I'm writing a pretty straightforward ObjC app. (The only minor complexity is that it uses an external library called Chilkat for some basic networking, but I don't think that that's relevant.)
Occasionally, my project spontaneously pops up this warning message:
May 14 01:24:01 Neovenator-2.local Project[22645] : void
CGSUpdateManager::log() const: conn 0x4b29b: spurious update.
And I have no idea how to handle or even interpret it. There's nothing in my project called CGSUpdateManager, and my project doesn't call a log() function anywhere. I can't even reliably reproduce it, but it's popped up often enough to raise my interest level.
Searches at both Google and here for the term "spurious update" reveals a lightly scattered set of conversation, but nothing relevant to my project. Meanwhile, a Google search for "CGSUpdateManager" reveals it's something to do with Swift, which I'm not using at all.
Can anyone help me understand what this means? Or should I just disregard it?
Make sure to call super in viewDidLoad, viewWillAppear and viewWillDisappear.
Sorry, my code with correct Highlight/indentation:
- (void)setNeedsDisplay
{
//#if 1 //TEST (suppose we are only called by us)
if(wvImageRep_DoRebuild)
//#endif
[super setNeedsDisplay]; // "spurious update" ?
}
It's an example (#see my full response), it helped me
Related
I've noticed the following error popping up in the console when running my app on iOS 9 when using a storyboard. I'm using xCode7. Is this something I need to be concerned about?
-[UIApplication _handleNonLaunchSpecificActions:forScene:withTransitionContext:completion:] ** unhandled action -> <FBSSceneSnapshotAction: 0x176bfb20> {
handler = remote;
info = <BSSettings: 0x176a5d90> {
(1) = 5;
};
}
There is nothing wrong with your code. This is a logging message internal to Apple, and you should file a radar about it.
There are two hints that show that this is probably Apple's code:
The underscore leading the method name _handleNonLaunchSpecificActions:forScene:withTransitionContext:completion is a convention indicating that the method is private/internal to the class that it's declared in. (See this comment.)
It's reasonable to guess that the two letter prefix in FBSSceneSnapshotAction is shorthand for FrontBoard, which according to Rene Ritchie in "iOS 9 wish-list: Guest Mode" is part of the whole family of software related to launching apps:
With iOS 8, Apple refactored its system manager, SpringBoard, into several smaller, more focused components. In addition to BackBoard, which was already spun off to handle background tasks, they added Frontboard for foreground tasks. They also added PreBoard to handle the Lock screen under secure, encrypted conditions. [...]
I have no idea what the BS prefix in BSSettings is for, but
BS is shorthand for BackBoard Settings, and an analysis of this log message would indicate that it's not anything you did, and you should file a radar with steps to reproduce the logging message.
If you want to try and grab a stack trace, you can implement the category linked to here. Some would argue that overriding private API is a bad idea, but in this case a temporary injection to grab a stack trace can't be too harmful.
EDIT:
But, we still want to know what this action is. So I put a breakpoint on -[UIApplication _handleNonLaunchSpecificActions:forScene:withTransitionContext:completion] and started printing out register values and found a class called FBSceneImpl which had a whole bunch of information about my application:
We are able to find out which private method is called next (stored in the program counter, instruction pointer, register 15.)
I tried finding the un-handled FBSceneSnapshotAction referenced in the log, but no dice. Then, I subclassed UIApplication, and overrode _handleNonLaunchSpecificActions:forScene:withTransitionContext:completion. Now I was able to get at the action directly, but still, we don't know what it is.
Then, I looked at the FBSceneSnapshotAction again. Turns out it has a superclass called BSAction.
Then I wrote a tool similar to RuntimeBrowser and looked up all of the subclasses of BSAction. It turns out that there's quite a list of them:
The two method names we have (one from the log and one from the program counter on the devices) indicate that these actions are used under the hood for passing actions around the system.
Some actions are probably sent up to the app delegate's callbacks, while others are handled internally.
What's happening here is that there is an action that wasn't handled correctly and the system is noting it. We weren't supposed to see it, apparently.
AFAIK, the info above is related to iOS during snapshot the screen (i suppose for double click home multitask related behaviour).I deeply investigated my application and seems that it does not get any side behaviours. You can safely ignore it, for now.
You can use the following gist simple category to test yourself against the calls to the above function:
I have figured it out, it will happen when you have IBAction method declared in .h or .m file but you have not bind it to any control.
