[英]searching and filter array firebase data swift3
我的應用程序在搜索欄中搜索錯誤時出錯,該文本出現錯誤:thread1:signal SIGABRT可能是問題updateSearchResults()方法? 或數組類型? 我是個初學者,有什么想法嗎?
@IBOutlet weak var tableView: UITableView!
var data = [Any]()
var ref:FIRDatabaseReference!
// Filter Data from Firebase
var filteredData = [Any]()
// Declare searchBar
let searchController = UISearchController(searchResultsController: nil)
//is the device landscape or portrait
var isPortraid = true
@IBOutlet weak var bannerView: GADBannerView!
func fetchDataFromFirebase(){
EZLoadingActivity.show("caricamento...", disableUI: true)
ref = FIRDatabase.database().reference()
ref.observe(.value, with: { (snapshot) in
let dataDict = snapshot.value as! NSDictionary
self.data = dataDict["data"] as! [Any]
self.filteredData = self.data
print ("Sacco di merda:\(self.filteredData)")
self.tableView.reloadData()
EZLoadingActivity.hide()
})
}
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
fetchDataFromFirebase()
// Implement searchBar
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
definesPresentationContext = true
tableView.tableHeaderView = searchController.searchBar
NotificationCenter.default.addObserver(self, selector: #selector(MainViewController.orientationChanged), name: NSNotification.Name.UIDeviceOrientationDidChange, object: nil)
}
//TableView Data Source and Delegate
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return filteredData.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "MainCell", for:indexPath) as! MainScreenTableViewCell
let rowData = self.filteredData[indexPath.row] as! NSDictionary
let imageName = rowData["imageName"] as! String
cell.backgroundImageView.image = UIImage(named: imageName)
let label = rowData["categoryName"] as! String
cell.mealCategoryLabel.text = label
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let storyboard = UIStoryboard(name: "Main", bundle: Bundle.main)
let categoryViewController = storyboard.instantiateViewController(withIdentifier: "CategoryViewController") as! CategoryViewController
let rowData = self.data[indexPath.row] as! NSDictionary
categoryViewController.categoryTitle = rowData["categoryName"] as! String
let categoryData = rowData["category"] as! [Any]
categoryViewController.data = categoryData
self.navigationController?.pushViewController(categoryViewController, animated: true)
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
if isPortraid {
return UIScreen.main.bounds.height/3
} else {
return UIScreen.main.bounds.height/1.2
}
}
//更新搜索方法
func updateSearchResults(for searchController: UISearchController) {
if searchController.searchBar.text! == ""{
filteredData = data
} else {
filteredData = data.filter{($0 as AnyObject).contains(searchController.searchBar.text!)}
}
self.tableView.reloadData()
}
if searchController.searchBar.text! == ""
這幾乎可以肯定是罪犯。 UI對象的text
屬性為空時,通常為nil,因此,當您強制展開它時,應用程序崩潰。 除非絕對確定在那時您永遠不會將其包裝成零,否則切勿強行打開包裝。
您可以通過幾種不同的方式來處理此問題,這基本上等於在執行任何操作之前確保text
不為零。
就我個人而言,我將重寫if語句以解開非空情況下的可選內容:
if let text = searchController.searchBar.text, text != "" {
filteredData = data.filter{($0 as AnyObject).contains(text)}
} else {
filteredData = data
}
您還可以使用nil-coalescing :
if (searchController.searchBar.text ?? "") == ""
但就我個人而言,我更喜歡編寫它來避免強制展開,即使您確定它不是nil,所以我推薦第一個。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.