Index out of range when i use to celll( Swift) - ios

people, I have this issue when I try back image from different cell
(Thread 1: Fatal error: Index out of range)
what I'm doing here ?
I'm trying to build an Instagram clone and in my home view controller that what should posts show up. I make navigation with a table view and that table view has 2 cell with the different identifier. cell number 1 it's a header that brings data from users table to my username label and profile image. and cell number 2 its for posts its should bring post data like image and caption. I use firebase database.
my code :
import UIKit
import FirebaseAuth
import FirebaseDatabase
class HomeViewController: UIViewController ,UITableViewDelegate {
#IBOutlet weak var tableview: UITableView!
var posts = [Post]()
var users = [UserD]()
override func viewDidLoad() {
super.viewDidLoad()
tableview.dataSource = self
loadposts()
userDetal()
// var post = Post(captiontxt: "test", photoUrlString: "urll")
// print(post.caption)
// print(post.photoUrl)
}
func loadposts() {
Database.database().reference().child("posts").observe(.childAdded){ (snapshot: DataSnapshot)in
print(Thread.isMainThread)
if let dict = snapshot.value as? [String: Any]{
let captiontxt = dict["caption"] as! String
let photoUrlString = dict["photoUrl"] as! String
let post = Post(captiontxt: captiontxt, photoUrlString: photoUrlString)
self.posts.append(post)
print(self.posts)
self.tableview.reloadData()
}
}
}
func userDetal() {
Database.database().reference().child("users").observe(.childAdded){ (snapshot: DataSnapshot)in
print(Thread.isMainThread)
if let dict = snapshot.value as? [String: Any]{
let usernametxt = dict["username"] as! String
let profileImageUrlString = dict["profileImageUrl"] as! String
let user = UserD(usernametxt: usernametxt, profileImageUrlString: profileImageUrlString)
self.users.append(user)
print(self.users)
self.tableview.reloadData()
}
}
}
#IBAction func logout(_ sender: Any) {
do {
try Auth.auth().signOut()
}catch let logoutErrorr{
print(logoutErrorr)
}
let storyboard = UIStoryboard(name: "Start", bundle: nil)
let signinVC = storyboard.instantiateViewController(withIdentifier: "SigninViewController")
self.present(signinVC, animated: true, completion: nil)
}
}
extension HomeViewController: UITableViewDataSource{
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return posts.count
}
func numberOfSections(in tableView: UITableView) -> Int {
return users.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if indexPath.row == 0{
let cell = tableview.dequeueReusableCell(withIdentifier: "imagecell", for: indexPath) as! PostCellTableViewCell
cell.postimage.image = nil
cell.tag += 1
let tag = cell.tag
cell.captionLabel.text = posts[indexPath.row].caption
let photoUrl = posts[indexPath.row].photoUrl
getImage(url: photoUrl) { photo in
if photo != nil {
if cell.tag == tag {
DispatchQueue.main.async {
cell.postimage.image = photo
}
}
}
}
return cell
} else if indexPath.row == 1 {
let cell = tableview.dequeueReusableCell(withIdentifier: "postcell", for: indexPath) as! HeaderTableViewCell
cell.userimage.image = nil
cell.tag += 1
let tag = cell.tag
cell.usernamelabel.text = users[indexPath.row].username
//Error showing here????????????????????????????????????
let profileImageUrl = users[indexPath.row].profileImageUrl
getImage(url: profileImageUrl) { photo in
if photo != nil {
if cell.tag == tag {
DispatchQueue.main.async {
cell.userimage.image = photo
}
}
}
}
return cell
}
return UITableViewCell()
}
func getImage(url: String, completion: #escaping (UIImage?) -> ()) {
URLSession.shared.dataTask(with: URL(string: url)!) { data, response, error in
if error == nil {
completion(UIImage(data: data!))
} else {
completion(nil)
}
}.resume()
}
}

try this one.
cell.tag = indexpath.row

What is the content of users array ?
Are you sure you want to define as many sections as users or as many rows ?
In this case use
func numberOfRows(in tableView: NSTableView) -> Int {
return users.count
}
As explained, you need to rewrite completely cellForRowAt
It should look like this :
func tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int) -> NSView? {
if row < users.count {
let user = users[row]
if let cellView = tableView.makeView(withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "CellID"), owner: self) {
(cellView as! NSTableCellView).textField?.stringValue = user.name
// do the same for all the fields you need to set
return cellView
} else {
return nil
}
}
return nil
}

thanx, my friend, I found a good way to contain my cell. for post cell, i just use cellForRowAt and but the post data. for header cell i use viewForHeaderInSection
and but my user data with heightForHeaderInSection. to make the high for a view

Related

how to make checkmark to be selected depending on the array in swift 3?

