某些時候，我們需要調(diào)整文字的顯示范圍（比如使用Label自定義提示語）已更美觀的時候,最簡單的方法就是繼承UIlabel后重寫UILable的相關(guān)方法；這里寫swift的實現(xiàn)版本，OC的實現(xiàn)類似
首先我們需要一個新建的UIEdgeInsets屬性，以及重新構(gòu)造init方法

var edgesInset : UIEdgeInsets?
    
    override init(frame: CGRect) {
        super.init(frame: frame);
        self.edgesInset = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
        
    }

    override func awakeFromNib() {
        super.awakeFromNib()
        self.edgesInset = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    

接著重寫他的rect范圍

    override func textRect(forBounds bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
        var rect = super.textRect(forBounds: UIEdgeInsetsInsetRect(bounds, self.edgesInset!), limitedToNumberOfLines: numberOfLines)
        rect.origin.x = rect.origin.x - (self.edgesInset?.left)!
        rect.origin.y = rect.origin.y - (self.edgesInset?.top)!
        rect.size.width = rect.size.width + (self.edgesInset?.left)! + (self.edgesInset?.right)!
        rect.size.height = rect.size.height + (self.edgesInset?.top)! + (self.edgesInset?.bottom)!

        return rect
        
    }

最后自然是重繪文字的顯示范圍

override func drawText(in rect: CGRect) {
        super.drawText(in: UIEdgeInsetsInsetRect(rect, self.edgesInset!))
    }

ok,這就搞定了，之所以重新定制Label的文字范圍，是因為要寫一個通用的提示，依托于snp就可以很輕易的實現(xiàn)，而不需要去引入第三方庫