我正在尝试实现一个IBDesignable的简单UIButton子类.我希望能够从Interface Builder为控件的每个状态设置颜色.我知道这可以通过IBInspectable关键字实现.我在状态属性上使用KVO时遇到IB崩溃问题. IBDesignable调试器在deinit上崩溃.有谁知道我如何与KVO和IBDesignable一起工作?
@IBDesignable class UIButtonActionButton: UIButton { @IBInspectable var defaultColour: UIColor = UIColor.blueColor() { didSet { self.setNeedsDisplay() } } @IBInspectable var selectedColour: UIColor = UIColor.blueColor() @IBInspectable var disabledColour: UIColor = UIColor.grayColor() required init(coder aDecoder: NSCoder) { super.init(coder: aDecoder) self._setup() } override init(frame: CGRect) { super.init(frame: frame) self._setup() } private func _setup(){ self.addObserver(self,forKeyPath: "state",options: NSKeyValueObservingOptions.New,context: nil) self.layer.cornerRadius = 5.0 self.layer.masksToBounds = true } override func observeValueForKeyPath(keyPath: String,ofObject object: AnyObject,change: [NSObject : AnyObject],context: UnsafeMutablePointer<Void>) { self.setNeedsDisplay() } override func drawRect(rect: CGRect) { super.drawRect(rect) let context = UIGraphicsGetCurrentContext() if self.highlighted { CGContextSetFillColorWithColor(context,selectedColour.CGColor) CGContextFillRect(context,self.bounds) } else if self.state == UIControlState.Disabled { CGContextSetFillColorWithColor(context,disabledColour.CGColor) CGContextFillRect(context,self.bounds) } else { CGContextSetFillColorWithColor(context,defaultColour.CGColor) CGContextFillRect(context,self.bounds) } } deinit { self.removeObserver(self,context: nil) } }