I have the following situation: I do a check when user touches screen, to check if it matches some bounds if menuButton.frame.contains(coordinates) {
Then, I try to push a segue like this performSegueWithIdentifier(menuButton.whichButton(menuButton.tag), sender: self) My problem is that the first time the segue performs, it has a huge delay (about 3-4 sec). Afterwards, everything runs as it should. I did check for main thread and I am in the main thread. Can you please help me?
I found the answer, as strange as it may appear, it was related with the fonts. I added some fonts, selected them in interface builder, but of course I didn't check the target membership. So the system was looking for them, I think, before reverting to default font, thus creating the lag. I hope it helps someone at some point.
Have you tried to run on a device or only in the simulator? Just to make sure...
You can try this too:
dispatch_async(dispatch_get_main_queue(),{
self.performSegueWithIdentifier(mysegueIdentifier, self)
})
Related
I've been trying to use the following method on Swift 5 to display the Bluetooth Accessory Picker:
DispatchQueue.main.async {
EAAccessoryManager.shared().showBluetoothAccessoryPicker(withNameFilter: nameFilter, completion: nil)
}
But I get the following error:
A constraint factory method was passed a nil layout anchor. This is not allowed, and may cause confusing exceptions. Break on BOOL _NSLayoutConstraintToNilAnchor(void) to debug. This will be logged only once. This may break in the future.
I've tried adding a Symbolic breakpoint, but it doesn't trigger. I've also tried calling this method from other parts of the code with different views, but still no success.
I'd really appreciate some help with this issue!
It broke when Apple introduced the new Scene-based lifecycle. Roll back to the classic one and it starts working again. More details here: https://stackoverflow.com/a/70823487/415982
i am making a very complicated app with a lot of classes.
my app worked great and i worked on it for the last month.
the last time i worked on it i added a function and it worked great, i saved the app and ran it a few times since and it worked. the last time i turned my computer on, it prompted me that an update for xcode is available. i updated it, and since then every time i run my app it runs with no errors but on ios simulator it shows a black screen. what can i do? i worked really hard on that app. thanks for the help in advance.
There's few issues that could happened, withou detailed description of this issue, you can try following solutions:
reset simulator
check if your initial controller is set up in storyboard(select controller and press attribute inspector, select is initial view controller):
if you're setting initial view controller programmatically, check if that controller is not nil in app delegate
another tip - try to use UI debugger, that helps a lot:
Any debug messages in the Xcode output? That usually will give a clue.
One thing I can think of, is that in your
- (void) applicationDidFinishLaunching:(UIApplication*)application
delegate, try setting the window's root view controller to your view controller. Example:
[window setRootViewController:viewController];
[window makeKeyAndVisible];
Again, the Xcode debug output will confirm if this is indeed the case though.
I'm writing an app in Swift 2.0. The app works fine in every aspect, beside one.
When I tilt the screen of both device and emulator the orientation change animation is missing. Instead of a smooth rotation I get a clunky orientation change. Portrait -> Landscape. Nothing in between.
Giving the fact that the animation should be the default, I would like to know if anybody knows the possible solution to this problem. I searched everywhere and apparently nobody has this problem, instead people try to disable that animation!
After some tests and thanks to Zell.B, I moved the code from didFinishLaunchWithOptions to applicationDidBecomeActive and everything works fine.
Deleting the applicationDidFinishLaunching method from the app delegate class can also cause the lack of animation problem. Adding it back in can fix it.
So I've been working on this bug for about a week now, and for the life of me I can't figure out what's happening.
Due to confidentiality issues I can't post too much code, but I'll do my best to explain everything.
What's happening is that we're populating a UITextField via code, and initially have the text greyed out. The user then can do one of two things:
1) Tap a button which says "commit" and a method is called which does the following method we'll call "commitData". It does the following:
Registers the commit with an undo Manager
Changes the text from grey to black
Register with our application that the text field has been updated and needs to be saved upon application close
2) Tap on the text field with the greyed out text, which then calls the following default apple method textViewShouldBeginEditing. From here we call our "commitData" method listed from option 1 like so:
-(BOOL)textViewShouldBeginEditing:(UITextView *)textView
{
if ([[self box] hasGreyedOutText])
[[self box] commitData];
[self setActiveTextView:textView];
return YES;
}
The issue we're having is that tapping the button to commit the greyed out text works perfectly fine, and we run into no issues.
HOWEVER
When we tap into the text field and trigger the textViewShouldBeginEditing method, our iPads can freeze up and make the user wait for a couple of minutes before finishing. When I mean freeze, I mean the entire iPad freezes. The iPad clock won't even update while this is happening.
