import UIKit
protocol VisitURLProtocol{
    func didVisitURL(url:String);
}

 var visitURLDelegate:VisitURLProtocol!;

//调用 
self.visitURLDelegate.didVisitURL(data.visitUrl as String);

class MessageViewController: UIViewController,VisitURLProtocol
{

}

//初始化的时候添加，即viewLoad方法内 
//tableView为第二步骤类的对象
self.tableView.visitURLDelegate = self

    func didVisitURL(url:String){
        
        print(url);
        
    }