error: Index out of range in segment control - ios

Question

While using segment control to populate the respective list under different segments, issues I am facing are as below
When the segment control is loaded in the tableview , the first segment is working fine and when I switch second segment it do populate the list but it gives error of Index Out Of Range when the list scrolled
The second segment control should load the different list as per the filter, but it loads the same list as the first segment control
I am using Swift IOS and Firestore Database for this
Below is the code I am sharing
class FirstSegementViewController: UIViewController {
#IBOutlet var segmentControl:UISegmentedControl!
#IBOutlet var tableView: UITableView!
var firstDetails:[FirstDetails] = []
var secondDetails:[SecondDetails] = []
var postKey:String = ""
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
tableView.delegate = self
// Do any additional setup after loading the view.
retrieveAllPosts()
}
func retrieveAllPosts(){
let postsRef = Firestore.firestore().collection("posts").whereField("post_author_id", isEqualTo: Auth.auth().currentUser!.uid
).whereField("status", isEqualTo: false).limit(to: 50)
postsRef.getDocuments { (snapshot, error) in
if let error = error {
print(error.localizedDescription)
} else {
if let snapshot = snapshot {
for document in snapshot.documents {
let data = document.data()
//self.postKey = document.documentID
let username = data["post_author_username"] as? String ?? ""
let postTitle = data["postTitle"] as? String ?? ""
let postcategory = data["postcategory"] as? String ?? ""
let postContent = data["postContent"] as? String ?? ""
let postAuthorProfilePicUrl = data["post_user_profile_pic_url"] as? String ?? ""
let postAuthorSpinnerC = data["post_author_spinnerC"] as? String
let newSourse = FirstDetails(_documentId: document.documentID, _username: username, _postTitle: postTitle, _postcategory: postcategory, _postContent: postContent, _postuserprofileImagUrl: postAuthorProfilePicUrl, _postAuthorSpinncerC: postAuthorSpinnerC)
self.firstDetails.append(newSourse)
// print(self.postKey)
}
self.tableView.reloadData()
}
}
}
}
func retrieveAllPosts2(){
let postsRef = Firestore.firestore().collection("posts").whereField("post_author_id", isEqualTo: Auth.auth().currentUser!.uid).whereField("status", isEqualTo: true).limit(to: 50)
postsRef.getDocuments { (snapshot, error) in
if let error = error {
print(error.localizedDescription)
} else {
if let snapshot = snapshot {
for document in snapshot.documents {
let data = document.data()
//self.postKey = document.documentID
let username = data["post_author_username"] as? String ?? ""
let postTitle = data["postTitle"] as? String ?? ""
let postcategory = data["postcategory"] as? String ?? ""
let postContent = data["postContent"] as? String ?? ""
let postAuthorProfilePicUrl = data["post_user_profile_pic_url"] as? String ?? ""
let postAuthorSpinnerC = data["post_author_spinnerC"] as? String
let newSourse1 = SecondDetails(_documentId: document.documentID, _username: username, _postTitle: postTitle, _postcategory: postcategory, _postContent: postContent, _postuserprofileImagUrl: postAuthorProfilePicUrl, _postAuthorSpinncerC: postAuthorSpinnerC)
self.secondDetails.append(newSourse1)
}
self.tableView.reloadData()
}
}
}
}
#IBAction func indexChanged(_ sender: UISegmentedControl) {
switch segmentControl.selectedSegmentIndex
{
case 0:
retrieveAllPosts()
// label1.text = "First Segment Selected"
case 1:
retrieveAllPosts2()
// label1.text = "Second Segment Selected"
default:
break
}
//self.tableView.reloadData()
}
#objc func toComments(_ sender: AnyObject) {
let commentbutton = sender as! UIButton
let post = firstDetails[commentbutton.tag]
postKey = post._documentId // or what key value it is
print("hello")
performSegue(withIdentifier: "toCommentsListforMWs", sender: self)
}
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destination.
// Pass the selected object to the new view controller.
var vc = segue.destination as! CommentListViewController
vc.postId = postKey
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destination.
// Pass the selected object to the new view controller.
}
*/
}
extension FirstSegementViewController: UITableViewDelegate, UITableViewDataSource{
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
var value = 0
switch segmentControl.selectedSegmentIndex{
case 0:
value = firstDetails.count
break
case 1:
value = secondDetails.count
break
default:
break
}
return value
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "MyCell", for: indexPath) as! MyWsPostCell
switch segmentControl.selectedSegmentIndex{
case 0:
cell.firstdetails1 = firstDetails[indexPath.row]
cell.commentbutton.tag = indexPath.row
cell.commentbutton.addTarget(self, action: #selector(toComments(_:)), for: .touchUpInside)
break
case 1:
cell.completed1 = secondDetails[indexPath.row]
cell.commentbutton.tag = indexPath.row
cell.commentbutton.addTarget(self, action: #selector(toComments(_:)), for: .touchUpInside)
break
default:
break
}
return cell
}
}

Answer 1

Change your indexChanged(_ sender: UISegmentedControl) function like this:
#IBAction func indexChanged(_ sender: UISegmentedControl) {
switch segmentControl.selectedSegmentIndex
{
case 0:
self.firstDetails.removeAll()
retrieveAllPosts()
// label1.text = "First Segment Selected"
case 1:
self.secondDetails.removeAll()
retrieveAllPosts2()
// label1.text = "Second Segment Selected"
default:
break
}
//self.tableView.reloadData()
}

Answer 2

In your retrieveAllPosts() and retrieveAllPosts2() you need to empty the data you have already stored in the firstDetails and secondDetails array. Currently you are just appending the data everytime user changes the segment index.
func retrieveAllPosts() {
self.firstDetails = []
//all of your code here
}
func retrieveAllPosts2() {
self.secondDetails = []
//all of your code here
}

Answer 3

Before your Api hit, or before adding data to array remove the previous data in the array.
#IBAction func indexChanged(_ sender: UISegmentedControl) {
switch segmentControl.selectedSegmentIndex
{
case 0:
self.firstDetails.removeAll()// Remove data in array before u call Api
retrieveAllPosts()
case 1:
self.secondDetails.removeAll()// Remove data in array before u call Api
retrieveAllPosts2()
default:
break
}
}