关于ios:iOS-MultipeerConnectivity

问题

承接上文 [iOS 实现 WIFI 传书]，如果去掉局域网会如何？是否实现设施间文件传输

iOS 设施间的数据传输罕用形式：

1. 蓝牙
2.airdrop
3.MultipeerConnectivity

该篇单讲 MultipeerConnectivity

上菜

设施作为服务端

• 要有一个标记本人的 PeerID

lazy var me: MCPeerID = {let peer = MCPeerID(displayName: UIDevice.current.name)
    return peer
}()

• 一个 session

lazy var session: MCSession = {let ss = MCSession(peer: me, securityIdentity: nil, encryptionPreference: .none)
    ss.delegate = self
    return ss
}()

• 播送进来，其余设施能力搜寻到

lazy var advertiser: MCNearbyServiceAdvertiser = {let advertiser = MCNearbyServiceAdvertiser(peer: me, discoveryInfo: ["demo": "data"], serviceType: "shanzhai")
    advertiser.delegate = self
    return advertiser
}()

• 开始播送

advertiser.startAdvertisingPeer()

• 播送的代理办法执行

extension MultipeerConnectVC: MCNearbyServiceAdvertiserDelegate {func advertiser(_ advertiser: MCNearbyServiceAdvertiser, didReceiveInvitationFromPeer peerID: MCPeerID, withContext context: Data?, invitationHandler: @escaping (Bool, MCSession?) -> Void) {
        // 确认连贯，赋值 session
        invitationHandler(true, session)
    }
    
    func advertiser(_ advertiser: MCNearbyServiceAdvertiser, didNotStartAdvertisingPeer error: Error) {advertiser.stopAdvertisingPeer()
        print("Woops! Advertising failed with error \(String(describing: error))")
    }
}

设施作为客户端

• 要有一个标记本人的 PeerID

lazy var me: MCPeerID = {let peer = MCPeerID(displayName: UIDevice.current.name)
    return peer
}()

• 一个 session

lazy var session: MCSession = {let ss = MCSession(peer: me, securityIdentity: nil, encryptionPreference: .none)
    ss.delegate = self
    return ss
}()

• 须要一个搜寻 PeerID

lazy var browser: MCNearbyServiceBrowser = {let bs = MCNearbyServiceBrowser(peer: me, serviceType: "shanzhai")
    bs.delegate = self
    return bs
}()

• 开始搜寻

browser.startBrowsingForPeers()

• 代理中检索到左近的 PeerID, 检索到能够本人存下来，也能够间接链接，依业务需要来，此处直连

extension MultipeerConnectVC: MCNearbyServiceBrowserDelegate {func browser(_ browser: MCNearbyServiceBrowser, foundPeer peerID: MCPeerID, withDiscoveryInfo info: [String : String]?) {print("search peerId = \(peerID)")
        // 搜到了 peerID 能够放入数组中，抉择想要连贯的 peerID 连贯，这里间接连贯
        browser.invitePeer(peerID, to: session, withContext: nil, timeout: 10)
    }
    
    func browser(_ browser: MCNearbyServiceBrowser, lostPeer peerID: MCPeerID) {print("lost peerID = \(peerID)")
    }
    
    func browser(_ browser: MCNearbyServiceBrowser, didNotStartBrowsingForPeers error: Error) {print("error = \(error)")
    }
}

连贯过程看 Session，session 代理中看各个过程

extension MultipeerConnectVC: MCSessionDelegate {func session(_ session: MCSession, peer peerID: MCPeerID, didChange state: MCSessionState) { }
    
    func session(_ session: MCSession, didReceive data: Data, fromPeer peerID: MCPeerID) { }
    
    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?) {}}

• 代理办法 didChange didChange 办法中 MCSessionState == .connected，示意连贯上，连贯上后可传递数据
• 代理办法 didFinishReceivingResourceWithName，能够查看接管到的数据
• 也可应用 MCBrowserViewController，搜寻到的 PeerID，无需本人写界面

该形式并未买通 iOS 与 Android，实用于苹果设施之间的无网络数据传输。FileChat 在苹果设施之间的实现形式应该是基于此进行的