//    var toolbar: NSToolbar? lazy var toolbar: NSToolbar = { let toolbar = NSToolbar (identifier: "ScreenNameToolbarIdentifier" )         toolbar.allowsUserCustomization = true toolbar.delegate = self return toolbar let toolbarItems: [[ String : String ]] = [         [ "title" : "irrelevant :)" , "icon" : "" , "identifier" : "NavigationGroupToolbarItem" ],         [ "title" : "Share" , "icon" : NSImage .shareTemplateName, "identifier" : "ShareToolbarItem" ],         [ "title" : "Add" , "icon" : NSImage .addTemplateName, "identifier" : "AddToolbarItem" ],         [ "title" : "Departments" , "icon" : "NSPreferencesGeneral" , "identifier" : "DepartmentViewController" ],         [ "title" : "Accounts" , "icon" : "NSFontPanel" , "identifier" : "AccountViewController" ],         [ "title" : "Employees" , "icon" : "NSAdvanced" , "identifier" : "EmployeeViewController" ],         [ "title" : "" , "icon" : "" , "identifier" : "NNUserInfoView" ], var toolbarTabsIdentifiers: [ NSToolbarItem . Identifier ] { var list = toolbarItems.compactMap { $0 [ "identifier" ] }.map{ NSToolbarItem . Identifier (rawValue: $0 ) }         list.insert( NSToolbarItem . Identifier .flexibleSpace, at: 3 )         list.insert( NSToolbarItem . Identifier .flexibleSpace, at: list.count - 1 ) //        list.append(NSToolbarItem.Identifier.flexibleSpace) return list var currentVC: NSViewController ! var currentIdentifier = "" // **MARK: -lifecycle** override init ( window : NSWindow ?) { super . init (window: window) //        toolbar = NSToolbar(identifier:"ScreenNameToolbarIdentifier") //        toolbar?.displayMode = .iconAndLabel //        toolbar?.allowsUserCustomization = true //        toolbar?.delegate = self window ? .toolbar = toolbar required init? ( coder : NSCoder ) { fatalError ( "init(coder:) has not been implemented" ) override func windowDidLoad () { super .windowDidLoad() // Do view setup here. // **MARK: -funtions** @objc func handleSegmentSelected ( _ sender : NSSegmentedControl ){ print ( " \( #function ) : \(sender.selectedSegment) " ) @objc func handleBtnSelected ( _ sender : NSButton ){ print ( " \( #function ) : \(sender) " ) @objc func handleItemSelected ( _ sender : NSToolbarItem ){ print ( " \( #function ) : \(sender.itemIdentifier.rawValue) _ \(sender.label) " )         loadViewWithIdentifier(itemIdentifier: sender.itemIdentifier.rawValue, withAnimation: true ) @objc func handleViewSelected ( _ sender : NNUserInfoView ){ print ( " \( #function ) : \(sender) " ) func loadViewWithIdentifier ( itemIdentifier : String , withAnimation shouldAnimate : Bool ){ let VCIdentifiers : [ String ] = [ "DepartmentViewController" , "AccountViewController" , "EmployeeViewController" ] if VCIdentifiers .contains(itemIdentifier) == false { return //        print("\(#function):\(itemIdentifier)") if (currentIdentifier == itemIdentifier){ return currentIdentifier = itemIdentifier guard let itemDict: [ String : String ] = toolbarItems.filter({ $0 [ "identifier" ] == itemIdentifier }).first else { return } if (itemIdentifier == "DepartmentViewController" ){             currentVC = DepartmentViewController () else if (itemIdentifier == "AccountViewController" ){             currentVC = AccountViewController () else if (itemIdentifier == "EmployeeViewController" ){             currentVC = EmployeeViewController () guard let window = self .window else { return } //        print(currentVC as Any) let newView = currentVC.view let windowRect = window.frame let currentViewRect = newView.frame //        print(windowRect as Any) let originY = windowRect.origin.y + (windowRect.size.height - currentViewRect.size.height) let newFrame = NSMakeRect (windowRect.origin.x, originY, currentViewRect.size.width, currentViewRect.size.height)         window.title = currentVC.title ?? itemDict[ "title" ] ! ;         window.contentView = newView         window.setFrame(newFrame, display: true , animate: shouldAnimate) lazy var popover: NSPopover = { let controller = ListViewController ()         controller.preferredContentSize = CGSize (width: kScreenWidth * 0.15 , height: kScreenHeight * 0.25 ) let popView = NSPopover (vc: controller) return popView func showPopoverController ( _ sender : NSView ) {         popover.show(sender, preferredEdge: .maxY) extension NNTabViewController : NSToolbarDelegate { func toolbar ( _ toolbar : NSToolbar , itemForItemIdentifier itemIdentifier : NSToolbarItem . Identifier , willBeInsertedIntoToolbar flag : Bool ) -> NSToolbarItem ? { guard let itemDict: [ String : String ] = toolbarItems.filter({ $0 [ "identifier" ] == itemIdentifier.rawValue }).first else { return nil } let toolbarItem: NSToolbarItem if itemIdentifier.rawValue == "NavigationGroupToolbarItem" { let group = NSToolbarItemGroup (itemIdentifier: itemIdentifier) let itemA = NSToolbarItem (itemIdentifier: NSToolbarItem . Identifier (rawValue: "PrevToolbarItem" ))             itemA.label = "Prev" let itemB = NSToolbarItem (itemIdentifier: NSToolbarItem . Identifier (rawValue: "NextToolbarItem" ))             itemB.label = "Next" //            let segmented = NSSegmentedControl(frame: NSRect(x: 0, y: 0, width: 85, height: 40)) //            segmented.segmentStyle = .texturedRounded //            segmented.trackingMode = .momentary //            segmented.segmentCount = 2 //            // Don't set a label: these would appear inside the button //            segmented.setImage(NSImage(named: NSImage.goBackTemplateName)!, forSegment: 0) //            segmented.setWidth(40, forSegment: 0) //            segmented.setImage(NSImage(named: NSImage.goForwardTemplateName)!, forSegment: 1) //            segmented.setWidth(40, forSegment: 1) let items: [ Any ] = [ NSImage (named: NSImage .goBackTemplateName) ! , NSImage (named: NSImage .goForwardTemplateName) ! , ] let segmented = NSSegmentedControl .create( NSRect (x: 0 , y: 0 , width: items.count * 40 , height: 40 ), items: items)             segmented.target = self segmented.action = #selector (handleSegmentSelected( _ :)) // `group.label` would overwrite segment labels group.paletteLabel = "Navigation" group.subitems = [itemA, itemB]             group.view = segmented             toolbarItem = group         } else if [ "ShareToolbarItem" , "AddToolbarItem" ].contains(itemIdentifier.rawValue) { let iconImage = NSImage (named: itemDict[ "icon" ] ! ) let button = NSButton (frame: NSRect (x: 0 , y: 0 , width: 40 , height: 40 ))             button.title = "" button.image = iconImage             button.bezelStyle = .texturedRounded             button.target = self //            button.action = #selector(handleBtnSelected(_:)) button.action = Selector (( "handleBtnSelected:" ))             toolbarItem = NSToolbarItem (itemIdentifier: itemIdentifier)             toolbarItem.label = itemDict[ "title" ] ! toolbarItem.view = button         } else if [ "NNUserInfoView" , ].contains(itemIdentifier.rawValue) { let userView = NNUserInfoView (frame: NSRect (x: 0 , y: 0 , width: 160 , height: 50 ))             userView.name = "SoaringHeart" userView.desc = "装逼或者被装逼。" userView.delegate = self toolbarItem = NSToolbarItem (itemIdentifier: itemIdentifier)             toolbarItem.label = itemDict[ "title" ] ! toolbarItem.target = self toolbarItem.action = #selector (handleViewSelected( _ :))             toolbarItem.view = userView         } else { let iconImage = NSImage (named: itemDict[ "icon" ] ! )             toolbarItem = NSToolbarItem (itemIdentifier: itemIdentifier)             toolbarItem.label = itemDict[ "title" ] ! toolbarItem.image = iconImage             toolbarItem.target = self toolbarItem.action = #selector (handleItemSelected( _ :)) return toolbarItem func toolbarDefaultItemIdentifiers ( _ toolbar : NSToolbar ) -> [ NSToolbarItem . Identifier ] { return self .toolbarTabsIdentifiers; func toolbarAllowedItemIdentifiers ( _ toolbar : NSToolbar ) -> [ NSToolbarItem . Identifier ] { return self .toolbarDefaultItemIdentifiers(toolbar) func toolbarSelectableItemIdentifiers ( _ toolbar : NSToolbar ) -> [ NSToolbarItem . Identifier ] { return self .toolbarDefaultItemIdentifiers(toolbar) func toolbarWillAddItem ( _ notification : Notification ) { print ( "toolbarWillAddItem" , (notification.userInfo ? [ "item" ] as? NSToolbarItem ) ? .itemIdentifier ?? "" ) func toolbarDidRemoveItem ( _ notification : Notification ) { print ( "toolbarDidRemoveItem" , (notification.userInfo ? [ "item" ] as? NSToolbarItem ) ? .itemIdentifier ?? "" ) extension NNTabViewController : NSToolbarItemValidation { func validateToolbarItem ( _ item : NSToolbarItem ) -> Bool { return true extension NNTabViewController : NNUserInfoViewDelegate { func userInfoView ( _ userView : NNUserInfoView , state : NSResponder . MouseState , event : NSEvent ) { switch state { case .entered: print ( " \( #function ) :进入区域" )             showPopoverController(userView) case .exited: print ( " \( #function ) :离开区域" ) case .down: print ( " \( #function ) :点击" ) case .up: print ( " \( #function ) :抬起" ) default : break

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