I am having array in which selected name will be stored and passed to before view controller and when ever i need to go previous view controller then the previously selected check mark needs to be selected but here it is enabling the last selected element only the problem is if i select three then it is not selecting three it is check marking only the last element but i need the three selected can anyone help me how to make the check mark to be selected for three elements ?
protocol ArrayToPass: class {
func selectedArrayToPass(selectedStrings: [String])
}
class FilterSelectionViewController: UIViewController,UITableViewDataSource,UITableViewDelegate {
var productName = [String]()
var productprice = [String]()
var imageArray = [String]()
var idArray = [Int]()
let urlString = "http://www.json-generator.com/api/json/get/bOYOrkIOSq?indent=2"
var values = [String]()
var selected: Bool?
var delegate: ArrayToPass?
var nameSelection: Bool?
var namesArray = [String]()
override func viewDidLoad() {
super.viewDidLoad()
self.downloadJsonWithURL()
tableDetails.separatorInset = UIEdgeInsets.zero
activityIndicator.startAnimating()
tableDetails.isHidden = true
tableDetails.dataSource = self
tableDetails.delegate = self
let rightBarButton = UIBarButtonItem(title: "Apply", style: UIBarButtonItemStyle.plain, target: self, action: #selector(applyBarButtonActionTapped(_:)))
self.navigationItem.rightBarButtonItem = rightBarButton
tableDetails.estimatedRowHeight = UITableViewAutomaticDimension
tableDetails.rowHeight = 60
// Do any additional setup after loading the view.
}
func applyBarButtonActionTapped(_ sender:UIBarButtonItem!){
self.delegate?.selectedArrayToPass(selectedStrings: values)
navigationController?.popViewController(animated: true)
}
func downloadJsonWithURL() {
let url = NSURL(string: urlString)
URLSession.shared.dataTask(with: (url as URL?)!, completionHandler: {(data, response, error) -> Void in
if let jsonObj = try? JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? NSArray {
for item in jsonObj! {
if let itemDict = item as? NSDictionary{
if let name = itemDict.value(forKey: "name") {
self.productName.append(name as! String)
}
if let price = itemDict.value(forKey: "value") {
self.productprice.append(price as! String)
}
if let image = itemDict.value(forKey: "img") {
self.imageArray.append(image as! String)
}
if let id = itemDict.value(forKey: "id") {
self.idArray.append(id as! Int)
}
}
}
OperationQueue.main.addOperation({
self.tableDetails.reloadData()
})
}
}).resume()
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return productName.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "filterSelectionCell", for: indexPath) as! FilterSelectionCell
activityIndicator.stopAnimating()
activityIndicator.hidesWhenStopped = true
tableDetails.isHidden = false
cell.brandProductName.text = productName[indexPath.row]
if nameSelection == true{
if namesArray.count != 0 {
print(namesArray)
for name in namesArray{
if productName[indexPath.row].contains(name){
print(productName[indexPath.row])
cell.accessoryType = .checkmark
}
else {
cell.accessoryType = .none
}
}
}
}
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
selected = false
if let cell = tableView.cellForRow(at: indexPath as IndexPath) {
if cell.accessoryType == .checkmark{
cell.accessoryType = .none
print("\(productName[indexPath.row])")
values = values.filter{$0 != "\(productName[indexPath.row])"}
selected = true
}
else{
cell.accessoryType = .checkmark
}
}
if selected == true{
print(values)
}
else{
getAllTextFromTableView()
}
print(values)
}
func getAllTextFromTableView() {
guard let indexPaths = self.tableDetails.indexPathsForSelectedRows else { // if no selected cells just return
return
}
for indexPath in indexPaths {
values.append(productName[indexPath.row])
}
}
here is the image for this
Basically do not manipulate the view (the cell). Use a data model.
struct Product {
let name : String
let value : String
let img : String
let id : Int
var selected = false
init(dict : [String:Any]) {
self.name = dict["name"] as? String ?? ""
self.value = dict["value"] as? String ?? ""
self.img = dict["img"] as? String ?? ""
self.id = dict["id"] as? Int ?? 0
}
}
And never use multiple arrays as data source . That's a very bad habit.
Declare the data source array as
var products = [Product]()
Parse the JSON data and do a (better) error handling
func downloadJsonWithURL() {
let url = URL(string: urlString)!
let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
if error != nil { print(error!); return }
do {
if let jsonObj = try JSONSerialization.jsonObject(with: data!) as? [[String:Any]] {
self.products = jsonObj.map{ Product(dict: $0) }
DispatchQueue.main.async {
self.tableDetails.reloadData()
}
}
} catch {
print(error)
}
}
task.resume()
}
in cellForRow... assign the name to the label and set the checkmark depending on selected
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "filterSelectionCell", for: indexPath)
let product = products[indexPath.row]
cell.textLabel!.text = product.name
cell.accessoryType = product.selected ? .checkmark : .none
return cell
}
In didSelect... toggle selected and reload the row
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let selected = products[indexPath.row].selected
products[indexPath.row].selected = !selected
tableView.reloadRows(at: [indexPath], with: .none)
}
To get all selected items is very easy, too.
let selectedItems = products.filter{ $0.selected }
or get only the names
let selectedNames = products.filter{ $0.selected }.map{ $0.name }
There is no need at all to get any information from the view. The controller gets the information always from the model and uses tableview data source and delegate to update the view.
If you want to pass data to another view controller pass Product instances. They contain all relevant information.

