Swift 3：UITableViewCell更新RSSI

Question

执行扫描后，我有UITableView列表CBPeripheral。当您点击该行时，该应用将连接到CBPeripheral，Destination视图一旦连接就会显示CBPeripheral。

Destination视图是另一个UITableView，其中包含CBService列表。在此视图中，我有一个自定义标题，其中包含有关CBPeripheral的信息。我想更新该自定义标题单元格上的RSSI标签，而不必tableView.reloadData()。

我尝试在单元格中添加peripheral.readRSSI()，但代理peripheral(peripheral:didReadRSSI:error)似乎永远不会被调用。

我做错了什么？这可不是这样做的吗？

任何帮助表示感谢。

目的地视图

import UIKit
import CoreBluetooth

class ServicesTableViewController: UITableViewController, CBPeripheralDelegate {
    var peripheral: Peripheral?
    var sectionHeaderHeight: CGFloat = 110

    override func viewDidLoad() {
        super.viewDidLoad()
        if let peripheral = peripheral {
            peripheral.delegate = self
            peripheral.readRSSI()
            peripheral.discoverServices(nil)
        }
    }

    // MARK: - Table View

    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return peripheral?.services?.count ?? 0
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        guard let services = peripheral?.services else {
            return UITableViewCell()
        }

        let cell = tableView.dequeueReusableCell(withIdentifier: "ServiceTableViewCell", for: indexPath)

        let service = services[indexPath.row]
        cell.textLabel!.text = service.uuid.description
        cell.detailTextLabel?.text = service.uuid.uuidString
        return cell
    }

    override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        // Return false if you do not want the specified item to be editable.
        return false
    }

    override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
        let cell = tableView.dequeueReusableCell(withIdentifier: "ServiceHeaderTableViewCell") as! PeripheralTableViewCell

        if let peripheral = peripheral {
            cell.setupWithPeripheral(peripheral: peripheral)
        }

        return cell
    }

    override func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
        return sectionHeaderHeight
    }

    // MARK: - Peripheral Delegate

    func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
        print("Did discover services")

        if let error = error {
            print("Error: \(error)")
        } else {
            print("Discovered service:\n \(String(describing: peripheral.services))")
            tableView.reloadData()
        }
    }

PeripheralTableViewCell

import UIKit
import CoreBluetooth

class PeripheralTableViewCell: UITableViewCell, CBPeripheralDelegate {

    @IBOutlet weak var NameLabel: UILabel!
    @IBOutlet weak var UUIDLabel: UILabel!
    @IBOutlet weak var RSSILabel: UILabel!

    func setupWithPeripheral(peripheral: Peripheral) {
        NameLabel.text = peripheral.name ?? "No name"
        UUIDLabel.text = peripheral.identifier.uuidString

        if peripheral.state == .connected {
            print("Is connected... attempt to read RSSI")
            peripheral.readRSSI()
        }
    }

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }

    // MARK: - Peripheral Delegate

    func peripheral(_ peripheral: CBPeripheral, didReadRSSI RSSI: NSNumber, error: Error?) {
        print("Did read RSSI")

        if let error = error {
            print("Error: \(error)")
        } else {
            print("RSSI: \(RSSI)")
            RSSILabel.text = RSSI.stringValue

            if peripheral.state == .connected {
                //peripheral.readRSSI() \\ turn this into a timed call
            } else {
            }
        }
    }

}