我目前有NSArray可以从mySQL数据库获取其数据。
我需要基于硬编码的字符串"Customer1"
以下是我到目前为止的内容:
import UIKit
class showCustomerDetails: UIViewController, UITableViewDataSource, UITableViewDelegate, FeedDetailProtocol {
var feedItems: NSArray = NSArray()
var selectedStock : DetailModel = DetailModel()
@IBOutlet weak var stockResultsFeed: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
self.stockResultsFeed.delegate = self
self.stockResultsFeed.dataSource = self
let detailModel = FeedDetail()
detailModel.delegate = self
detailModel.downloadItems()
}
func itemsDownloaded(items: NSArray) {
feedItems = items
self.stockResultsFeed.reloadData()
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// Return the number of feed items
return feedItems.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// Retrieve cell
let cellIdentifier: String = "customerDetails"
let myCell: UITableViewCell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier)!
myCell.textLabel?.textAlignment = .center
// Get the stock to be shown
let item: DetailModel = feedItems[indexPath.row] as! DetailModel
// Configure our cell title made up of name and price
let customerDetails = [item.code, item.manufacturer, item.model].compactMap { $0 }.joined(separator: " — ")
print(customerDetails)
// Get references to labels of cell
myCell.textLabel!.text = customerDetails
return myCell
}
}
以下是我的想法,但我不确定如何正确应用它:
let searchString = "Customer1"
let predicate = NSPredicate(format: "SELF contains %@", searchString)
let searchDataSource = feedItems.filter { predicate.evaluateWithObject($0) }
然后:
let item: DetailModel = searchDataSource[indexPath.row] as! DetailModel
NSArray数据来自:
import Foundation
protocol FeedDetailProtocol: class {
func itemsDownloaded(items: NSArray)
}
class FeedDetail: NSObject, URLSessionDataDelegate {
weak var delegate: FeedDetailProtocol!
let urlPath = "https://www.example.com/test1/test1.php"
func downloadItems() {
let url: URL = URL(string: urlPath)!
let defaultSession = Foundation.URLSession(configuration: URLSessionConfiguration.default)
let task = defaultSession.dataTask(with: url) { (data, response, error) in
if error != nil {
print("Error")
}else {
print("details downloaded")
self.parseJSON(data!)
}
}
task.resume()
}
func parseJSON(_ data:Data) {
var jsonResult = NSArray()
do{
jsonResult = try JSONSerialization.jsonObject(with: data, options:JSONSerialization.ReadingOptions.allowFragments) as! NSArray
} catch let error as NSError {
print(error)
}
var jsonElement = NSDictionary()
let stocks = NSMutableArray()
for i in 0 ..< jsonResult.count
{
jsonElement = jsonResult[i] as! NSDictionary
let stock = DetailModel()
//the following insures none of the JsonElement values are nil through optional binding
if let code = jsonElement[“code”] as? String,
let customer = jsonElement["customer"] as? String,
let manufacturer = jsonElement["manufacturer"] as? String,
let model = jsonElement["model"] as? String
{
print(code)
print(manufacturer)
print(model)
print(customer)
stock.code = code
stock.manufacturer = manufacturer
stock.model = model
stock.customer = customer
}
stocks.add(stock)
}
DispatchQueue.main.async(execute: { () -> Void in
self.delegate.itemsDownloaded(items: stocks)
})
}
}
答案 0 :(得分:0)
这是Swift。使用Array而非NSArray,只需调用Array的filter
方法即可。 NSArray属于Cocoa和Objective-C;您应尽可能使用本机Swift类型和Swift方法。
如果您坚持使用Cocoa Objective-C方法过滤NSArray,并且坚持使用NSPredicate,则最简单的方法是使用init(block:)
构成谓词。
这是一个简单的例子:
let arr = ["Manny", "Moe", "Jack"] as NSArray
let p = NSPredicate { element, _ in
return (element as? String)?.contains("a") ?? false
}
let arr2 = arr.filtered(using: p)
print(arr2) // [Manny, Jack]
但是(为了说明问题)在本机Swift中要简单得多:
let arr = ["Manny", "Moe", "Jack"]
let arr2 = arr.filter {$0.contains("a")}