.m example:
- (IBAction)click:(id)sender{
}
but not assigned this method to any control in storyboard.
haven't find out why it happens in my app, but at least you can catch the exception, if you want to keep this from popping up in your log pane. It's not a solution, but it might give you more insight why it is happing by inspecting any of the arguments that are passed in the catch.
swift 2 version:
import UIKit
extension UIApplication {
func _handleNonLaunchSpecificActions(arg1: AnyObject, forScene arg2: AnyObject, withTransitionContext arg3: AnyObject, completion completionHandler: () -> Void) {
//whatever you want to do in this catch
print("handleNonLaunchSpecificActions catched")
}
}
Is there a symbolic breakpoint or something that will trap the following warnings, so that the erroneous code can be more easily found?
Attempt to present <> on <> while a presentation or dismiss is in progress.
Trying to dismiss the presentation controller while transitioning already. (<>)
I don't have a specific problem to solve, just looking for an answer to this question, which could just be "no".
When these errors occur, how do you find out the present/dismiss call causing the problem and/or the present/dismiss that is in progress?
Maybe a little more context would help us answer your question ?
Are you using UIViewControllerAnimatedTransitioning ?
When are you having this issue happening ?
If you want to debug, you can use UINavigationControllerDelegate method for your convenience :
- navigationController:willShowViewController:animated: or
navigationController:animationControllerForOperation:fromViewController:toViewController:
If you're not already using it for your animation.
The best I've found so far is to run with Allocations instrumentation and "Record reference counts".
Then you can find the specific instances referenced in the logs by their address.
This will have recorded the stack traces when that object was created, presented, etc, as they all involve changes in reference count.
I only rarely use #synchronized, but as far as I can remember (meaning around Xcode 3.2 or something), it never suggested #synchronized when using the auto-completion, and still never does.
I do get suggestions when typing '#', like #autorelease, #encode, #selector and so forth.
Is there any known reason for this ? I wasn't able to find any related topic. It's been bugging me, because it gives me the feeling that this is not a valid method to handle concurrency in iOS.
#synchronized does not appear when using auto-completion because Apple has not mapped that keyword to any code sense implementation.
Per Apple's suggestion, I have filed a bug report.
However, I can offer an auto-complete solution.
You may create an #synchronized snippet that can be auto-completed or drag and dropped into your code.
Copy/paste the code below into one of your Xcode documents.
Select the new code and drag it to your snippets library.
Double-click the new snippet and click edit.
Enter #synchronized for the completion shortcut.
For more info: http://nshipster.com/xcode-snippets/
#synchronized(anObj) {
// Everything between the braces is protected by the #synchronized directive.
}
I am working on trying to make a splitview based application. I am trying to use Apple's MultipleDetailView example code
http://developer.apple.com/library/ios/#samplecode/MultipleDetailViews/Introduction/Intro.html
I have never really used example code like this (I usually just atart from scratch). All i did was copy the code into the correct classes of my app, but when I try to run it on the simulator the app doesn't open.
I feel like I am maybe forgetting something obvious, since I didn't code it myself.
Thanks!
The usual debugging technique applies. Put a breakpoint somewhere early in the program -- the first line of main() for instance, and debug from there. Do you hit the breakpoint? If yes, move forward through the code until you find the line that causes the problem. If no, try to back up even further if you can, and also look for any clues as to what's going wrong. If the app is running at all, there should be some sort of error message in the console output.
"...the app doesn't open" doesn't tell us nearly enough to help you. Something like "the app delegate is instantiated, but it's window and splitViewController properties are nil" goes much further toward getting to the root of the problem.
I'm using Localitics and ComScore libs for collecting some statistic for my app. And I have a problem with memory leaks. If any body use such libs, and know how to solve this problem. Or, maybe, it's not a problem?
in more details: after, when i commented
// [[LocalyticsSession sharedLocalyticsSession] startSession:LOCALYTICS_KEY];
// [[CSComScore census] notifyStart:COMSCORE_ACCOUNT_ID andSecret:COMSCORE_SECRET];
in didFinishLaunchingWithOptions in my appDelegate, all leaks disappear.
update
comScore
I'm using only base functions: in app there no code related to comScore except "notifyStart".
localitics
I used http://www.localytics.com/documentation/iphone-integration/ for integration this lib. My appDelegate looks exactly as said in instruction. for loging i'm using -
-(void)viewDidAppear:(BOOL)animated
{
[[LocalyticsSession sharedLocalyticsSession] tagScreen:#"Near Me."];
//here I have warning: ... may not respond to ...
}
here you have screen shot of my Performance tool:
hope it will help.
I am not sure exaclty what is wrong with your memory there. I use touchwizards.com for analysis, it has some great interaction analysis for iOS like heatmaps and more