Styjun

I have subclassed a NumberFormatter for my specific use and it's working great when I call it from code. Here's the subclass:

 class MyNumberFormatterUnitPrice: NumberFormatter 

 required init?(coder aDecoder: NSCoder) 
 super.init(coder: aDecoder)
 setup()
 

 override init() 
 super.init()
 setup()
 

 private func setup() 
 self.format = "#,##0.00####;(#,##0.00####)"
 self.numberStyle = .currencyAccounting
 

I'm doing this because, while it's possible to set the positive and negative formats in the storyboard, you can't set those and "currencyAccounting". However, when I create a NumberFormatter in the storyboard, choose this subclass and then put it under my text cell for the column I would like to format, it appears to get overridden within:

tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int) -> NSView?

In here, I'm currently setting the cell by this logic:

let cellIdentifier = tableColumn!.identifier.rawValue
 if let cell = tableView.makeView(withIdentifier: NSUserInterfaceItemIdentifier(cellIdentifier), owner: nil) as? NSTableCellView {
 ...

I believe that I'm getting the tableviewcell from the tableview by its identifier and not creating a new one, so that should have its textfield along with it. I read the documentation and this appears to be the right way to do this. If I set the numberformatter after I've gotten the cell here, it works. But I don't want to do it this way because I don't want a giant case statement to set specific cell properties - I'd like to do this in the storyboard editor.

Any advice on how to use the storyboard editor to set the numberformatter?

Edit: Further to this, I have put a breakpoint inside where I am setting the stringvalue of the textfield, and the text is being set as follows:

textfield.stringValue = text

Looking at where the number formatter is in the debugger, it's set at the table column level - that doesn't seem right. But it's definitely still there and hasn't been written over somehow.

(lldb) e ((tableColumn?.dataCell as! NSTextFieldCell).formatter as! NumberFormatter).format
(String) $R14 = "#,##0.00####;0.00;(#,##0.00####)"

And the textfield's formatter is nil... weird.

(lldb) e textfield.formatter
(Formatter?) $R26 = nil

I'm going to go back and check the storyboard to see if maybe I dropped the formatter in the wrong place.

OK that got it. I'm obviously a noob to MacOS development and I just trusted that dropping the number formatter into the column I wanted was going to put it at the cell level... that's NOT true!.

In this image you can see the right and the wrong way to do this if you're expecting to format the cell. The right way is highlighted. You have to open the hierarchy up right down to the text field for the cell. The wrong way is above and you'll see it under the "text cell" which is actually the text cell for the column.

Thanks for everyone who stuck with me and tried help me on this. I hope this answer helps others in the future avoid several days of frustration like I just had!

Also as @Willeke points out, there's no real need to subclass the numberformatter if all you're doing is setting these properties. I'm going to do it because I have lots of cells that I want to share a common format but if all you're doing is formatting one cell, it's not needed.