我想在我的小应用程序中捕获关键事件。
我做了什么:
class ViewController : NSViewController { ... override func keyDown(theEvent: NSEvent) { if theEvent.keyCode == 124 { println("abc") } else { println("abcd") } } override var acceptsFirstResponder: Bool { return true } override func becomeFirstResponder() -> Bool { return true } override func resignFirstResponder() -> Bool { return true } ... }
怎么了:
按下某个键时,会播放Funk音效。
我看过很多帖子都在谈论这是一个属于NSView的委托,NSViewController没有访问权限。但是keydown函数覆盖自动完成类NSViewController类导致我认为这是错误的。
Xcode 8.2.1•Swift 3.0.2
原文链接:https://www.f2er.com/swift/320263.htmlimport Cocoa class ViewController: NSViewController { @IBOutlet var textField: NSTextField! override func viewDidLoad() { super.viewDidLoad() NSEvent.addLocalMonitorForEvents(matching: .flagsChanged) { self.flagsChanged(with: $0) return $0 } NSEvent.addLocalMonitorForEvents(matching: .keyDown) { self.keyDown(with: $0) return $0 } } override func keyDown(with event: NSEvent) { switch event.modifierFlags.intersection(.deviceIndependentFlagsMask) { case [.command] where event.characters == "l",[.command,.shift] where event.characters == "l": print("command-l or command-shift-l") default: break } textField.stringValue = "key = " + (event.charactersIgnoringModifiers ?? "") textField.stringValue += "\ncharacter = " + (event.characters ?? "") } override func flagsChanged(with event: NSEvent) { switch event.modifierFlags.intersection(.deviceIndependentFlagsMask) { case [.shift]: print("shift key is pressed") case [.control]: print("control key is pressed") case [.option] : print("option key is pressed") case [.command]: print("Command key is pressed") case [.control,.shift]: print("control-shift keys are pressed") case [.option,.shift]: print("option-shift keys are pressed") case [.command,.shift]: print("command-shift keys are pressed") case [.control,.option]: print("control-option keys are pressed") case [.control,.command]: print("control-command keys are pressed") case [.option,.command]: print("option-command keys are pressed") case [.shift,.control,.option]: print("shift-control-option keys are pressed") case [.shift,.command]: print("shift-control-command keys are pressed") case [.control,.option,.command]: print("control-option-command keys are pressed") case [.shift,.command,.option]: print("shift-command-option keys are pressed") case [.shift,.command]: print("shift-control-option-command keys are pressed") default: print("no modifier keys are pressed") } } }
要在按下字符键时摆脱呜呜声,需要对视图进行子类化,重写方法performKeyEquivalent并返回true。
import Cocoa class View: NSView { override func performKeyEquivalent(with event: NSEvent) -> Bool { return true } }