Reloading TableView using UISegmentedControl in Swift [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 5 years ago.
Improve this question
I am creating a search screen where you can select among four different options. If one selects people, then people array gets loaded in table view cells , if he selects images then image posts get loaded in tableview .
how can i achieve the design posted above? i have created four different cells and nib files and based on the option selected in segment control , i have to load those nib files in table cell.
UPDATE ::::
I am updating all my code here which i have combined into one file.
import UIKit
import Alamofire
class SearchViewController: UIViewController , UITableViewDataSource , UITableViewDelegate , UISearchBarDelegate{
var imagepost : ImageSeachPostData!
var imageposts = [ImageSeachPostData]()
var videopost : VideoSeachPostData!
var videoposts = [VideoSeachPostData]()
var statuspost : StatusSearchPostData!
var statusposts = [StatusSearchPostData]()
var penpalpost : PenpalSearchPostData!
var penpalposts = [PenpalSearchPostData]()
var tablearray : NSArray = []
typealias DownloadComplete = () -> ()
#IBOutlet weak var searchTable: UITableView!
#IBOutlet weak var searchBar: UISearchBar!
#IBOutlet weak var searchTypeSegmentControl: UISegmentedControl!
override func viewDidLoad() {
super.viewDidLoad()
searchTable.dataSource = self
searchTable.delegate = self
searchBar.delegate = self
searchPassed()
}
#IBAction func onChangeSegment(_ sender: UISegmentedControl)
{
self.searchTable.reloadData()
}
func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {
view.endEditing(true)
}
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
if searchBar.text == nil || searchBar.text == "" {
searchTable.reloadData()
view.endEditing(true)
} else {
searchPassed()
searchTable.reloadData()
}
}
func searchPassed()
{
let searchText = "Postpositives"
print(searchText)
var request = URLRequest(url: URL(string: "https://www.example.com/search")!)
request.httpMethod = "GET"
let postString = "q=\(searchText)"
request.httpBody = postString.data(using: .utf8)
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else { // check for fundamental networking error
print("error=\(String(describing: error))")
print("cant run")
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(String(describing: response))")
print("\(searchText)")
}
else {
let responseString = String(data: data, encoding: .utf8)
print("responseString = \(String(describing: responseString))")
// func downloadPostData(completed: #escaping DownloadComplete) {
Alamofire.request("https://www.example.com/api/search?q=\(searchText)").responseJSON { response in
let result = response.result
if let dict = result.value as? Dictionary<String,AnyObject> {
if let successcode = dict["STATUS_CODE"] as? Int {
if successcode == 1 {
if let postsArray = dict["posts"] as? [Dictionary<String,AnyObject>]
{
for obj in postsArray
{
let mediatype = dict["media_type"] as! String?
if mediatype == "image"
{
let imagepost = ImageSeachPostData(postDict: obj)
self.imageposts.append(imagepost)
}
else if mediatype == "video"
{
let videopost = VideoSeachPostData(postDict: obj)
self.videoposts.append(videopost)
}
else if mediatype == "null"
{
let statuspost = StatusSearchPostData(postDict: obj)
self.statusposts.append(statuspost)
}
let penpalpost = PenpalSearchPostData(postDict: obj)
self.penpalposts.append(penpalpost)
}
self.searchTable.reloadData()
}
}
}
}
}
}
}
}
task.resume()
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
let selectedIndex = self.searchTypeSegmentControl.selectedSegmentIndex
switch selectedIndex
{
case 0:
return penpalposts.count
case 1:
return statusposts.count
case 2:
return imageposts.count
case 3:
return videoposts.count
default:
return 0
}
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let selectedIndex = self.searchTypeSegmentControl.selectedSegmentIndex
switch selectedIndex
{
case 0:
return tableView.dequeueReusableCell(withIdentifier: "penpalSearchReuse", for: indexPath)
case 1:
return tableView.dequeueReusableCell(withIdentifier: "statusSearchReuse", for: indexPath)
case 2:
return tableView.dequeueReusableCell(withIdentifier: "imageSearchReuse", for: indexPath)
case 3:
return tableView.dequeueReusableCell(withIdentifier: "videoSearchReuse", for: indexPath)
default:
return UITableViewCell()
}
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 420
}
}
Use selectedSegmentIndex property of UISegmentedControl to handle the UITableViewDataSource according to the selected segment.
Example:
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
let selectedIndex = self.segmentedControl.selectedSegmentIndex
switch selectedIndex
{
case 0:
return peopleArray.count
case 1:
return imagesArray.count
//Add other cases here
default:
return 0
}
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let selectedIndex = self.segmentedControl.selectedSegmentIndex
switch selectedIndex
{
case 0:
return tableView.dequeueReusableCell(withIdentifier: "peopleCell", for: indexPath) //Do your custom handling whatever required.
case 1:
return tableView.dequeueReusableCell(withIdentifier: "imageCell", for: indexPath)
//Add other cases here
default:
return UITableViewCell()
}
}
#IBAction func onChangeSegment(_ sender: UISegmentedControl)
{
self.tableView.reloadData()
}
Pretty simple Make a table array i.e common data source for tableView and create 4 array in which actual data is there. Now on each segment tap call like
On Tap of 1st Segment
tableArray = segment_1_Array
tableView.reloadData()
On Tap of 2nd Segment
tableArray = segment_2_Array
tableView.reloadData()
and so on..
In cellForRow Delegate Method there will be switch statement
let modelObj = tableArray[indexpath.row]
let cellID = ""
switch modelObj {
case _ as CellModelType1 : cellID = "CellType1Identifier"
case _ as CellModelType2 : cellID = "CellType2Identifier"
case _ as CellModelType3 : cellID = "CellType3Identifier"
case _ as CellModelType4 : cellID = "CellType4Identifier"
}
let cell = tableView.dequeueReusableCell(withIdentifier: cellID) as! TableCell
return cell
NOTE
1. TableCell will be the SuperClass and all 4 cells will be child class if this class
2. CellModelType1, CellModelType2, CellModelType3, CellModelType4
are different cell Models for example it can be
PeopleCellModel , PostsCellModel, ImagesCellModel and VideoCellModel
Hence you don't have to manage number of rows
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return tableArray.count
}
You could use a construct like this:
let people = ["pe1", "pe2", "pe3"]
let post = ["po1", "po2", "po3"]
let images = ["im1", "im2", "im3"]
let video = ["vi1", "vi2", "vi3"]
var selectedDataSource: [String] {
switch segmentedControl.selectedSegmentIndex {
case 0: return people
case 1: return post
case 2: return images
case 3: return video
default: return []
}
}
Then you can use selectedDataSource in all your tableview datasource methods. Of course you have to reload the tableview when the user changes the selection.
You will need to create a IBAction that will be fired on valueChanged event:
#IBAction func segmentChange(_ sender: UISegmentedControl) {
var nibToLoad = UINib()
switch sender.selectedSegmentIndex {
case 0:
nibToLoad = UINib(nibName: "peopleNib", bundle: Bundle.main)
tableViewDataSourceArray = PeopleArray
case 1:
nibToLoad = UINib(nibName: "postNib", bundle: Bundle.main)
tableViewDataSourceArray = PostArray
case 2:
nibToLoad = UINib(nibName: "imageNib", bundle: Bundle.main)
tableViewDataSourceArray = ImageArray
case 3:
nibToLoad = UINib(nibName: "videoNib", bundle: Bundle.main)
tableViewDataSourceArray = VideoArray
default:
//default action
}
tableView.register(nibToLoad, forCellReuseIdentifier: "identifier")
tableView.reloadData()
}
You would then make sure all of your UITableViewDelegate and UITableViewDataSource methods are using your tableViewDataSourceArray (whatever you are calling that variable).

