How to pass data in selected cell to another view controller? - ios

The piece of code below prints the content of whichever cell is clicked on in my TableView.
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print(self.cell[indexPath.row])
}
I want to use the result that is printed in a label on another ViewController.
How do I get the string value from the function and then use it on on the other view? My thought is to use a global variable but I need to get the string value out first.

For example, You can use simple organization of a singleton of another ViewController (SecondScreen) with var main (in case, as usual, when SecondScreen inited via a Storyboard):
class SecondScreen : UIViewController {
// 1. add this var
static var main : SecondScreen? = nil
// 2. Your some UI element
#IBOutlet weak var textButton: UIButton!
// 3. add this method
func updateUI(string : String) {
textButton.setTitle(string, for: .normal)
}
// 4. setting a var
override func viewDidLoad() {
if SecondScreen.main == nil {
SecondScreen.main = self
}
}
// ... another your and standard methods
}
And you can update your SecondScreen like this:
let v = SecondScreen.main
v?.updateUI(string: "yourString")
Also I recommend you to call method async:
DispatchQueue.main.async {
SecondScreen.main?.updateUI(withString : string)
}
I suggest you to learn more about singletons...

At first, when you create a tableView, you have to collect data (string here) of cells in an array or another data collection. And you can get a needed data (strings) with indexPath variable in the method didSelectRowAt. And you can pass the string to another ViewController (let use SecondViewController) with several ways.
Here is an example:
// declaration an array of your strings
var array : [String] = ["First", "Second", "Third", ...]
...
// getting a string from method:
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let string = array[indexPath.row]
print(string)
// next, for example, you need to pass the string to a singleton SecondViewController with static var **main**:
SecondViewController.main?.neededString = string
}
Don't forget update in async DispatchQueue:
DispatchQueue.main.async {
SecondViewController.main?.updateUI(withString : string)
}

Related

How can I save the state of UISwitches on a TableViewController when navigating through different view controllers/table view controllers?

My checklist application has different sections where the main screen (UIViewController) with several buttons leading to various food items (Vegetables, Fruits, etc.). The buttons lead to a TableViewController page, where you can add items via "+" button that modally presents an "Add Item" view controller.
After adding items to the list, it puts the name of the item and a UISwitch at the far right. This switch represents the check part of the checklist. However, regardless of what state you leave it on, when you navigate between different subsections (like going from Vegetables List -> Home -> Fruits List -> Home -> Back to Vegetables List) and come back to the original list, all the switches are off.
I have an idea of what I have to do: UserDefaults. My idea is to store the state of the switch when the state is changed and then in the viewDidLoad function iterate through all visible elements and set the state of the switches to their saved states. However, I'm not sure where to start with this idea.
Snapshot of a portion of my storyboard that depicts the design for my list area and my add items area
The list TableViewController is linked to a class called MEListViewController. Problem here is when I try to make an outlet in the ViewController class, it says that
I'm not allowed to put Outlets on repeating objects.
So, How can I save the state of Switches and keep them in their user-selected state even when you navigate through different screens?
Currently switches can be toggled while looking at a list. Leave the list and come back to it and the switches are reverted to the default "OFF" state.
To address your this problem
"it says that I'm not allowed to put Outlets on repeating objects."
You need have a custom UITableViewCell class and then you can have UISwitch outlet there.
Then to save a UISwitch state for further use
You can store only the selected cell index as state in UserDefault and check the same against the current index in cellForRowAt tableView method.
If it is found then your last state is ON otherwise default one is OFF.
This code snippet will work as you expect:
Custom UITableViewCell class
class CustomCell: UITableViewCell {
#IBOutlet weak var switchObj: UISwitch!
#IBOutlet weak var textValue: UILabel!
#IBAction func toggleState(_ sender: Any) {
var loadValues: [Int: Bool]!
if let values = Memory.getStatesFromMemory() {
loadValues = values
} else {
loadValues = [Int: Bool]()
}
loadValues[switchObj.tag] = switchObj.isOn
Memory.saveSwitchStatesToMemory(savedStates: loadValues)
}
}
UIViewController class
class CustomTableView: UIViewController, UITableViewDelegate, UITableViewDataSource {
var savedStates: [Int: Bool]!
override func viewDidLoad(){
super.viewDidLoad()
if let values = Memory.getStatesFromMemory() {
savedStates = values
} else {
savedStates = [Int: Bool]()
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 10
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "CustomCell") as? CustomCell
cell?.switchObj.isOn = savedStates[indexPath.row] == nil ? false : savedStates[indexPath.row]!
cell?.switchObj.tag = indexPath.row
cell?.textValue.text = "Switch stored state >>"
return cell!
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 80
}
}
Custom class to use for save/retrieve values from memory
class Memory {
static func getStatesFromMemory() -> [Int: Bool]? {
if let switchValues = UserDefaults.standard.object(forKey: "SwitchStates") as? Data {
let decodedTeams = NSKeyedUnarchiver.unarchiveObject(with: switchValues) as! [Int: Bool]
return decodedTeams
}
return nil
}
static func saveSwitchStatesToMemory(savedStates: [Int: Bool]) {
let encodedData = NSKeyedArchiver.archivedData(withRootObject: savedStates)
let userDefaults = UserDefaults.standard
userDefaults.set(encodedData, forKey: "SwitchStates")
UserDefaults.standard.synchronize()
}
}
For a simple implementation you could have an array of Item objects (below). When you toggle a switch, figure out which cell's switch was toggled, then update the isOn state in the corresponding Item.
When you dequeue a cell before displaying it, make sure to update the UISwitch's state based on the value of the corresponding Item.
Here's a basic item class that can get you started.
class Item {
var isOn: Bool
}

