Subclassing NSControl， IBAction 在 Swift 中不被调用

Question

我已经子类化了一个NSSlider，无论按下选项键，它的行为都不同。为了做到这一点，我覆盖了鼠标向下功能。它似乎可以完成这项工作。问题是，我注意到我的视图控制器中的连接@IBAction仅在未按下选项键时触发(即当 mouseDown 方法传递给 super(时。为了让@IBAction执行，我缺少什么？

非常感谢除了这个问题，欢迎对代码提出改进建议... ：-(

乔希

class ViewController: NSViewController {
    @IBOutlet weak var theSlider: MySlider!
    @IBAction func moveSlider(sender: NSSlider) {
        print(sender.floatValue) //works only with optionKey unpressed
    }
}
class MySlider: NSSlider { //Implemented in another source file
    @IBInspectable var multiplier: Float = 0.5
    private var modifierKeys = NSEventModifierFlags.AlternateKeyMask
    private var optionKeyPressed = false
    private var previousSliderPosition: Float = 0.0
//MARK: Init with NSCoder
    required init?(coder: NSCoder) {
        super.init(coder: coder)
        Swift.print("init Coder called")
        self.continuous = true
        NSEvent.addLocalMonitorForEventsMatchingMask(.FlagsChangedMask) { (theEvent) -> NSEvent? in
            self.flagsChanged(theEvent)
            return theEvent
        }
    }
//MARK: Mouse tracking
    override func mouseDown(theEvent: NSEvent) {
        if optionKeyPressed {
            var keepOn = true
            previousSliderPosition = self.floatValue * Float(self.bounds.width) / Float(self.maxValue)
            while keepOn {
                if let nextEvent = self.window?.nextEventMatchingMask(Int(NSEventMask.LeftMouseUpMask.rawValue) | Int(NSEventMask.LeftMouseDraggedMask.rawValue))
                {
                    switch nextEvent.type
                    {
                    case .LeftMouseDragged:
                         let mouseInnerLocationX = Float(self.convertPoint(nextEvent.locationInWindow, fromView: self.superview).x)
                        let mouseDelta = mouseInnerLocationX - previousSliderPosition
                        let newSliderPosition = previousSliderPosition + (mouseDelta) * multiplier
                        self.floatValue = newSliderPosition * Float(self.maxValue) / Float(self.bounds.width)
                        break
                    case .LeftMouseUp:
                        keepOn = false
                        break
                    default:
                        break
                    }
                }
            }
        } else {
            super.mouseDown(theEvent)
        }
    }
//MARK: Option key handling
    override func flagsChanged(theEvent: NSEvent) {
        if (theEvent.modifierFlags.rawValue & NSEventModifierFlags.DeviceIndependentModifierFlagsMask.rawValue) == NSEventModifierFlags.AlternateKeyMask.rawValue {
            optionKeyPressed = true
        } else {
            optionKeyPressed = false
        }
    }
}

Answer 1

如果您不调用super.mouseDown，则需要自己发送操作：

sendAction(action, to: target)

sendAction(_:to:)、action和target是NSControl的现有成员。