I'm using a custom item with menu in the system Status Bar for controlling some functions in my app. Here is my code:
import Foundation
class StatusBarMenuController {
var statusItem: NSStatusItem
init() {
self.statusItem = NSStatusBar.system().statusItem(withLength: NSSquareStatusItemLength)
statusItem.image = NSImage(named: "StatusBarButtonImage")
let menu = NSMenu()
let isListeningMenuItem = NSMenuItem(title: "Listening", action: #selector(StatusBarMenuController.isListeningAction(_:)), keyEquivalent: "")
isListeningMenuItem.isAlternate = true
isListeningMenuItem.target = self
isListeningMenuItem.state = NSOnState
menu.addItem(isListeningMenuItem)
statusItem.menu = menu
}
@objc func isListeningAction(_ item: NSMenuItem) {
if (item.state == NSOffState) {
item.state = NSOnState
// Handle switch-on action...
}
else {
item.state = NSOffState
// Handle switch-off action...
}
}
}
This class is instantiated in applicationDidFinishLaunching
method of AppDelegate
.
All works fine on the latest version of macOS (10.12) - I tried it on multiple computers, but when try to start the app on a machine with older version of os, e.g. OS X 10.11, it instantly crashes.
Crash details:
Application Specific Information: Unrecognized selector -[MyAppName.StatusBarMenuController methodForSelector:]
abort() called
Any ideas why is this happening?
Deriving from NSObject
solved this issue:
import Foundation
class StatusBarMenuController: NSObject {
var statusItem: NSStatusItem
override init() {
self.statusItem = NSStatusBar.system().statusItem(withLength: NSSquareStatusItemLength)
super.init()
statusItem.image = NSImage(named: "StatusBarButtonImage")
let menu = NSMenu()
let isListeningMenuItem = NSMenuItem(title: "Listening", action: #selector(StatusBarMenuController.isListeningAction(_:)), keyEquivalent: "")
isListeningMenuItem.isAlternate = true
isListeningMenuItem.target = self
isListeningMenuItem.state = NSOnState
menu.addItem(isListeningMenuItem)
statusItem.menu = menu
}
@objc func isListeningAction(_ item: NSMenuItem) {
if (item.state == NSOffState) {
item.state = NSOnState
// Handle switch-on action...
}
else {
item.state = NSOffState
// Handle switch-off action...
}
}
}
It's a very strange behavior, because in other parts of my app I'm using selectors with NotificationCenter
in not NSObject-derived classes and it works, e.g.:
class StatusBarMenuController {
NotificationCenter.default.addObserver(
self,
selector: #selector(handleMyNotification),
name: NSNotification.Name(rawValue: myNotification),
object: nil
)
@objc func handleMyNotifiction(_ notification: Notification) {
// ...
}
}