How to add multiple data to a UITableView from a UITextField? (SWIFT 4)

I am trying to create a program on Xcode that allows the user to enter multiple data into a table view through a text field (when a button is clicked). When the data is added I would like it to be stored and not be deleted after the app is closed - for this part I believe that I would have to use NSUserDefaults, however, I am unsure how I would save an array of strings? (I'm only familiar with storing a single string).
This is what my view controller currently looks like.
I have not done much on my view controller at all but this is what it currently has.
import UIKit
class NewViewController: UIViewController {
#IBOutlet weak var text: UITextField!
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*
// 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.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}
Let's tackle this step-by-step...
TL;DR - For your convenience, I've put the final code into a sample project on Github. Feel free to use any or all of the code in your apps. Best of luck!
Step 1 - Conform to UITableView Protocols
"...enter multiple data into a table view..."
At a minimum, UITableView requires you to conform to two protocols in order to display data: UITableViewDelegate and UITableViewDataSource. Interface Builder handles the protocol declaration for you if you use the built-in UITableViewController object, but in your case you cannot use that object because you only want the UITableView to take up a portion of the view. Therefore, you must implement the protocols yourself by adding them to ViewController's signature:
Swift 4
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
}
Step 2 - Implement UITableView Protocol Required Methods
Now that you have the protocols declared, Xcode displays an error until three required methods are implemented inside of your ViewController class. The bare minimum implementation for these methods is:
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 0
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
return UITableViewCell()
}
You'll implement these methods later, but at this point your code should compile.
Step 3 - Connect UITableView's Protocols to ViewController
Since you are using a standard UITableView object, ViewController is not connected by default to the code you just implemented in the protocol methods. To make a connection, add these lines to viewDidLoad():
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
}
Alternatively, you could use the CONTROL + DRAG technique in Interface Builder to connect the delegate and data source from your UITableView to ViewController.
NOTE: In this case, self refers to the ViewController since you're inside of the ViewController class.
Step 4 - UITextField Setup
"...through a text field..."
You previously added an IBOutlet for your UITextField that is connected to Interface Builder, so there is nothing more to do here.
Step 5 - IBAction for the Add Button
(when a button is clicked)."
You need to add an IBAction to your ViewController class and connect it to your Add Button in Interface Builder. If you prefer to write code and then connect the action, then add this method to your ViewController:
#IBAction func addButtonPressed(_ sender: UIButton) {
}
If you use Interface Builder and the CONTROL + DRAG technique to connect the action, the method will be added automatically.
Step 6 - Add an Array Property to Store Data Entries
"...save an array of strings..."
You need an array of strings to store the user's entries. Add a property to ViewController that is initialized as an empty array of strings:
var dataArray = [String]()
Step 7 - Finish Implementing UITableView Protocol Methods
At this point you have everything you need to finish implementing UITableView's protocol methods. Change the code to the following:
//1
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