Making table view section expand swift

I am following this tutorial for expanding and collapsing my table view section. As this demo is done in swift 2.2 I have made all the changes according to swift 3.0 . I am stuck at the below function at if condition(currentSectionCells[row]["isVisible"]) which gives me error as "Type 'NSFastEnumerationIterator.Element' (aka 'Any' has no subscript members)'".
func getIndicesOfVisibleRows() {
visibleRowsPerSection.removeAll()
for currentSectionCells in cellDescriptors {
var visibleRows = [Int]()
for row in 0...((currentSectionCells as! [[String: AnyObject]]).count - 1) {
if currentSectionCells[row]["isVisible"] as! Bool == true {
visibleRows.append(row)
}
}
visibleRowsPerSection.append(visibleRows)
}
}
I have tried type casting it as below
func getIndicesOfVisibleRows() {
visibleRowsPerSection.removeAll()
for currentSectionCells in cellDescriptors {
var visibleRows = [Int]()
for row in 0...((((currentSectionCells) as? NSMutableArray)?.count)! - 1) {
let temp = [currentSectionCells][row] as? NSMutableDictionary
let temp2 = temp?["isVisible"] as! Bool
if temp2 == true {
visibleRows.append(row)
}
}
visibleRowsPerSection.append(visibleRows)
}
}
But this gives me a crash at runtime on this line "let temp2 = temp?["isVisible"] as! Bool"
Crash says "EXC_BAD_INSTRUCTION" and the temp shows as nil.
Please help guys. TIA
Table View Delegate and Data Source
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
if cellDescriptors != nil {
return cellDescriptors.count
}
else {
return 0
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return visibleRowsPerSection[section].count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let currentCellDescriptor = getCellDescriptorForIndexPath(indexPath: indexPath as NSIndexPath)
let cell = tableView.dequeueReusableCell(withIdentifier: currentCellDescriptor["cellIdentifier"] as! String, for: indexPath) as! CustomCell
if currentCellDescriptor["cellIdentifier"] as! String == "sectionCellIdentifier" {
if let primaryTitle = currentCellDescriptor["secondaryTitle"]
{
cell.sectionTitleLabel.text = primaryTitle as? String
}
}
else if currentCellDescriptor["cellIdentifier"] as! String == "shortAnswerCell" {
cell.questionTitle.text = currentCellDescriptor["primaryTitle"] as? String
cell.questionTextView.text = currentCellDescriptor["secondaryTitle"] as? String
cell.answerTextView.text = currentCellDescriptor["answerTitle"] as? String
}
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let indexOfTappedRow = visibleRowsPerSection[indexPath.section][indexPath.row]
let temp = cellDescriptors[indexPath.section] as? NSArray
let temp2 = temp?[indexOfTappedRow ] as? NSDictionary
let temp3 = temp2?["isExpandable"] as! Bool
if temp3 == true {
var shouldExpandAndShowSubRows = false
if temp3 == false {
// In this case the cell should expand.
shouldExpandAndShowSubRows = true
}
temp2?.setValue(shouldExpandAndShowSubRows, forKey: "isExpanded")
for i in (indexOfTappedRow + 1)...(indexOfTappedRow + (temp2?["additionalRows"] as! Int)) {
(temp![i] as AnyObject).setValue(shouldExpandAndShowSubRows, forKey: "isVisible")
}
}
getIndicesOfVisibleRows()
tblExpandable.reloadSections(NSIndexSet(index: indexPath.section) as IndexSet, with: UITableViewRowAnimation.fade)
}
I worked on that tutorial as well and completed it successfully in swift3.Your solution is given below modify accordingly.
class yourClass: UIViewController
{
#IBOutlet weak var profileTableView: UITableView!
internal var visibleRowsPerSection = [[Int]]()
internal var cellDescriptors: NSMutableArray!
// VIEW DID LOAD
override func viewDidLoad() {
