loadNibNamed的使用

原来-(id)init{
    self = [[[NSBundle mainBundle] loadNibNamed:@"ViewBtnWishList" owner:0 options:nil]     objectAtIndex:0];
return self;
}

swift
extension UIView {
    class func loadFromNibNamed(nibNamed: String, bundle : NSBundle = NSBundle.mainBundle()) -> UIView! {
        return UINib(nibName: nibNamed, bundle: bundle).instantiateWithOwner(nil, options: nil)[0] as? UIView
    }
}