Ios 如何筛选核心数据中包含对象的tableview?
我正在创建一个联系人应用程序,到目前为止,我已成功地将项目保存到我的tableview。我有一个搜索栏,我想按名字过滤我的单元格,我知道因为我在处理核心数据,所以我必须使用fetchResultsController和NSPredicate。我很难弄清楚这一切,也许有人能帮我解决 这里还有我的核心数据实体,以防万一 实体:联系人 属性:Ios 如何筛选核心数据中包含对象的tableview?,ios,swift,uitableview,core-data,nsfetchedresultscontroller,Ios,Swift,Uitableview,Core Data,Nsfetchedresultscontroller,我正在创建一个联系人应用程序,到目前为止,我已成功地将项目保存到我的tableview。我有一个搜索栏,我想按名字过滤我的单元格,我知道因为我在处理核心数据,所以我必须使用fetchResultsController和NSPredicate。我很难弄清楚这一切,也许有人能帮我解决 这里还有我的核心数据实体,以防万一 实体:联系人 属性: 名字,字符串 姓氏,字符串 出生日期,字符串 电话号码,字符串 zipCode,字符串 我知道有些代码可能不完整,但我只需要知道该怎么做。我只想让用户键入一
- 名字,字符串
- 姓氏,字符串
- 出生日期,字符串
- 电话号码,字符串
- zipCode,字符串
import UIKit
import CoreData
class ContactsTableVC: UITableViewController, UISearchBarDelegate, NSFetchedResultsControllerDelegate {
@IBOutlet weak var searchBar: UISearchBar!
var isFiltered: Bool = false
//Holds the core data model
var persons: [Person] = []
override func viewDidLoad() {
super.viewDidLoad()
searchBar.delegate = self
self.tableView.separatorStyle = UITableViewCellSeparatorStyle.none
self.tableView.backgroundColor = UIColor(red: 240/255.0, green: 240/255.0, blue: 240/255.0, alpha: 1.0)
fetch()
self.tableView.reloadData()
}
func getContext () -> NSManagedObjectContext {
let appDelegate = UIApplication.shared.delegate as! AppDelegate
return appDelegate.persistentContainer.viewContext
}
// MARK: - Searchbar
//add fetchrequest to did ebgin editing
func searchBarTextDidBeginEditing(_ searchBar: UISearchBar) {
}
func searchBarTextDidEndEditing(_ searchBar: UISearchBar) {
if(searchBar.text == "") {
isFiltered = false
} else {
isFiltered = true
}
}
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
filter(text: searchText)
}
// MARK: - Fetchresults controller / filtering data
func filter(text: String) {
//Create fetch request
let fetchRequest = NSFetchRequest<Person>()
// guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else { return } replaced with getcontext
// let managedObjectContext = appDelegate.persistentContainer.viewContext
let entity = NSEntityDescription.entity(forEntityName: "Contact", in: getContext())
fetchRequest.entity = entity
let sortDescriptor = NSSortDescriptor(key: "firstName", ascending: false)
let sortDescriptors: [Any] = [sortDescriptor]
fetchRequest.sortDescriptors = sortDescriptors as? [NSSortDescriptor] ?? [NSSortDescriptor]()
if(text.characters.count > 0) {
let predicate = NSPredicate(format: "(firstName CONTAINS[c] %@)", text)
fetchRequest.predicate = predicate
}
let loadedEntities: [Person]? = try? getContext().fetch(fetchRequest)
filteredContacts = [Any](arrayLiteral: loadedEntities) as! [Person]
self.tableView.reloadData()
}
// MARK: - Data Source
func fetch() {
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else { return }
let managedObjectContext = appDelegate.persistentContainer.viewContext
let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName:"Contact")
do {
persons = try managedObjectContext.fetch(fetchRequest) as! [Person] //NSManagedObject
} catch let error as NSError {
print("Could not fetch. \(error)")
}
}
func save(firstName: String, lastName: String, dob: String, phoneNumber: String, zipCode: String) {
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else { return }
let managedObjectContext = appDelegate.persistentContainer.viewContext
guard let entity = NSEntityDescription.entity(forEntityName:"Contact", in: managedObjectContext) else { return }
let person = NSManagedObject(entity: entity, insertInto: managedObjectContext)
person.setValue(firstName, forKey: "firstName")
person.setValue(lastName, forKey: "lastName")
person.setValue(dob, forKey: "dateOfBirth")
person.setValue(phoneNumber, forKey: "phoneNumber")
person.setValue(zipCode, forKey: "zipCode")
do {
try managedObjectContext.save()
self.persons.append(person as! Person) //previously just contact, no casting!