super.viewDidLoad()
profileTableView.showsVerticalScrollIndicator = false
loadProfileControllerData()
profileTableSetUp()
// Do any additional setup after loading the view.
}
func loadProfileControllerData(){
if let path = Bundle.main.path(forResource: "CellDescriptor", ofType: "plist") {
cellDescriptors = NSMutableArray(contentsOfFile: path)
}
getIndicesOfVisibleRows()
profileTableView.reloadData()
}
// SHOW PARENT VISIBLE ROWS AND SAVE THERE ROW INDEX IN ARRAY
func getIndicesOfVisibleRows() {
visibleRowsPerSection.removeAll()
for currentSectionCells in cellDescriptors.objectEnumerator().allObjects as! [[[String:Any]]]{
var visibleRows = [Int]()
for row in 0..<currentSectionCells.count {
if currentSectionCells[row]["isVisible"] as! Bool == true {
visibleRows.append(row)
}
}
visibleRowsPerSection.append(visibleRows)
print(visibleRowsPerSection)
}
}
// GET REQUIRED OBJECT OF TYPE [String: Any]
func getCellDescriptorForIndexPath(indexPath: NSIndexPath) -> [String: Any] {
let indexOfVisibleRow = visibleRowsPerSection[indexPath.section][indexPath.row]
let cellDescriptorss = cellDescriptors[indexPath.section] as! NSArray
let data = cellDescriptorss.object(at: indexOfVisibleRow) as! [String:Any]
return data
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
//----------------------
// EXTENSION TO OUR PROFILE CLASS THAT DETERMINE OUR CLASS CONFIRM 2 IMPORTANT DELEGATES
extension profileViewController : UITableViewDelegate,UITableViewDataSource{
//MARK-: TABLE VIEW DELEGATE FUNCTIONS
// RETURN NUMBER OF SECTION IN TABLE VIEW
public func numberOfSections(in tableView: UITableView) -> Int{
if cellDescriptors.count != 0{
return cellDescriptors.count
}
else{
return 0
}
}
// RETURN NUMBER OF ROWS IN EACH SECTION OF TABLE VIEWS
public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int{
return visibleRowsPerSection[section].count
}
/* Return object of UITableViewCell that contains table SECTON data and USER profile data */
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell{
let currentCellDescriptor = getCellDescriptorForIndexPath(indexPath: indexPath as NSIndexPath)
let menuCell = tableView.dequeueReusableCell(withIdentifier: currentCellDescriptor["cellIdentifier"] as! String, for: indexPath) as! yourCellClass
if currentCellDescriptor["cellIdentifier"] as! String == "parent"{
}
else if currentCellDescriptor["cellIdentifier"] as! String == "child"{
menuCell.backgroundColor = UIColor.clear
}
return menuCell
}
public func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
let indexOfTappedRow = visibleRowsPerSection[indexPath.section][indexPath.row]
let cellDescriptorss = cellDescriptors[indexPath.section] as! NSArray
var data = cellDescriptorss.object(at: indexOfTappedRow) as! [String:Any]
if data["isExpandable"] as! Bool == true{
var shouldExpandAndShowSubRows = false
if data["isExpanded"] as! Bool == true{
shouldExpandAndShowSubRows = false
(cellDescriptorss[indexOfTappedRow] as AnyObject).setValue(shouldExpandAndShowSubRows, forKey: "isExpanded")
}
for i in (indexOfTappedRow + 1)...(indexOfTappedRow + (data["additionalRows"] as! Int)) {
(cellDescriptorss[i] as AnyObject).setValue(shouldExpandAndShowSubRows, forKey: "isVisible")
}
}
getIndicesOfVisibleRows()
self.profileTableView.reloadSections(NSIndexSet(index: indexPath.section) as IndexSet, with: UITableViewRowAnimation.fade)
}
Thank You for helping me out, I was stuck at a point where the sections weren't expanding even after your help, so just made some changes in the syntax as Swift 3.0 is very specific about type casting hence the didSelectRowAt wasn't functioning properly. Here is the complete didSelectRowAt method. Happy coding.
