ios - 如何从 Swift 中的另一个类重新加载 Collection View Cells

Question

我尝试在接收到一些 BLE 数据时重新加载 CollectionView。这是我的 BluetoothManager 类:

import UIKit
import CoreBluetooth

class BluetoothManager: NSObject, CBCentralManagerDelegate, CBPeripheralDelegate {
static var bluetoothManager = BluetoothManager()
...
var Value: [String] = [""]
...
func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?){
//For this example, there is only a string value to update
Value[0] = "It works!"
}}

一切正常，当我收到一些数据时，didUpdateValueForCharacteristic 函数被调用，Value 数组的第一项是字符串“It works”。现在我想刷新/重新加载我的 CollectionView Controller ，以显示新值。这是我的收藏 View 类:

import UIKit

class ValueCollectionView: UICollectionViewController{
    @IBOutlet var ValueCollectionView: UICollectionView!

    var valueCollectionViewCell: ValueCollectionViewCell = ValueCollectionViewCell()

    override func viewDidLoad()
    {
        super.viewDidLoad()
    }

    override func didReceiveMemoryWarning()
    {
        super.didReceiveMemoryWarning()
    }

    override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
    {
        return BluetoothManager.bluetoothManager.Value.count
    }

    override func collectionView(tableView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
    {
        let cell: ValueCollectionViewCell = collectionView?.dequeueReusableCellWithReuseIdentifier("valueCell", forIndexPath: indexPath) as! ValueCollectionViewCell
        cell.ValueCollectionViewLabel.text = BluetoothManager.bluetoothManager.Value[indexPath.row]
        return cell
    }
}

我必须在我的 BluetoothManager 类中添加什么才能重新加载 CollectionView？我想到了类似的东西:ValueCollectionView.reloadData() 但我不知道如何实现它。谢谢!

Answer 1

试试这个:

import UIKit
import CoreBluetooth

class BluetoothManager: NSObject, CBCentralManagerDelegate, CBPeripheralDelegate {
static var bluetoothManager = BluetoothManager()
...
var ValueCollectionView: UICollectionView? 
var Value: [String] = [""]
...
func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?){
//For this example, there is only a string value to update
Value[0] = "It works!"
ValueCollectionView?.reloadData()
}}

和

import UIKit

class ValueCollectionView: UICollectionViewController{
    @IBOutlet var ValueCollectionView: UICollectionView!

    var valueCollectionViewCell: ValueCollectionViewCell = ValueCollectionViewCell()

    override func viewDidLoad()
    {
        super.viewDidLoad()
        BluetoothManager.bluetoothManager.ValueCollectionView = ValueCollectionView
    }

    override func didReceiveMemoryWarning()
    {
        super.didReceiveMemoryWarning()
    }

    override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
    {
        return BluetoothManager.bluetoothManager.Value.count
    }

    override func collectionView(tableView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
    {
        let cell: ValueCollectionViewCell = collectionView?.dequeueReusableCellWithReuseIdentifier("valueCell", forIndexPath: indexPath) as! ValueCollectionViewCell
        cell.ValueCollectionViewLabel.text = BluetoothManager.bluetoothManager.Value[indexPath.row]
        return cell
    }
}