I'm working on an app with a custom file browser, and currently I'm working on implementing copy/paste. I have a button in the navigation bar that I've attached a UIMenu to, to reveal options on adding files, including pasting. I want to have the paste button automatically enable when files are in the clipboard, and disable when the clipboard's empty. I tried doing this at first:
// in class definition
var pasteAction: UIAction?
@IBOutlet var addButton: UIBarButtonItem!
// in viewDidLoad()
pasteAction = UIAction(
title: "Paste Files",
image: UIImage(systemName: "doc.on.clipboard"),
attributes: clipboard.isEmpty ? .disabled : [],
handler: pasteFiles
)
addButton.menu = UIMenu(
title: "", image: nil, identifier: nil, options: .displayInline,
children: [folder, file, imp, pasteAction!]
)
// in copy()
pasteAction!.attributes = clipboard.isEmpty ? .disabled : []
However, the paste button remained disabled. (When leaving and re-entering the view controller, the paste button is enabled.) I also tried replacing the menu with a new one with the same children:
pasteAction!.attributes = clipboard.isEmpty ? .disabled : []
var c = Array(addButton.menu!.children[0...2])
c.append(pasteAction!)
addButton.menu = addButton.menu!.replacingChildren(c)
This did not work either. Finally, I tried creating a new UIAction, just in case it's not actually possible to modify it:
var c = Array(addButton.menu!.children[0...2])
c.append(UIAction(
title: "Paste Files",
image: UIImage(systemName: "doc.on.clipboard"),
attributes: FilesViewController.clipboard.isEmpty ? .disabled : [],
handler: pasteFiles
))
addButton.menu = addButton.menu!.replacingChildren(c)
Yet this still doesn't do anything. Am I missing some update function I need to call? Or am I not able to modify the menu for a navigation bar button after loading the view?
