多点连接 - 如何查看找到的设备答案

【问题标题】：Multipeer connectivity- how to view the found devices多点连接 - 如何查看找到的设备
【发布时间】：2017-12-20 20:40:35
【问题描述】：

我在 Swift 4 中使用 Multipeer Connectivity，我想知道如何在程序运行时查看找到的设备，我得到了一点帮助，但我还是不太明白。我也不知道该放在哪里：

extension viewcontroller : MCBrowserViewControllerDelegate {
func browserViewControllerDidFinish(_ browserViewController:                         
MCBrowserViewController) {
serviceBrowser.dismiss(animated: true, completion: nil)
}
func browserViewControllerWasCancelled(_ browserViewController:   
MCBrowserViewController) {
serviceBrowser.dismiss(animated: true, completion: nil)
}

}

这是我的完整代码，如果需要请更正任何代码，我还将扩展名放在下面代码的底部：

import UIKit
import PlaygroundSupport
import MultipeerConnectivity
PlaygroundPage.current.needsIndefiniteExecution = true
var peerID: MCPeerID!
var mcSession: MCSession!
var mcAdvertiserAssistant: MCAdvertiserAssistant!
var foundPeers = [MCPeerID]()


class viewcontroller: UIViewController {
override func viewDidLoad() {
    var serviceBrowser : MCBrowserViewController!
    func startBrowsingForPeer()  {
        serviceBrowser = MCBrowserViewController(serviceType: "lightning417techa", session: mcSession)

        serviceBrowser.delegate.self

    }



    peerID = MCPeerID(displayName: UIDevice.current.name)
    mcSession = MCSession(peer: peerID, securityIdentity: nil, encryptionPreference: .none)
    mcSession.delegate.self

    class ViewController: UIViewController, MCSessionDelegate, MCBrowserViewControllerDelegate {



        let session = MCSession(peer: peerID, 
                                securityIdentity: nil, 
                                encryptionPreference: .none)



        func session(_ session: MCSession, peer peerID: MCPeerID, didChange state: MCSessionState) {
            switch state {
            case MCSessionState.connected:
                print("Connected: \(peerID.displayName)")
            case MCSessionState.connecting:
                print("Connecting: \(peerID.displayName)")
            case MCSessionState.notConnected:
                print("Not Connected: \(peerID.displayName)")
            }
        }

        func browser(browser: MCNearbyServiceBrowser!, foundPeer peerID: MCPeerID!, withDiscoveryInfo info: [NSObject : AnyObject]!) {
            foundPeers.append(peerID)

            print(browser)
        }


        func session(_ session: MCSession, didReceive data: Data, fromPeer peerID: MCPeerID) {
            if let image = UIImage(data: data) {
                DispatchQueue.main.async { [unowned self] in
                    print("image recieved")
                }
            }
        }
        func sendImage(img: UIImage) {
            if mcSession.connectedPeers.count > 0 {
                if let imageData = UIImagePNGRepresentation(img) {
                    do {
                        try mcSession.send(imageData, toPeers: mcSession.connectedPeers, with: .reliable)
                    } catch let error as NSError {
                        let ac = UIAlertController(title: "Send error", message: error.localizedDescription, preferredStyle: .alert)
                        ac.addAction(UIAlertAction(title: "OK", style: .default))
                        present(ac, animated: true)
                    }
                }
            }
        }

        func session(_ session: MCSession, didReceive stream: InputStream, withName streamName: String, fromPeer peerID: MCPeerID) {
        }
        func session(_ session: MCSession, didStartReceivingResourceWithName resourceName: String, fromPeer peerID: MCPeerID, with progress: Progress) {
        }
        func session(_ session: MCSession, didFinishReceivingResourceWithName resourceName: String, fromPeer peerID: MCPeerID, at localURL: URL?, withError error: Error?) {
        }
        func browserViewControllerDidFinish(_ browserViewController: MCBrowserViewController) {
            dismiss(animated: true)
        }
        func browserViewControllerWasCancelled(_ browserViewController: MCBrowserViewController) {
            dismiss(animated: true)
        }


        func startHosting(action: UIAlertAction!) {
            mcAdvertiserAssistant = MCAdvertiserAssistant(serviceType: "hws-ridleyn", discoveryInfo: nil, session: mcSession)
            mcAdvertiserAssistant.start()
        }
        func joinSession(action: UIAlertAction!) {
            let mcBrowser = MCBrowserViewController(serviceType: "hws-ridleyn", session: mcSession)
            mcBrowser.delegate = self
            present(mcBrowser, animated: true)
        }

        let vc = UIToolbar(frame: CGRect(x: 100, y: 100, width: 200, height: 200))


        // your view controller here
    }


    let vcc = ViewController()
    vcc.startHosting(action: nil)
    ViewController.startHosting(vcc)

    }
}



PlaygroundPage.current

extension viewcontroller : MCBrowserViewControllerDelegate {
func browserViewControllerDidFinish(_ browserViewController:    MCBrowserViewController) {          
serviceBrowser.dismiss(animated: true, completion: nil)
}
func browserViewControllerWasCancelled(_ browserViewController: MCBrowserViewController) {
serviceBrowser.dismiss(animated: true, completion: nil)
}

}

我刚刚编辑了扩展，但它说serviceBrowser不知何故不正确，它想用NetServiceBrowser 替换它。所以当我这样做的时候，NetServiceBrowser 没有成员 dismiss。

【问题讨论】：

标签： ios swift swift3 swift4 multipeer-connectivity

【解决方案1】：

MCSession 包含一个名为 connectedPeers 的变量。

var connectedPeers: [MCPeerID] 当前连接到此会话的所有对等方的数组。

见Apple documentation - MCSession class

【讨论】：

【解决方案2】：

如果它是您需要的已找到对等点的列表，请将存储的属性修改为

var foundPeers = [MCPeerID]() {
    didSet {
        let peers = foundPeers.map( {$0.displayName} )
        yourFoundPeerLabel.text = String(format: "Found Peers: %@", peers.joined(separator: ", "))
    }
}

每次找到设备时都会更新 storedProperty，并且当新的对等方附加到列表时，您的标签将自动更新。请参考您的委托方法的实现

func browser(browser: MCNearbyServiceBrowser!, foundPeer peerID: MCPeerID!, withDiscoveryInfo info: [NSObject : AnyObject]!);

PS：如果你需要连接设备的列表，创建一个类似的存储属性并使用委托方法

func session(_ session: MCSession, peer peerID: MCPeerID, didChange state: MCSessionState);

将设备添加到列表中。逻辑保持不变。

【讨论】：