//Do nothing
}
//2
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return dataArray.count
}
//3
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
cell.textLabel?.text = dataArray[indexPath.row]
return cell
}
In the future, if you want to do something when the user taps a cell, you will want to add code to tableView(_:didSelectRowAt:).
You now create the same number of rows as the number of values in dataArray.
To make this work with Interface Builder, make sure you go to the Attributes Inspector for your UITableViewCell and set the Cell Identifier to Cell. Check out the documentation for more on Dequeuing Cells.
Step 8 - Finish Implementing addButtonPressed(_:)
As suggested in #dani's answer, in the action you need to implement code that appends the user's text to the array, but only if the text is not blank or empty. It is also a good idea to check if dataArray already contains the value you entered using dataArray.contains, depending on what you want to accomplish:
if textField.text != "" && textField.text != nil {
let entry = textField.text!
if !dataArray.contains(entry) {
dataArray.append(entry)
textField.text = ""
}
tableView.reloadData()
}
Step 9 - Persist Data with UserDefaults
"When the data is added I would like it to be stored and not be deleted after the app is closed."
To save dataArray to UserDefaults, add this line of code after the line that appends an entry inside of the addButtonPressed(_:) action:
UserDefaults.standard.set(dataArray, forKey: "DataArray")
To load dataArray from UserDefaults, add these lines of code to viewDidLoad() after the call to super:
if let data = UserDefaults.standard.value(forKey: "DataArray") as? [String] {
dataArray = data
}
Try the following:
Create an array that will store all the text entered via the UITextField (ie. var array = [String]()
In the action of that add button, append the text the user has entered in the text field to the array.
if text.text != "" && !text.text.isEmpty {
// append the text to your array
array.append(text.text!)
text.text = "" // empty the `UITextField`
}
In your tableView methods, make the numberOfRows return array.count and just add a UILabel for your custom UITableViewCell that will display each entered item from the array in a separate cell.
if you want to display your data in tableview you need to implement tableview delegates. add a table view cell with a label on it
#IBOutlet weak var text: UITextField!
#IBOutlet weak var tableView: UITableView!
let NSUD_DATA = "dataarray_store"
var dataArray : NSMutableArray!
var userDefault = UserDefaults.standard
override func viewDidLoad() {
super.viewDidLoad()
dataArray = NSMutableArray()
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
//MARK:- create a button for adding the strings to array and while clicking that button
func onClickButton(){
let string = text.text
dataArray.add(string)
userDefault.set(dataArray, forKey: NSUD_DATA)
}
for getting array stored in userdefault
func getData() -> NSMutableArray?{
if userDefault.object(forKey: NSUD_DATA) != nil{
return userDefault.array(forKey: NSUD_DATA) as! NSMutableArray
}
return nil
}
class ViewController: UIViewController,UITableViewDelegate,UITableViewDataSource {
#IBOutlet weak var entertxt: UITextField!
#IBOutlet weak var save: UIButton!
#IBOutlet weak var tableview: UITableView!
var names = [String]()
override func viewDidLoad() {
super.viewDidLoad()
if let data = UserDefaults.standard.object(forKey: "todolist") as?[String]
{
names = data
}
}
#IBAction func submit(_ sender: Any) {
if entertxt.text != "" {
names.append(entertxt.text!)
UserDefaults.standard.set(names, forKey: "todolist")
tableview.reloadData()
entertxt.text = ""
}
else
{
print("data not found")
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return names.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! myTableViewCell
cell.namelable.text = names[indexPath.row]
return cell
}

