Interface-Builder outlets causing odd display behaviour - cocoa

I've been working today on adding a sheet to the main window of my application. After having trouble seperating the two (main view/controller and sheet view/controller), I've gone with just having both views in the same xib and both controlled by the main controller. Now that it appears when the beginSheet method is called, I've designed the form, and hooked it up to the IBOutlets/Actions on my controller.
This is where the problem is. With no bindings between the forms objects and the controller, it displays perfectly. But when I connect buttons to IBActions, and text fields/imageviews to IBOutlets I encounter some weird display problems. I'm talking buttons not displaying (but the actions being executed when clicking where they should be), borders of NSBox's not showing and textfields not taking any typed text and displaying (still blank) further off the viewable area of the panel.
I discovered that I could rectify this by resizing the panel a little, but that's not usable. I did get it working fine with 3 textfields and 3 buttons and just close/minimize enabled (not that they actually seem to do anything to a sheet), but now I've hooked an imageview up to the controller and the one of the buttons isn't displaying again.
Is this something to do with the number of outlets/actions I'm using (The actual main window doesn't actually have any extra ones) or is it IB being buggy or me doing something very wrong?

My first suspicion would be that there is an exception being thrown somewhere during drawing the sheet. In my experience, that's usually the case when you get half-drawn controls like you're describing. Check the debugger console in Xcode to see if any error messages are being printed out there. You can also add a breakpoint on objc_exception_throw to have the debugger stop when an exception is thrown, that might shed further light on where exactly the problem is coming from.

This issue went away when I reconstructed the sheet from scratch. I do not know what caused the issue, but if anyone has a similar problem I would suggest trying to reconstruct it in a new sheet.

Related

Weird NSOutlineView crash

I'm experiencing weird crash in NSOutlineView: when i click "collapse" button, app crashes immediately and even "exception breakpoint" doesn't help to see where the problem is.
I've tried to run app without debugger, and reproduced the problem. Once app crashed, i've got OSX crash window and was able to extract crash message from there:
The window has been marked as needing another Update Constraints in Window pass, but it has already had more Update Constraints in Window passes than there are views in the window
there also call stack, but it won't help since crash happening inside libsystem_c.dylib, so i'm not posting it here.
It seems there is something wrong going with auto layout. Absolutely have no idea about next steps. Please give me an advice!
Also, one more thing, that began only after update to OSX Mojave.
After hours of debugging and testing, i noticed that that message is caused by "infinite layout loop".
Different code, related to outline view was causing NSSplitView to layout. And delegate method - (CGFloat) splitView:(NSSplitView*)sender constrainMinCoordinate:(CGFloat)proposedMinimumPosition ofSubviewAt:(NSInteger)dividerIndex has been called about 200 times prior to crash.
It's hard to catch this bcs it's not actually infinite recursion, so just debugger doesnt help a lot.
I just added simple code that helped me to identify the issue:
static int a = 0;
NSLog(#"Layout: %d", a++);
Hope my experience will help somebody else!
For anyone who is having the problem in Xcode 14 and macOS using SwiftUI:
I just had the same crash by hiding a view with an animation. My main view contains two views, one view contained an empty ScrollView, which didn't cause a problem by itself, but by changing it's size it crashed. Just adding a basic Text within the ScrollView solved my problem and the app doesn't crash anymore.
I updated my build to IOS 14 and Mac OS 20.15.6 and the error went away.
try turning off 'Use Auto Layout' checkbox in nib (in File Inspector tab).
May have to disable it for each and every view.
Also, unrelated, but Mojave forces you to use Core Animation.
Most of my nibs have 'set wants layer' turned off.
However, in one of my nibs I had a stray setWantsLayer checkbox checked.
when I unchecked it, the view (NSSearchField) drew properly

