Here's 2 binding issues I'd like to share with you, related to selector name and parameters when configured in IB.
I have CoreData objets retrieved through an ArrayController and populated in a NSTableView. All the binding is made through Interface Builder. Each row contains a button that should check an url (one of the properties of the entity).
1. To make the button fire, I first tried to bind it this way:
For the target:
- Bind to: File's owner (in this case, a
ViewController) - Model Key Path:
self - Selector Name:
revealInFinder:
For the argument:
- Bind to:
Table Cell View - Model Key Path: ObjectValue
- Selector Name:
revealInFinder: (<automatically set>)
When I click the button, the function revealInFinder(object: NSManagedObject) that I wrote in the ViewController is simply never called: I tried with or without argument, with or without a colon, nothing happens: no breakpoint triggered, no message in the console.
I can put random chars in the selector name, I don't even get a
"unrecognized selector name"!
... Same thing if I change the name of the function in the ViewController, or simply remove it: Nothing happens and no errors in console (of course, I've checked: the owner of the File is set to be the ViewController, but the view wouldn't show up anyway).
As the binding are made in IB and not in code, it's difficult to trace and debug my mistakes (I also put -NSBindingDebugLogLevel 1 to the “Arguments to be passed at launch”, as recommended here: https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/CocoaBindings/Concepts/Troubleshooting.html). But how am I supposed to handle something that is apparently a "non-event"?? Sure I'm missing something here but what?
2-I've decided to bind the button in a different way:
For the target: (without argument at first)
- Bind to: Table Cell View
- Model Key Path: ObjectValue (so the Core Data's entity, right?)
- Selector Name: revealInFinder:
This works, as I created NSManagedbject subclasses for my entities, and wrote extensions for them.
The problem occurs when I add an argument, as I need to get the managedObjectContext to do some fetching inside the function:
For the argument:
- Bind to: File's owner
- Model Key Path: self.managedContext (the moc is set in the viewController)
After a bunch of "unrecognized selector sent" messages, I managed to write this function (not really sure why it's only called with the "_"):
func revealInFinder(_ managedContext: NSManagedObjectContext)
but the passed argument remains 0x00000000... (<uninitialized> in the console).
I changed the Model Key Path by removing the self., and then bound it to the managedObjectContext of the ArrayController instead):
- Bind to: Array Controller
- Controller Key: ArrangedObjects
- Model Key Path: managedObjectContext
The moc still remains uninitialized.
Why is my first try not triggering any action?
Why the argument is uninitialized in the second try (not even "nil")?