Swift retain UISegmentedControl values in UITableViewCells

I'm creating a quiz app with custom cells that include a label of questions and then an answer coming from a UISegmentedControl.
The values of the segmentedcontrols get changed when scrolling and this leads to an inaccurate score. I understand that this is due to UITableView reusing cells.
My tableview's datasource in my main vc is simply the labels for all my questions coming from a plist file.
The code for my custom tableviewcell class is
class QuestionsTableViewCell: UITableViewCell {
#IBOutlet weak var questionLabel: UILabel!
#IBOutlet weak var selection: UISegmentedControl!
var question: String = "" {
didSet {
if (question != oldValue) {
questionLabel.text = question
}
}
}
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
//Just for testing
#IBAction func segmentChanged(_ sender: UISegmentedControl) {
print("value is ", sender.selectedSegmentIndex);
}
}
where the View is stored in an .XIB file.
And the code for my main vc is
class ViewController: UIViewController, UITableViewDataSource {
let questionsTableIdentifier = "QuestionsTableIdentifier"
#IBOutlet var tableView:UITableView!
var questionsArray = [String]();
var questionsCellArray = [QuestionsTableViewCell]();
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
let path = Bundle.main.path(forResource:
"Questions", ofType: "plist")
questionsArray = NSArray(contentsOfFile: path!) as! [String]
tableView.register(QuestionsTableViewCell.self,
forCellReuseIdentifier: questionsTableIdentifier)
let xib = UINib(nibName: "QuestionsTableViewCell", bundle: nil)
tableView.register(xib,
forCellReuseIdentifier: questionsTableIdentifier)
tableView.rowHeight = 108;
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return questionsArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(
withIdentifier: questionsTableIdentifier, for: indexPath)
as! QuestionsTableViewCell
let rowData = questionsArray[indexPath.row]
cell.question = rowData
return cell
}
#IBAction func calculate(_ sender: UIButton) {
var score = 0
for cell in tableView.visibleCells as! [QuestionsTableViewCell] {
score += cell.selection.selectedSegmentIndex
}
let msg = "Score is, \(score)"
print(msg)
}
#IBAction func reset(_ sender: UIButton) {
for cell in tableView.visibleCells as! [QuestionsTableViewCell] {
cell.selection.selectedSegmentIndex = 0;
}
}
}
What I'd like to do is just keep track of all 'selection' changes of the Questions cells in an array, and then use that array in cellForRowAt. I'm just confused as to how i can dynamically keep track of changes from a view in another class. I'm new to Swift and would like to solve this is a proper MVC fashion. Thanks
Instead of a simple string array as data source create a class holding the text and the selected index
class Question {
let text : String
var answerIndex : Int
init(text : String, answerIndex : Int = 0) {
self.text = text
self.answerIndex = answerIndex
}
}
Declare questionArray as
var questions = [Question]()
Populate the array in viewDidLoad with
let url = Bundle.main.url(forResource: "Questions", withExtension: "plist")!
let data = try! Data(contentsOf: url)
let questionsArray = try! PropertyListSerialization.propertyList(from: data, format: nil) as! [String]
questions = questionsArray.map {Question(text: $0)}
In the custom cell add a callback and call it in the segmentChanged method passing the selected index, the property question is not needed, the label is updated in cellForRow of the controller
class QuestionsTableViewCell: UITableViewCell {
#IBOutlet weak var questionLabel: UILabel!
#IBOutlet weak var selection: UISegmentedControl!
var callback : ((Int) -> ())?
#IBAction func segmentChanged(_ sender: UISegmentedControl) {
print("value is ", sender.selectedSegmentIndex)
callback?(sender.selectedSegmentIndex)
}
}
In cellForRow add the callback and update the model in the closure
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: questionsTableIdentifier, for: indexPath) as! QuestionsTableViewCell
let question = questions[indexPath.row]
cell.questionLabel.text = question.text
cell.selection.selectedSegmentIndex = question.answerIndex
cell.callback = { index in
question.answerIndex = index
}
return cell
}
To reset the segmented controls in the cells set the property in the model to 0 and reload the table view
#IBAction func reset(_ sender: UIButton) {
questions.forEach { $0.answerIndex = 0 }
self.tableView.reloadData()
}
Now you could calculate the score directly from the model instead of the view.
Don't try to use cells to hold information. As the user scrolls through your table view, cells that scroll out of view will get recycled and their field settings will be lost. Also, newly dequeued cells will have the settings from the last time they were used.
You need to refactor your code to read/write information into a data model. Using an array of Structs as a data model is a reasonable way to go. (Or, as vadian suggests in his answer, and array of Class objects, so you get reference semantics.)
You have an IBAction segmentChanged() in your custom cell class. The next trick is to notify the view controller when the user changes the selection, and to update cells when you set them up in cellForRowAt.
I suggest defining a protocol QuestionsTableViewCellProtocol, and have the view controller conform to that protocol:
protocol QuestionsTableViewCellProtocol {
func userSelected(segmentIndex: Int, inCell cell: UITableViewCell)
}
}
Add a delegate property to your QuestionsTableViewCell class:
class QuestionsTableViewCell: UITableViewCell {
weak var delegate: QuestionsTableViewCellProtocol?
//The rest of your class goes here...
}
Update your cell's segmentChanged() method to invoke the delegate's userSelected(segmentIndex:inCell:) method.
In your view controller's cellForRowAt, set the cell's delegate to self.
func userSelected(segmentIndex: Int, inCellCell cell: UITableViewCell) {
let indexPath = tableView.indexPath(for: cell)
let row = indexPath.row
//The code below assumes that you have an array of structs, `dataModel`, that
//has a property selectedIndex that remembers which cell is selected.
//Adjust the code below to match your actual array that keeps track of your data.
dataModel[row].selectedIndex = segmentIndex
}
Then update cellforRowAt() to use the data model to set the segment index on the newly dequeued cell to the correct index.
Also update your calculate() function to look at the values in your dataModel to calculate the score, NOT the tableView.
That's a rough idea. I left some details out as "an exercise for the reader." See if you can figure out how to make that work.

