Swift - Search in UITableView [duplicate] - swift

Question

This question already has answers here:
Searchbar filtering issue
(3 answers)
Closed 3 years ago.
I'm trying to be able to search my Firebase data using a UISearchBar in my app & I am stuck. I am successfully receiving data from Firebase in a table view. I have a memories-writing app that the user can create memories (that are shown in a tableview from the firebase). memories has a title, description, a pic and a date and I want it to be able to search memories by the title.
I have a code here that doesn't work for some reason... il'l be glad if you could help me find out what's wrong in the code or find a replacement for this code :)
MemoryTitles class:
class MemoryTitles {
var title : String
init(withTitle: String) {
self.title = withTitle
}
}
MemoryViewController:
class MemoryViewController: UIViewController,UITableViewDelegate,UITableViewDataSource
// the filtered memories array for the search bar
var memoriesTitlesArr: [String] = []
var filteredDataa: [String] = []
// connections from storyboard to the code
#IBOutlet weak var tbl: UITableView!
#IBOutlet weak var searchBar: UISearchBar!
// an array of memories
var memories : [Memory] = []
var ref = Database.database().reference()
let sref = Storage.storage().reference()
var lastIndex : Int = 0
var strMode : String = ""
// TableView functions
// Return the number of rows in section
// section - an index number identifying a section in tableView.
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if searching {
return filteredDataa.count
} else {
return memories.count
}
// return memories.count
}
// Return Cell for row function : an object inheriting from UITableViewCell
// indexPath - an index path locating a row in tableView.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "iden")
if searching {
cell?.textLabel?.text = filteredDataa[indexPath.row]
} else {
var cell : UITableViewCell? = tableView.dequeueReusableCell(withIdentifier: "iden", for: indexPath)
if cell == nil
{
cell = UITableViewCell(style: UITableViewCell.CellStyle.default, reuseIdentifier: "iden")
}
let temp = memories[indexPath.row]
cell?.textLabel?.text = temp.title
cell?.imageView?.image = temp.image
return cell!
}
return cell!
}
// Can edit row : asks the data source to verify that the given row is editable.
// indexPath - an index path locating a row in tableView.
func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true // true if the row indicated by indexPath is editable; otherwise, false.
}
// Asks the data source to commit the insertion or deletion of a specified row.
// indexPath - an index path locating a row in tableView.
func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete // editingStyle - the cell editing style corresponding to a insertion or deletion requested for the row specified by indexPath.
{
let temp = self.memories[indexPath.row]
self.memories.remove(at: indexPath.row)
self.ref.child("MEmories/\(temp.key)").removeValue()
tableView.deleteRows(at: [indexPath as IndexPath], with: .fade)
}
}
override func viewDidLoad() {
super.viewDidLoad()
ref = Database.database().reference()
let rightButton = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(MemoryViewController.barButtonItemClicked(_:)))
self.navigationItem.setRightBarButton(rightButton, animated: true)
// Do any additional setup after loading the view.
self.loadMemories()
self.tbl.delegate = self
self.tbl.dataSource = self
}
// click on bar-Button function
#objc func barButtonItemClicked(_ sender:UIBarButtonItem)
{
print("+ clicked") // writes "+ clicked"
let addMemoryViewController = self.storyboard?.instantiateViewController(withIdentifier: "AddMemoryViewController") as! AddMemoryViewController
self.strMode = "newMemory"
self.navigationController?.pushViewController(addMemoryViewController, animated: true)
}
// Reading from NSUserDefault (A class that provides simple storage of different data types solution.)
func readFromNSUserDefault()-> Memory?
{
let d : UserDefaults = UserDefaults.standard
let strTitle = d.object(forKey: "title") as? String
let strBody = d.object(forKey: "body") as? String
let strImageRef = d.object(forKey: "imageRef") as? String