Tabbed application troubles in xcode

I am working with my first tabbed application in xcode. I am just testing with some stuff since I'm relatively new to programming. I am just using the 2 views already put into the template. I am putting a slider into the first view and am going to attach it to a text box with numbers. But that isn't the problem! This is probably really stupid and simple, but when i run the application just to see the stuff on the simulator, it is just showing a black screen. NO CLUE WHY! But its killing me and would love some help!
You are not suppose to make connections in AppDelegate. You should use a ViewController for each class. I.E. FirstViewController, SecondViewController. AppDelegate is usually only used for calling save/restore messages.
You are getting the error because the storyboard view is assuming you are assigning it to the correct view. When you create the storyboard say you named it TestApp. Then, you should have a few classes. TestAppDelegate, TestAppDelegateFirstViewController, TestAppDelegateSecondViewController. Or something along those lines. FirstViewController should connect to the first view on the tab view. The Second should attach to the second.
AppDelegate is almost never used for UI. I would suggest you find a book on the matter. I'll suggest "iOS Programming. The Big Nerd Ranch Guide". It helped me a lot when I started.
Photo Exmaple:
I did end up starting a new project. Weird that the black screen showed up.. not really sure why that error was popping up.. I'm not really that knowledgable about the different errors and bugs that a program can have yet! Getting closer though!

Strange behavior with accessory views on NSSavePanel and NSOpenPanel in sandboxed app

I have a problem with accessory views on NSSavePanel and NSOpenPanel.
Sometimes, (very often) when I open one of these panels the accessory view does not work (the view is shown but controls seem disabled).
I'm using this code to show the panel:
[openPanel beginSheetModalForWindow:appWindow completionHandler:openPanelHandler];
This only happens when app-sandbox is enabled.
After much testing I found out that what was happening was that the view was being misplaced (not attached to the panel).
When I open Mission Control and move the mouse pointer over the app windows I noticed that an "invisible" window hilighted and when select it I can take control over the accessory view (all controls work) but it appears detached from the open or save panel as shown on the screenshot.
I tried to create a new app just to test this behavior but was not able to reproduce it, so I suppose that has something to do with my app.
Any hint of what I may be doing wrong?
I don't want to code everything from scratch just to solve this issue.
Edit
Just a side note, when I close the window, just before the window close the accessory view flashes with the correct values for the controls. It appears that the application does not add the view in time for showing the panel.
Update 1
I subclassed the view that is used as accessory view and noticed that the
- (void)viewWillMoveToSuperview:(NSView *)newSuperview
is called, but
- (void)viewDidMoveToSuperview
never gets called even when the view is shown correctly, is this the normal behavior?
Update 2
I confirmed that - (void)viewDidMoveToSuperview should be called, on the test app both methods are called.
I also noticed a slight difference between my app and the test app. On my app the panel just slides down but on the test app the panel appears to "flip down" (don't know exactly how describe). The way the panel appears is irrelevant to me, I just noticed that it is not shown the same way.
After trying many things I concluded that the problem had to do with ARC (Automatic Reference Count) settings for the project.
In my case I had enabled ARC on target but not on project, after enabling ARC on project (and dealing with resulting errors and warnings) everything works perfectly now.

Inactive Controls on ViewController despite working referencing outlets

I was wondering if anyone else has seen this. I would include a screen shot but it would be unilluminating, showing all the referencing outlets and event handlers hooked up exactly as they should be, the same thing that was working perfectly before I made some changes. I had a very simple UIView with some text and a single control which I edited to have more controls, and after building none of them worked. The IBOutlet variables all worked, I was able to set text and control states on viewWillLoad, but all control were inactive. They were enabled, allowing user interaction, I even tried setting their enabled properties in code. Dead.
Finally I created a new view, copied and pasted the subviews into it, hooked up the event handlers and referencing outlets, and it worked right away.
Does anyone have any insights to share on this? I tried cleaning the project, rebooting the machine, the whole gamut. OK, "the nib must have been corrupt," but why?
Thanks for any insights.

Flickering NSTextFields

I have two NSTextFields in a xib file I'm using to display some preferences to users.
There is a save button that I wanted to be unusable until these preferences have been filled out. For some reason, this made all the NSTextFields in the xib file totally unusable as well (it was as if they had been disabled).
When I enable the NSButton, everything works--but with a catch. Whenever I focus the cursor or type in one of the NSTextFields, the text inside flickers. It's really disconcerting.
There's no custom code powering the UI elements.
Any help is greatly appreciated.
It appears as though this is a bug in Interface Builder.
After deleting the NSTextFields that were flickering and adding them back in IB, the flickering stopped.

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