在使用应用程序期间失去可达性连接时弹出警报（IOS xcode swift）

Question

我是IOS应用程序开发的初学者，想“在使用应用程序（IOS xcode swift）期间失去可达性连接时弹出警报”， 但我只有在启动我的应用程序时才会收到弹出警报。当互联网连接丢失时，在使用我的应用程序期间没有弹出警报。请大家帮忙，谢谢！

我做了什么： 1) 创建一个 Reachability.swift 文件并写入

import Foundation

public class Reachability {

class func isConnectedToNetwork()->Bool{

    var Status:Bool = false

    let url = NSURL(string: "http://google.com/")

    let request = NSMutableURLRequest(URL: url!)

    request.HTTPMethod = "HEAD"
    request.cachePolicy = NSURLRequestCachePolicy.ReloadIgnoringLocalAndRemoteCacheData
    request.timeoutInterval = 10.0        

    var response: NSURLResponse?

    var data = NSURLConnection.sendSynchronousRequest(request, returningResponse: &response, error: nil) as NSData?

    if let httpResponse = response as? NSHTTPURLResponse {

        if httpResponse.statusCode == 200 {
            Status = true
        }
    }

    return Status
 }
 }

2) 编辑 ViewController.swift 文件如下

import UIKit
class ViewController: UIViewController {

@IBOutlet weak var WebView: UIWebView!

//ViewDidLoad method
override func viewDidLoad() {
    super.viewDidLoad()

    if Reachability.isConnectedToNetwork() == true {
        println("Internet connection OK")
    } else {
        println("Internet connection FAILED")
        var alert = UIAlertView(title: "No Internet Connection",
                                message: "Make sure your device is connected to the internet.", 
                                delegate: nil, 
                                cancelButtonTitle: "OK")

        alert.show()

    }
    var URL = NSURL(string: "http://www.google.com/")

    WebView.loadRequest(NSURLRequest(URL: URL!))
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}

}

Answer 1

试试这个Reachabilty 类，将它添加到您的项目中，然后在您的viewController 中执行以下操作

let reachability = Reachability.reachabilityForInternetConnection()

reachability.whenReachable = { reachability in
if reachability.isReachableViaWiFi() {
 let alertController = UIAlertController(title: "Alert", message: "Reachable via WiFi", preferredStyle: .Alert)

    let defaultAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
    alertController.addAction(defaultAction)

    presentViewController(alertController, animated: true, completion: nil)

} 
else {
let alertController = UIAlertController(title: "Alert", message: "Reachable via Cellular", preferredStyle: .Alert)

    let defaultAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
    alertController.addAction(defaultAction)

    presentViewController(alertController, animated: true, completion: nil)
    }
  }
reachability.whenUnreachable = { reachability in
let alertController = UIAlertController(title: "Alert", message: "Not Reachable", preferredStyle: .Alert)

    let defaultAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
    alertController.addAction(defaultAction)

    presentViewController(alertController, animated: true, completion: nil)
}

reachability.startNotifier()