I have gone so far as to call retain on it to prevent this, to no avail.
I looked at Apple's docs and nowhere that I found did it talk about the camera being shut off by the system, so what could be causing this. In the meantime I have some code that periodically checks if it is open and if it isn't calls open on it.
One thing I forgot I am using this notification and it is being fired: QTCaptureDeviceWasDisconnectedNotification
Well, it took a while but I found the issue. When you you are pulling image data from a running QTCaptureDevice you need to work with individual frames via the following delegate method. If you fail to properly release the buffers on each run the camera will eventually close by itself. Please note the code below is CORRECt; I attached it to help anyone else reading this question. Hope this saves someone the time it costed me...
- (void) captureOutput:(QTCaptureOutput *)captureOutput didOutputVideoFrame:(CVImageBufferRef)videoFrame withSampleBuffer:(QTSampleBuffer *)sampleBuffer fromConnection:(QTCaptureConnection *)connection {
CVBufferRef bufferToBeReleased;
CVBufferRetain(videoFrame);
#synchronized (self) {
imageBufferToRelease = imageIWanted;
imageIWanted = videoFrame;
}
CVBufferRelease(bufferToBeReleased);
}
Sorry to bug twice so quickly, but since people were so kind in their informative responces, I figured it couldnt hurt to ask another question.
The same program i tried to make it rather swanky and have a main screen which allows you to click on a button which leads to a limited options screen. This lets you switch the music on or off. Or at least it should do.
The music running code is in the main file (game.m), under the following:
//Music
[Settings setMusicEnabled:YES];
music = [SPSound soundWithContentsOfFile:#"music.caf"];
channel = [[music createChannel] retain];
channel.loop = YES;
channel.volume = 0.25;
if([Settings musicEnabled]){
[channel play];
}
I apologize for the strange format, but it is Sparrow framework. basically, the Settings file contains the class methods I am trying to use. If the methods cause YES, the music is on. If it is No, then the music is off.
settings.m
static BOOL isMusicEnabled;
#implementation Settings
+ (BOOL)musicEnabled
{
return isMusicEnabled;
}
+ (void)setMusicEnabled:(BOOL)value
{
isMusicEnabled = value;
NSLog(#"SME? %i", isMusicEnabled);
}
#end
Now, the options file is working and i tested that section. The program is reading that isMusicEnabled is getting a new value, thus musicEnabled is being altered as well, so there should be a change and the music should be switched off.
However, nothing happens. I have tried to use debugger, but I am not very good at it and I dont understand a lot of the information i am given. I do understand that the problem is sending the message from Settings file to the main/Game file.
I would appriciate anyone's help who could enlighten me as to how this could be solved.
I'm not familiar with Sparrow Framework, but let me make a guess anyway.
[channel play]; starts playing the music in background until the channel is asked to stop playing.
Changing the isMusicEnabled does not trigger any code to stop the currently playing music. When you change the value in Settings, you should inform the channel to stop (most probably by somehow accessing the channel and calling [channel stop].
There's another problem - isMusicEnabled is just a variable in memory, your program will not remember its state between restarts. And Settings are usually supposed to be remembered.
To summarize I see two problems: persisting settings between restarts first and informing about change of settings second. To remember settings I suggest you look into NSUserDefaults class. To inform the channel to stop playing you have couple of options - depending on you skills. Easiest is to simply access the channel variable from within the setMusicEnabled and call stop. Another option would be to use notifications, but for a beginner programmer that is more complicated (look for NSNotificationCenter if interested).