• 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.airdrop3.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
  • 结语

    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