let uid = d.object(forKey: "uid") as? String
let imageData = d.object(forKey: "imageData") as? Data
let key = d.object(forKey: "key") as? String
let date = d.object(forKey: "date") as? NSNumber
let m = Memory(title: strTitle!, body: strBody!, key: key!, uid: uid!, imageRef: strImageRef!, date: date!) // A variable from type memory
m.image = UIImage(data: imageData!)
m.key = key!
return m
}
override func viewDidAppear(_ animated: Bool) {
let d = UserDefaults.standard
let newMemory = readFromNSUserDefault()
let userAdded = d.bool(forKey: "userAdded") //key new user = true
let userEdited = d.bool(forKey: "userEdited")//key user edited = true
if self.strMode == "newMemory" && userAdded
{
self.memories.append(newMemory!)
self.tbl.reloadData()
}
else if self.strMode == "edit" && userEdited
{
memories[lastIndex] = newMemory!
self.tbl.reloadData()
}
d.set(false, forKey: "userAdded")
d.set(false, forKey: "userEdited")
d.synchronize()
self.strMode = " "
}
// loading the memories from the Database
func loadMemories()
{
let UID = Auth.auth().currentUser!.uid
self.ref.child("MEmories").queryOrdered(byChild: "uid").queryEqual(toValue: UID).observeSingleEvent(of: .value, with: {
snapShot in
if let dict = snapShot.value as? NSDictionary
{
for d in (dict as? Dictionary<String,AnyObject>)!
{
let title = d.value["title"] as?String
let body = d.value["body"] as? String
let uid = d.value["uid"] as? String
let imageRef = d.value["imageRef"] as? String
let date = d.value["date"] as? NSNumber
let m = Memory(title: title!, body: body!, uid: uid!,imageRef:imageRef!, date: date!)
m.key = d.key
let tempImageRef = self.sref.child(m.imageRef)
tempImageRef.getData(maxSize: 500*1024*1024, completion: {(data,error) in
if error == nil
{
if let imageData = data
{
m.image = UIImage(data: imageData)
self.memories.append(m)
self.tbl.reloadData()
}
}
})
self.memoriesTitlesArr.append(title!)
}
}//end of if
})
}
// Notifies the view controller that a segue is about to be performed.
// segue - The segue object containing information about the view controllers involved in the segue.
// senderThe object that initiated the segue.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let identifier = segue.identifier
{
if identifier == "goToEdit"
{
let indexPath = self.tbl.indexPathForSelectedRow
let addMemoryViewController = segue.destination as! AddMemoryViewController
self.strMode = "edit"
self.lastIndex = (indexPath?.row)!
addMemoryViewController.mode = self.strMode
addMemoryViewController.current = memories[(indexPath?.row)!]
}
}
}
var searching = false
}
extension MemoryViewController: UISearchBarDelegate {
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
filteredDataa = memoriesTitlesArr.filter({ $0.prefix(searchText.count)==searchText.lowercased()})
searching = true
tbl.reloadData()
}
func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
searching = false
searchBar.text = ""
tbl.reloadData()
}
}

Answer 1

Here is how you can get that working.
1. First of all, there is no need for searching to maintain the state of searching and not searching.
2. Secondly, use filteredData as the dataSource for tableView instead of memories. filteredData will initially contain all the objects from memories, i.e.
var memories : [Memory] = []
lazy var filteredData = self.memories
The UITableViewDataSource methods will be like,
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.filteredData.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if let cell = tableView.dequeueReusableCell(withIdentifier: "iden") {
cell.textLabel?.text = self.filteredData[indexPath.row].title
return cell
}
return UITableViewCell()
}
Now, while searching update the filteredData with filtered memories using the relevant condition, i.e.
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
self.filteredData = self.memories.filter({ $0.title.hasPrefix(searchText) })
//change the condition as per your requirement......
self.tbl.reloadData()
}
func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
searchBar.text = nil
self.filteredData = self.memories
self.tbl.reloadData()
}
When cancelled, refill the filteredData with the whole memories data.