IBDesignable UIButton子類

Question

我想實現一個簡單的IBDesignable UIButton子類。我希望能夠爲Interface Builder的每個控件狀態設置顏色。我知道這可能與IBInspectable關鍵字。在狀態屬性上使用KVO時，我遇到IB崩潰問題。 IBDesignable調試器在deinit時崩潰。有誰知道我可以如何與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, forKeyPath: "state", context: nil) 
    } 

} 

Answer 1

我有類似的東西

問題是init()方法，重構我的代碼它就像一個魅力後導致崩潰。也許它會幫助你：

#if !TARGET_INTERFACE_BUILDER 
required init(coder aDecoder: NSCoder) { 
    super.init(coder: aDecoder) 
    self._setup() 
} 
#endif 

override func prepareForInterfaceBuilder() { 
    self._setup() 
} 

Answer 2

對於的Xcode 7.2爲@IBDesignable UIButton Subclass常見的代碼如下所示：

import UIKit 

@IBDesignable class MyButton: UIButton { 

    //this init fires usually called, when storyboards UI objects created: 
    required init?(coder aDecoder: NSCoder) { 
     super.init(coder: aDecoder) 
     self.setupViews() 
    } 

    //This method is called during programmatic initialisation 
    override init(frame: CGRect) { 
     super.init(frame: frame) 
     setupViews() 
    } 


    func setupViews() { 
     //your common setup goes here 
    } 

    //required method to present changes in IB 
    override func prepareForInterfaceBuilder() { 
     super.prepareForInterfaceBuilder() 
     self.setupViews() 
    } 
}