} catch let error as NSError {
print("Couldn't save. \(error)")
}
}
func update(indexPath: IndexPath, firstName: String, lastName: String, dob: String, phoneNumber: String, zipCode: String) {
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else { return }
let managedObjectContext = appDelegate.persistentContainer.viewContext
let contact = persons[indexPath.row]
contact.setValue(firstName, forKey: "firstName")
contact.setValue(lastName, forKey: "lastName")
contact.setValue(dob, forKey: "dateOfBirth")
contact.setValue(phoneNumber, forKey: "phoneNumber")
contact.setValue(zipCode, forKey: "zipCode")
do {
try managedObjectContext.save()
persons[indexPath.row] = contact
} catch let error as NSError {
print("Couldn't update. \(error)")
}
}
func delete(_ contact: NSManagedObject, at indexPath: IndexPath) {
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else { return }
let managedObjectContext = appDelegate.persistentContainer.viewContext
managedObjectContext.delete(contact)
persons.remove(at: indexPath.row)
//Always remember to save after deleting, updates Core Data
do {
try managedObjectContext.save()
} catch {
print("Something went wrong \(error.localizedDescription)")
}
}
// MARK: - Table View Setup
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return persons.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "ContactCell", for: indexPath) as? PersonsCell
let person = persons[indexPath.row]
cell?.firstName?.text = person.value(forKey:"firstName") as? String
cell?.lastName?.text = person.value(forKey:"lastName") as? String
cell?.dob?.text = person.value(forKey:"dateOfBirth") as? String
cell?.phoneNumber?.text = person.value(forKey:"phoneNumber") as? String
cell?.zipCode?.text = person.value(forKey:"zipCode") as? String
return cell!
}
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 75
}
// Override to support conditional editing of the table view.
override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
// MARK: - Navigation
@IBAction func unwindToContactsList(segue:UIStoryboardSegue) {
if let viewController = segue.source as? AddContactVC {
guard let _firstName: String = viewController.firstNameLbl.text,
let _lastName: String = viewController.lastNameLbl.text,
let _dob: String = viewController.dateOfBirthLbl.text,
let _phoneNumber: String = viewController.phoneNumberLbl.text,
let _zipCode: String = viewController.zipCodeLbl.text
else { return }
if _firstName != "" && _lastName != "" && _dob != "" && _phoneNumber != "" && _zipCode != "" {
if let indexPath = viewController.indexPathForContact {
update(indexPath: indexPath, firstName: _firstName, lastName: _lastName, dob: _dob, phoneNumber: _phoneNumber, zipCode: _zipCode)
print("Any updates?")
} else {
save(firstName: _firstName, lastName: _lastName, dob: _dob, phoneNumber: _phoneNumber, zipCode: _zipCode)
print("added to tableview") //this runs twice for some reason...
}
}
tableView.reloadData()
} else if let viewController = segue.source as? EditContactVC {
if viewController.isDeleted {
guard let indexPath: IndexPath = viewController.indexPath else { return }
let person = persons[indexPath.row]
delete(person, at: indexPath)
tableView.reloadData()
}
}
}
}
导入UIKit
导入CoreData
类ContactStableC:UITableViewController、UISearchBarDelegate、NSFetchedResultsControllerDelegate{
@ibvar搜索栏:UISearchBar!