public func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
let indexOfTappedRow = visibleRowsPerSection[indexPath.section][indexPath.row]
if (cellDescriptors[indexPath.section] as! [[String: AnyObject]])[indexOfTappedRow] ["isExpandable"] as! Bool == true {
var shouldExpandAndShowSubRows = false
if (cellDescriptors[indexPath.section] as! [[String: AnyObject]])[indexOfTappedRow]["isExpanded"] as! Bool == false {
// In this case the cell should expand.
shouldExpandAndShowSubRows = true
}
((cellDescriptors[indexPath.section] as! NSMutableArray)[indexOfTappedRow] as AnyObject).setValue(shouldExpandAndShowSubRows, forKey: "isExpanded")
for i in (indexOfTappedRow + 1)...(indexOfTappedRow + ((cellDescriptors[indexPath.section] as! [[String: AnyObject]])[indexOfTappedRow]["additionalRows"] as! Int)) {
((cellDescriptors[indexPath.section] as! NSMutableArray)[i] as AnyObject).setValue(shouldExpandAndShowSubRows, forKey: "isVisible")
}
}
Swift 3/4 without use of NSMutable arrays based on the tutorial and all the code wrapped in a model.
class CellsDescriptorModel {
private var cellDescriptors: [[[String:Any]]]!
private var visibleRowsPerSection : [[Int]]
var CellDescriptors : [[[String:Any]]] { get { return cellDescriptors }}
var VisibleRowsPerSection : [[Int]] { get { return visibleRowsPerSection }}
init(plist:String) {
visibleRowsPerSection = [[Int]]()
if let url = Bundle.main.url(forResource:plist, withExtension: "plist") {
do {
let data = try Data(contentsOf:url)
cellDescriptors = try PropertyListSerialization.propertyList(from: data, options: [], format: nil) as! [[[String:Any]]]
} catch {
print(error)
}
}
getIndicesOfVisibleRows()
}
func getCellDescriptorForIndexPath(indexPath: IndexPath) -> [String: Any] {
let indexOfVisibleRow = visibleRowsPerSection[indexPath.section][indexPath.row]
return cellDescriptors[indexPath.section][indexOfVisibleRow]
}
func expandCell(indexPath:IndexPath) {
let indexOfTappedRow = visibleRowsPerSection[indexPath.section][indexPath.row]
if cellDescriptors[indexPath.section][indexOfTappedRow] ["isExpandable"] as! Bool == true {
var shouldExpandAndShowSubRows = false
if cellDescriptors[indexPath.section][indexOfTappedRow]["isExpanded"] as! Bool == false {
shouldExpandAndShowSubRows = true
}
cellDescriptors[indexPath.section][indexOfTappedRow]["isExpanded"] = shouldExpandAndShowSubRows
for i in (indexOfTappedRow + 1)...(indexOfTappedRow + (cellDescriptors[indexPath.section][indexOfTappedRow]["additionalRows"] as! Int)) {
cellDescriptors[indexPath.section][i]["isVisible"] = shouldExpandAndShowSubRows
}
}
else {
if cellDescriptors[indexPath.section][indexOfTappedRow]["cellIdentifier"] as! String == "DataPickerTableViewCell" {
var indexOfParentCell: Int!
for index in (0..<indexOfTappedRow).reversed() {
if cellDescriptors[indexPath.section][index]["isExpandable"] as! Bool == true {
indexOfParentCell = index
break
}
}
cellDescriptors[indexPath.section][indexOfParentCell]["secondaryTitle"] = ""
cellDescriptors[indexPath.section][indexOfParentCell]["isExpanded"] = false
for i in (indexOfParentCell + 1)...(indexOfParentCell + (cellDescriptors[indexPath.section][indexOfParentCell]["additionalRows"] as! Int)) {
cellDescriptors[indexPath.section][i]["isVisible"] = false
}
}
}
getIndicesOfVisibleRows()
}
private func getIndicesOfVisibleRows() {
visibleRowsPerSection.removeAll()
for currentSectionCells in cellDescriptors {
var visibleRows = [Int]()
for row in 0..<currentSectionCells.count {
if currentSectionCells[row]["isVisible"] as! Bool == true {
visibleRows.append(row)
}
}
visibleRowsPerSection.append(visibleRows)
}
}
}

