Swift WebView - 无连接模式[重复]

Posted 2023-03-22

【中文标题】Swift WebView - 无连接模式[重复]

【英文标题】：Swift WebView - No Connection Mode [duplicate]

【发布时间】：2015-05-11 15:40:32

【问题描述】：

我目前正在使用 UIWebView 显示来自 URL 的控制器内容，我想知道，如果没有与设备的连接，我怎么能显示一条消息或显示一个警报对话框，你需要互联网连接来显示内容？

我有以下代码：

import UIKit

class SecondView: UICollectionViewController 

    override func viewDidLoad() 
        super.viewDidLoad()
        let myWebView:UIWebView = UIWebView(frame: CGRectMake(0, 0, UIScreen.mainScreen().bounds.width, UIScreen.mainScreen().bounds.height))
        myWebView.loadRequest(NSURLRequest(URL: NSURL(string: "http://www.google.com")!))
        self.view.addSubview(myWebView)
    

    override func didReceiveMemoryWarning() 
        super.didReceiveMemoryWarning()
    

谢谢！

【参考方案1】：

这里是完整的工作代码：

import UIKit
import Foundation
import SystemConfiguration

public class Reachability 

class func isConnectedToNetwork() -> Bool 

    var zeroAddress = sockaddr_in(sin_len: 0, sin_family: 0, sin_port: 0, sin_addr: in_addr(s_addr: 0), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))
    zeroAddress.sin_len = UInt8(sizeofValue(zeroAddress))
    zeroAddress.sin_family = sa_family_t(AF_INET)

    let defaultRouteReachability = withUnsafePointer(&zeroAddress) 
        SCNetworkReachabilityCreateWithAddress(nil, UnsafePointer($0)).takeRetainedValue()
    

    var flags: SCNetworkReachabilityFlags = 0
    if SCNetworkReachabilityGetFlags(defaultRouteReachability, &flags) == 0 
        return false
    

    let isReachable = (flags & UInt32(kSCNetworkFlagsReachable)) != 0
    let needsConnection = (flags & UInt32(kSCNetworkFlagsConnectionRequired)) != 0

    return (isReachable && !needsConnection) ? true : false





class SecondView: UICollectionViewController 

override func viewDidLoad() 
    super.viewDidLoad()




override func viewDidAppear(animated: Bool) 
    if Reachability.isConnectedToNetwork() 

        let myWebView:UIWebView = UIWebView(frame: CGRectMake(0, 0, UIScreen.mainScreen().bounds.width, UIScreen.mainScreen().bounds.height))
        myWebView.loadRequest(NSURLRequest(URL: NSURL(string: "http://www.google.com")!))
        self.view.addSubview(myWebView)

     else 

        var alert = UIAlertController(title: "Alert", message: "you need internet connection to display the content", preferredStyle: UIAlertControllerStyle.Alert)
        alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
        
    

【讨论】：

它没有给出错误，但应用程序崩溃了。我将 Foundation & SystemConfiguration 添加到“链接框架和库”中......

显示你的崩溃日志

您是否更改了我代码中的类名？我更新了答案中的班级名称，检查一下。

很高兴为您提供帮助。:)