变量isFiltered:Bool=false
//保存核心数据模型
变量人员:[人员]=[]
重写func viewDidLoad(){
super.viewDidLoad()
searchBar.delegate=self
self.tableView.separatorStyle=UITableViewCellSeparatorStyle.none
self.tableView.backgroundColor=UIColor(红色:240/255.0,绿色:240/255.0,蓝色:240/255.0,alpha:1.0)
fetch()
self.tableView.reloadData()
}
func getContext()->NSManagedObjectContext{
让appDelegate=UIApplication.shared.delegate为!appDelegate
返回appDelegate.persistentContainer.viewContext
}
//标记:-搜索栏
//将fetchrequest添加到did ebgin编辑
func searchBarTextDidBeginEditing(searchBar:UISearchBar){
}
func SearchBartextdidediting(searchBar:UISearchBar){
如果(searchBar.text==“”){
isFiltered=false
}否则{
isFiltered=true
}
}
func searchBar(searchBar:UISearchBar,textDidChange searchText:String){
过滤器(文本:searchText)
}
//标记:-获取结果控制器/筛选数据
func筛选器(文本:字符串){
//创建提取请求
让fetchRequest=NSFetchRequest()
//让appDelegate=UIApplication.shared.delegate作为?appDelegate else{return}替换为getcontext
//让managedObjectContext=appDelegate.persistentContainer.viewContext
让entity=NSEntityDescription.entity(在:getContext()中,名为“Contact”)
fetchRequest.entity=实体
让sortDescriptor=NSSortDescriptor(键:“firstName”,升序:false)
让sortDescriptor:[任何]=[sortDescriptor]
fetchRequest.sortDescriptors=sortDescriptors为?[NSSortDescriptor]??[NSSortDescriptor]()
如果(text.characters.count>0){
let predicate=NSPredicate(格式:“(firstName包含[c]]@)”,文本)
fetchRequest.predicate=谓词
}
让loadedEntities:[Person]?=尝试?getContext().fetch(fetchRequest)
filteredContacts=[Any](ArrayTerral:loadedEntities)作为![Person]
self.tableView.reloadData()
}
//标记:-数据源
func fetch(){
让appDelegate=UIApplication.shared.delegate作为?appDelegate else{return}
让managedObjectContext=appDelegate.persistentContainer.viewContext
let fetchRequest=NSFetchRequest(entityName:“联系人”)
做{
persons=尝试managedObjectContext.fetch(fetchRequest)作为![Person]//NSManagedObject
}将let错误捕获为NSError{
打印(“无法获取.\(错误)”)
}
}
func save(firstName:String,lastName:String,dob:String,phoneNumber:String,zipCode:String){
让appDelegate=UIApplication.shared.delegate作为?appDelegate else{return}
让managedObjectContext=appDelegate.persistentContainer.viewContext
guard let entity=NSEntityDescription.entity(forEntityName:“Contact”,在:managedObjectContext中)else{return}
让person=NSManagedObject(实体:实体,插入到:ManagedObject上下文)
person.setValue(firstName,forKey:“firstName”)
person.setValue(lastName,forKey:“lastName”)
person.setValue(dob,forKey:“出生日期”)
person.setValue(phoneNumber,forKey:“phoneNumber”)
person.setValue(zipCode,forKey:“zipCode”)
做{
请尝试managedObjectContext.save()
self.persons.append(person as!person)//以前只需联系,无需施法!
}将let错误捕获为NSError{
打印(“无法保存。\(错误)”)
}
}
func更新(indepath:indepath,firstName:String,lastName:String,dob:String,phoneNumber:String,zipCode:String){
让appDelegate=UIApplication.shared.delegate作为?appDelegate else{return}
让managedObjectContext=appDelegate.persistentContainer.viewContext
let contact=persons[indexPath.row]
contact.setValue(firstName,forKey:“firstName”)
contact.setValue(lastName,forKey:“lastName”)
contact.setValue(dob,forKey:“出生日期”)
contact.setValue(phoneNumber,forKey:“phoneNumber”)
contact.setValue(zipCode,forKey:“zipCode”)
做{
请尝试managedObjectContext.save()
人员[indexath.row]=联系人
}将let错误捕获为NSError{
打印(“无法更新。\(错误)”)
}
}
func delete(contact:NSManagedObject,位于indexath:indexPath){
让appDelegate=UIApplication.shared.delegate作为?appDelegate else{return}
让managedObjectContext=appDelegate.persistentContainer.viewContext
managedObjectContext.delete(联系人)
persons.remove(位于:indexPath.row)
//阿尔瓦
class ContactViewController: UITableViewController {
let fetchedResultsController: NSFetchedResultsController<Contact>!
func searchTextFieldDidEditingChanged(_ textField: UITextField) {
let text = textField.text ?? ""
refetch(with: text)
}
// The key is you need change the predicate when searchTextField's
// value changed, and invoke proformFetch() again
func refetch(with text: String) {
let predicate = NSPredicate(format: "firstName CONTAINS %@", text)
fetchedResultsController.fetchRequest.predicate = predicate
do {
try self.fetchedResultsController.performFetch()
tableView.reloadData()
} catch let error as NSError {
loggingPrint("Error: \(error.localizedDescription)")
}
}
}
// MARK: - Table datasource
extension ContactViewController {
override func numberOfSections(in tableView: UITableView) -> Int {
return fetchedResultsController.sections!.count
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
let sectionInfo = fetchedResultsController.sections![section]
return sectionInfo.numberOfObjects
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "ContactCell", for: indexPath) as? PersonsCell
let contact = fetchedResultsController.object(at: indexPath)
cell.contact = contact
return cell!
}
}