Execute code first! Swift

guys I am getting data from Foursquare APi and here is my code below.
But I am getting a nil error at cellForRowAtIndexPath that venueItems is nil
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
// Table View
self.tableView = UITableView()
// Location Manager Stuff
self.locationManager = CLLocationManager()
self.locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
self.locationManager.delegate = self
let status = CLLocationManager.authorizationStatus()
if status == .notDetermined {
self.locationManager.requestWhenInUseAuthorization()
} else if status == CLAuthorizationStatus.authorizedWhenInUse
|| status == CLAuthorizationStatus.authorizedAlways {
self.locationManager.startUpdatingLocation()
} else {
showNoPermissionsAlert()
}
exploreVenues()
}
// Func's
func exploreVenues() {
guard let location = self.locationManager.location else {
return
}
var parameters = [Parameter.query: "Pubs"]
parameters += location.parameters()
let task = self.session.venues.explore(parameters) {
(result) -> Void in
if self.venueItems != nil {
return
}
if !Thread.isMainThread {
fatalError("!!!")
}
if let response = result.response {
if let groups = response["groups"] as? [[String: AnyObject]] {
var venues = [[String: AnyObject]]()
for group in groups {
if let items = group["items"] as? [[String: AnyObject]] {
venues += items
}
}
self.venueItems = venues
}
self.tableView.reloadData()
} else if let error = result.error, !result.isCancelled() {
self.showErrorAlert(error)
}
}
task.start()
}
// Table View Data source
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if let venueItems = self.venueItems {
return venueItems.count
}
return 10
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! VenueTableViewCell
// This is where the error occurs
let item = self.venueItems![(indexPath as NSIndexPath).row] as JSONParameters!
self.configureCellWithItem(cell, item: item!)
return cell
}
func configureCellWithItem(_ cell: VenueTableViewCell, item: JSONParameters) {
if let venueInfo = item["venue"] as? JSONParameters {
cell.nameLabel.text = venueInfo["name"] as? String
}
}
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
let cell = cell as! VenueTableViewCell
let tips = self.venueItems![(indexPath as NSIndexPath).row]["tips"] as? [JSONParameters]
guard let tip = tips?.first, let user = tip["user"] as? JSONParameters,
let photo = user["photo"] as? JSONParameters else {
return
}
let URL = photoURLFromJSONObject(photo)
if let imageData = session.cachedImageDataForURL(URL) {
cell.venueImageView.image = UIImage(data: imageData)
} else {
cell.venueImageView.image = nil
session.downloadImageAtURL(URL) { (imageData, error) -> Void in
let cell = tableView.cellForRow(at: indexPath) as? VenueTableViewCell
if let cell = cell, let imageData = imageData {
let image = UIImage(data: imageData)
cell.venueImageView.image = image
}
}
}
}
}
I am quite new to programming personally I think that the venueItems is nil because the cellForRowAtIndexPath is being executed first. If this is the error how can I fix it so the code in cellForRowAtIndexpath runs after my venueItems has a value.. or any other more efficient Way?
Your numberOfRowsInSection returns 10 when self.venueItems is nil. self.venueItems appears to be nil until your network request finishes so the table view, having been told it has 10 rows to display asks for a cell for each row. You then attempt to force unwrap an optional property (self.venueItems!) and crash.
It looks like your self.venueItems is an optional for good reason, don't discard that information with a force unwrap (!). You could either return 0 rows when this property is nil or initialize it to a non-optional empty array which you could then always ask for its count.
In general with this sort of problem you don't want to focus on preventing cellForRowAtIndexPath from being called but rather plan for it to be called at any point and return a reasonable result (like reporting that the table has 0 rows) when your background tasks haven't finished yet.

Fetch data from Firebase Database to tableview

First I get these values into my Firebase Database, which works successfully.
func handleSale() {
let ref = FIRDatabase.database().reference().child("tickets")
let childRef = ref.childByAutoId()
guard let Price = emailTextField.text, ticketName = passwordTextField.text else {
print("Form is not valid")
return
}
let values: [String: AnyObject] = ["Price": Price, "ticketName": ticketName]
ref.observeEventType(.ChildAdded, withBlock: { (snapshot) in
let ticketId = snapshot.key
let ticksRef = FIRDatabase.database().reference().child("tickets").child(ticketId)
ticksRef.observeSingleEventOfType(.Value, withBlock: { (snapshot) in
guard let dictionary = snapshot.value as? [String: AnyObject] else {
return
}
self.messages.append(Ticket(dictionary: dictionary))
childRef.updateChildValues(values) { (error, ref) in
if error != nil {
print(error)
return
}
print(snapshot)
print(dictionary)
print(ticketId)
}
}, withCancelBlock: nil)
})
}
I then tried to setup a tableview with a custom cell class and fetch these values into the tableview, however being fairly new to swift, I know I haven't done this correctly. In the end I would like that my values "price" and "ticketName" shows up in my table's..
here is my tableview:
import UIKit
import Firebase
class Sales: UITableViewController {
let cellId = "cellId"
var messages = [Ticket]()
var messagesDictionary = [String: Ticket]()
override func viewDidLoad() {
super.viewDidLoad()
var messages = [Ticket]()
var messagesDictionary = [String: Ticket]()
navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Logout", style: .Plain, target: self, action: #selector(heya))
tableView.registerClass(FredericCell.self, forCellReuseIdentifier: cellId)
func fetchTicket() {
FIRDatabase.database().reference().child("tickets").observeEventType(.ChildAdded, withBlock: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let ticketId = snapshot.key
Ticket.setValuesForKeysWithDictionary(dictionary)
return
}
}, withCancelBlock: nil)
}
print("test to see if it works")
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 5
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier(cellId, forIndexPath: indexPath) as! FredericCell
return cell
}
func heya() {
print ("working")
}
I have edited in hope of filling out my cells, but without luck..:
override func tableView(tableView: UITableView,
numberOfRowsInSection section: Int) -> Int {
return tickets
.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier(cellId, forIndexPath: indexPath) as! FredericCell
let ticket = tickets[indexPath.row]
cell.textLabel?.text = ticket.ticketName
cell.detailTextLabel?.text = ticket.Price
dispatch_async(dispatch_get_main_queue(), {
self.tableView.reloadData()
})
return cell
}

Resources