When this happens, we get an error code in the console which says:
!!! _NSLayoutTreeLineFragmentRectForGlyphAtIndex invalid glyph index 2147483647
We can get the error code above to display from all of our hardware when following the steps above, but can only reproduce the freezing on an iPad 2(with 100% accuracy however).
A note on this, my co-worker has found through diagnostics that we only have about 8MB of free RAM when this error occurs. We only ever hit this little of RAM on the iPad 2 however, so this could just be a coincidence.
I have a feeling that this could be related to threading and that we might need to somehow call our method after returning YES from the textViewShouldBeginEditing method, but I'm not quite sure how I should be going about that.
If anybody has any ideas on how to fix this, or even ideas that could point me in the right direction, I would be incredibly grateful. I've looked everywhere I can possibly think of, and none of the solutions I've found relating to the error code have ended up working.
I can't debug, so in my guess it may caused by non-main thread UI operation. So, my suggestion is to make sure your UI code is in mainThread. Try this:
-(BOOL)textViewShouldBeginEditing:(UITextView *)textView
{
dispatch_async(dispatch_get_main_queue(), ^{
if ([[self box] hasGreyedOutText])
[[self box] commitData];
[self setActiveTextView:textView];
}
return YES;
}
I have been working on this app for months now and from as far back as I can remember I have never had an issue with segues. The code is unchanged in terms of calling performSegueWithIdentifier but since my recent update to Xcode 7 and iOS 9 I have not been able to tack this issue.
I have tried:
Deleting button and creating new button w/ segue link
Using a direct segue from button to view, without the use of performSegueWithIdentifier
Connecting button to new blank viewController
When I press the button, no initial load functions are called on the destination VC (Ex: ViewDidLoad, ViewWillAppear, etc). When I connect it to a blank view, the segue works fine with the same code in place.
Since the code never stops, or breaks, and just seems to "freeze" in place while still running on Xcode I can't seem to even narrow this down to whats causing the issue. I have a similar segue that is also called from another button on the same ViewController that has no issues whatsoever.
Any thoughts on the matter are greatly appreciated!
EDIT: I have narrowed the issue down to the UITextView's causing the problem. Once the Text Views were removed the page loads fine via segue. I wonder what changed between iOS 8 and iOS 9 in terms of UITextView as I will have to remove the text views and completely re add new text views.
So basically the segue was freezing because of the UITextView's I was using in the destinationViewController. The following fixed the issue:
Delete all UITextView's
Add new UITextView's
you must leave the default lorem imposed text and change this programmatically in the viewDidLoad()
This was the fix for me, and from the research I have done on the issue it seems this is a bug in iOS 9 and Xcode 7.
Cheers!
NOTE: Removing the text in the UITextView (or making it longer then ~12 characters) is sufficient to work around it, no need to delete and recreate them. This is fixed in Xcode 7.1.1 and later.
I ran into the same issue and the fixes in this post (Xcode 7 crash: [NSLocalizableString length] 30000) solved the issue for me.
The first is to enable a localisation other than the base for the storyboard (see https://stackoverflow.com/a/32688815/3718974)
The second is to turn off the base localisation (see https://stackoverflow.com/a/32719247/3718974)
I think I have the same problem: I have a UITabelView with cells created from a nib file, when a user tap a cell this method is called:
and when I have the following method prepareForSegue:: the application crashes:
if I delete the line 129 Everything is ok , the method prepareForSegue:: open the right view and the label contactName is shown with its default text.
If I modify the method as follows prepareForSegue:: get exactly what you expect, without having any type of error:
let me know if you also get the same result
Any one who is facing this issue, i solved it by turning off the "Optimize rendering for windows scale" option in Debug of simulator window. I already had tried all of the above answers but could not solve the issue.
In the method in the first viewController where you activate the segue, do you have beginIgnoringInteractionEvents anywhere? If so the screen you segue to will be frozen and will ignore interaction events like you describe. If this is the case you can fix this by adding an endIgnoringInteractionEvents method before your segue method:
UIApplication.sharedApplication().endIgnoringInteractionEvents()
self.performSegueWithIdentifier("editItemToMyGearSegue", sender: self)
I realize this is an old topic, but appears to be still relevant. I was facing the same problem in Xcode 9, iOS11. My UITextViews are embedded inside UITableViewCells. Same symptoms as described here. The tricks with default text and placeholders did nothing for me, but I solved it by turning off the scrolling indicators for the text view in the xib. They were on by default, I guess, though unused.
Edit: this is probably an important detail... the views that were hanging all had an image NSTextAttachment in the attributed string of the text view. I think the image was wider than the available table cell content. With scrolling turned off, they appear to downscale.