Swift中的Objective C Setter覆盖

  
本文介绍了Swift中的Objective C Setter覆盖的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我需要在我的自定义 UIButton 子类中覆盖 UIViews 高亮属性的设置器；

I need to override the setter of UIViews highlighted property in my custom UIButton subclass ;

目标 C

@property(nonatomic,getter=isHighlighted) BOOL highlighted;

像这样被覆盖

- (void) setHighlighted:(BOOL)highlighted {
    [super setHighlighted:highlighted];

    if (highlighted) {
        self.backgroundColor = UIColorFromRGB(0x387038);
    }
    else {
        self.backgroundColor = UIColorFromRGB(0x5bb75b);
    }

   [super setHighlighted:highlighted];

}

斯威夫特

var highlighted: Bool

我试过了:

var highlighted: Bool {

   get{ return false }

   set {

        if highlighted {

       self.backgroundColor = UIColor.whiteColor() 
       //Error "Use unresolved identifier     'self'"

         I can't set the background color from value type in here 
        , can't call self.backgroundColor in this value type , 
         can't call super too because this is a value type , doesn't work 
        }

        }

   }

在 Swift 中应该如何以及在何处实现此方法以获得相同的结果.有什么想法吗?

How and where should implement this method in Swift to get the same result . any idea?

推荐答案

在 Swift 中，上面的解决方案对我有用，但我不得不省略 Bool= 真:

In Swift the solution above worked for me, but I had to omit the Bool = true:

import UIKit

class CustomUIButtonForUIToolbar: UIButton {

    // Only override drawRect: if you perform custom drawing.
    // An empty implementation adversely affects performance during animation.
    override func drawRect(rect: CGRect) {
        // Drawing code
        super.drawRect(rect)

        self.layer.borderColor = UIColor.blueColor().CGColor
        self.layer.borderWidth = 1.0
        self.layer.cornerRadius = 5.0
        self.clipsToBounds = true
        self.setTitleColor(UIColor.blueColor(), forState: UIControlState.Normal)

        self.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Highlighted)
    }

    override var highlighted: Bool {
        didSet {

            if (highlighted) {
                self.backgroundColor = UIColor.blueColor()
            }
            else {
                self.backgroundColor = UIColor.clearColor()
            }

        }
    }

}

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