Using Swift 3
Error causing crash when I click button followButtonClick in MainController.swift. blogID is resulting in nil but when I print mainArray all the objects are there, so there is something wrong in my code that I can't fix. blogID is not being accessed right.
fatal error: unexpectedly found nil while unwrapping an Optional value
Instead of using NSCoder and UserDefaults to save the entire array of mainArray and followedArray, I'm saving the followed blogsID and then displaying those that we're saved by grabbing the objects that had their IDs saved.
MainController.swift
var mainArray = [Blog]()
var followedArray = [Blog]()
var filteredArray = [Blog]()
var followedIdentifiers = Set<String>()
// viewDidLoad
override func viewDidLoad() {
super.viewDidLoad()
retrieveDataFromServer()
loadUserDefaults()
}
// Title for Header
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
if !(searchController.isActive && searchController.searchBar.text != "") {
if section == 0 {
return "Followed Blogs"
}
else {
return "All Blogs"
}
}
return "Filtered Blogs"
}
// Number of Rows in Section
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if !(searchController.isActive && searchController.searchBar.text != "") {
if section == 0 {
return followedArray.count
}
else if (section == 1) {
return mainArray.count
}
}
return filteredArray.count
}
// CellForRowAt indexPath
public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let CellIdentifier = "Cell"
var cell = tableView.dequeueReusableCell(withIdentifier: CellIdentifier) as! CustomCell
if cell != cell {
cell = CustomCell(style: UITableViewCellStyle.default, reuseIdentifier: CellIdentifier)
}
// Configuring the cell
var blogObject: Blog
if !(searchController.isActive && searchController.searchBar.text != "") {
if indexPath.section == 0 {
blogObject = followedArray[indexPath.row]
cell.populateCell(blogObject, isFollowed: true, indexPath: indexPath, parentView: self)
}
else if indexPath.section == 1 {
blogObject = mainArray[indexPath.row]
cell.populateCell(blogObject, isFollowed: false, indexPath: indexPath, parentView: self)
}
}
else {
blogObject = filteredArray[indexPath.row]
cell.populateCell(blogObject, isFollowed: false, indexPath: indexPath, parentView: self)
}
return cell
}
// Follow Button
@IBAction func followButtonClick(_ sender: UIButton!) {
// Adding row to tag
let buttonPosition = (sender as AnyObject).convert(CGPoint.zero, to: self.myTableView)
if let indexPath = self.myTableView.indexPathForRow(at: buttonPosition) {
// Showing Status Labels
let cell = self.myTableView.cellForRow(at: indexPath) as! CustomCell
cell.firstStatusLabel.isHidden = false
cell.secondStatusLabel.isHidden = false
// Change Follow to Following
(sender as UIButton).setImage(UIImage(named: "follow.png")!, for: .normal)
cell.followButton.isHidden = true
cell.followedButton.isHidden = false
// Checking wether to import from mainArray or filteredArray to followedArray
if !(searchController.isActive && searchController.searchBar.text != "") {
self.myTableView.beginUpdates()
// -*- Error breaks here -*-
// Save identifier into followedIdentifier array
self.followedIdentifiers.insert(mainArray[indexPath.row].blogID)
// ----- Inserting Cell to followedArray -----
followedArray.insert(mainArray[indexPath.row], at: 0)
myTableView.insertRows(at: [IndexPath(row: 0, section: 0)], with: .fade)
// ----- Removing Cell from mainArray -----
mainArray.remove(at: indexPath.row)
let rowToRemove = indexPath.row
self.myTableView.deleteRows(at: [IndexPath(row: rowToRemove, section: 1)], with: .fade)
self.myTableView.endUpdates()
myTableView.reloadData()
// After Updating Table, Save the Archived to UserDefaults
saveUserDefaults()
}
else {
self.myTableView.beginUpdates()
// Remove identifier into followedIdentifier array
self.followedIdentifiers.remove(followedArray[indexPath.row].blogID)
// ----- Inserting Cell to followedArray -----
let blogObject: Blog = filteredArray[indexPath.row]
let indexOfObjectInArray = mainArray.index(of: blogObject)
followedArray.insert(blogObject, at: 0)
// ----- Removing Cell from filteredArray -----
filteredArray.remove(at: indexPath.row)
mainArray.remove(at: indexOfObjectInArray!)
