application(_:delegateHandlesKey:)

Declaration

@MainActor optional func application(_ sender: NSApplication, delegateHandlesKey key: String) -> Bool

Parameters

• sender:

  The app object associated with the delegate.

• key:

  The key to be handled.

Return Value

true if your delegate handles the key or false if it does not.

Discussion

Implement this method and return true if your delegate handles the specified key, Your delegate must be able get or set the scriptable property or element that corresponds to that key. You need to handle only your app’s custom commands. The app already implements methods for each of the keys that it handles, where the method name matches the key.

For example, a scriptable app that doesn’t use Cocoa’s document-based app architecture can implement this method to supply its own document ordering. You want to do this because the standard app delegate expects to work with a document-based app. The TextEdit app (whose source is distributed with macOS developer tools) provides the following implementation:

return [key isEqualToString:@"orderedDocuments"];

TextEdit then implements the orderedDocuments method in its controller class to return an ordered list of documents. An app with its own window ordering might add a test for the key orderedWindows so that its delegate can provide its own version of orderedWindows.