let rowToRemove = indexPath.row
self.myTableView.deleteRows(at: [IndexPath(row: rowToRemove, section: 0)], with: .fade)
self.myTableView.endUpdates()
myTableView.reloadData()
// After Updating Table, Save the Archived to UserDefaults
saveUserDefaults()
}
}
}
// Unfollow Button
@IBAction func followedButtonClick(_ sender: UIButton!) {
// Adding row to tag
let buttonPosition = (sender as AnyObject).convert(CGPoint.zero, to: self.myTableView)
if let indexPath = self.myTableView.indexPathForRow(at: buttonPosition) {
// Hiding Status Labels
let cell = self.myTableView.cellForRow(at: indexPath) as! CustomCell
cell.firstStatusLabel.isHidden = true
cell.secondStatusLabel.isHidden = true
// Change Following to Follow
(sender as UIButton).setImage(UIImage(named: "followed.png")!, for: .normal)
cell.followButton.isHidden = false
cell.followedButton.isHidden = true
self.myTableView.beginUpdates()
// Remove identifier into followedIdentifier array
self.followedIdentifiers.remove(followedArray[indexPath.row].blogID)
// ----- Inserting Cell to mainArray -----
mainArray.insert(followedArray[indexPath.row], at: 0)
myTableView.insertRows(at: [IndexPath(row: 0, section: 1)], with: .fade)
// ----- Removing Cell from followedArray -----
followedArray.remove(at: indexPath.row)
let rowToRemove = indexPath.row
self.myTableView.deleteRows(at: [IndexPath(row: rowToRemove, section: 0)], with: .fade)
self.myTableView.endUpdates()
myTableView.reloadData()
// After Updating Table, Save the Archived to UserDefaults
saveUserDefaults()
}
}
// Saving UserDefaults
func saveUserDefaults() {
let key = "followedID"
UserDefaults.standard.setValue(self.followedIdentifiers, forKey: key)
UserDefaults.standard.synchronize()
}
// Load UserDefaults
func loadUserDefaults() {
let key = "followedID"
UserDefaults.standard.setValue(Array(self.followedIdentifiers), forKey: key)
self.followedIdentifiers = Set(UserDefaults.standard.stringArray(forKey: key)!)
}
// Retrieving Data from Server
func retrieveDataFromServer() {
let getDataURL = "http://example.com/receiving.php"
let url: NSURL = NSURL(string: getDataURL)!
do {
let data: Data = try Data(contentsOf: url as URL)
let jsonArray = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as! NSMutableArray
// Clear the arrays
self.followedArray = [Blog]()
self.mainArray = [Blog()]
// Looping through jsonArray
for jsonObject in jsonArray {
if let blog = Blog.createBlog(from: jsonObject as AnyObject) {
// Check if identifiers match
if followedIdentifiers.contains(blog.blogID) {
self.followedArray.append(blog)
} else {
self.mainArray.append(blog)
}
}
}
} catch {
print("Error: (Retrieving Data)")
}
myTableView.reloadData()
}
Blog.swift - Handles the Blogs objects
import UIKit
class Blog: NSObject, NSCoding {
var blogName: String!
var blogStatus1: String!
var blogStatus2: String!
var blogURL: String!
var blogID: String!
var blogType: String!
var blogDate: String!
var blogPop: String!
static func createBlog(from jsonObject: AnyObject) -> Blog? {
guard let bID: String = jsonObject.object(forKey: "id") as? String,
let bName: String = jsonObject.object(forKey: "blogName") as? String,
let bStatus1: String = jsonObject.object(forKey: "blogStatus1") as? String,
let bStatus2: String = jsonObject.object(forKey: "blogStatus2") as? String,
let bURL: String = jsonObject.object(forKey: "blogURL") as? String,
let bType: String = jsonObject.object(forKey: "blogType") as? String,
let bDate: String = jsonObject.object(forKey: "blogDate") as? String,
let bPop: String = jsonObject.object(forKey: "blogPop") as? String
else {
print("Error: (Creating Blog Object)")
return nil
}
let blog = Blog()
blog.blogName = bName
blog.blogStatus1 = bStatus1
blog.blogStatus2 = bStatus2
blog.blogURL = bURL
blog.blogID = bID
blog.blogType = bType
blog.blogDate = bDate
blog.blogPop = bPop
return blog
}
convenience required init?(coder aDecoder: NSCoder) {
self.init ()
self.blogName = aDecoder.decodeObject(forKey: "blogName") as! String
self.blogStatus1 = aDecoder.decodeObject(forKey: "blogStatus1") as! String
self.blogStatus2 = aDecoder.decodeObject(forKey: "blogStatus2") as! String
self.blogURL = aDecoder.decodeObject(forKey: "blogURL") as! String
self.blogID = aDecoder.decodeObject(forKey: "blogID") as! String
self.blogType = aDecoder.decodeObject(forKey: "blogType") as! String
self.blogDate = aDecoder.decodeObject(forKey: "blogDate") as! String
self.blogPop = aDecoder.decodeObject(forKey: "blogPop") as! String
}
func encode(with aCoder: NSCoder) {
aCoder.encode(blogName, forKey: "blogName")
aCoder.encode(blogStatus1, forKey: "blogStatus1")
aCoder.encode(blogStatus2, forKey: "blogStatus2")
aCoder.encode(blogURL, forKey: "blogURL")
aCoder.encode(blogID, forKey: "blogID")
aCoder.encode(blogType, forKey: "blogType")
aCoder.encode(blogDate, forKey: "blogDate")
aCoder.encode(blogPop, forKey: "blogPop")
}
}