Notify UITable from an other Thread

I've got a simple UITable implementation and an array which is called fruits. Taken out of this example. The only difference is that I am using a UIViewController for the UITable insted of a UITableViewController, but this should be irrelevant for now.
class MainViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var fruits : [String] = Array()
let thread : GetDataForFruitsArrayThread
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return fruits.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "LabelCell", for: indexPath)
cell.textLabel?.text = fruits[indexPath.row]
return cell
}
}
Now I have got a viewDidLoad function in this class also. In the function I am calling a thread which is getting the array as a parameter. The thread is filling up the array with new values asynchronously. Means I don't know if there will be any values or when do the value appear and are set into the array. So you can imagine what I want to ask on this point: How do I signal the UITableView that I have changed the content of the array once the view has loaded the array into the UITable. In c# there is the NotifyAll() function which notfies all the Listener to an attribute. Is there an easy and performant way to do this in swift, optionally without importing any non-included libraries?
override func viewDidLoad() {
super.viewDidLoad()
self.thread = GetDataForFruitsArrayThread(array: &fruits)
self.thread.StartAsynchronously()
}
EDIT - adding GetDataForFruitsArrayThread
class GetDataForFruitsArrayThread : MyThread {
var array : [String]
init(array: inout [String] ) {
self.array = array
}
override func main() {
// init socket
while(true){
_ = withUnsafeMutablePointer(to: &rcvaddr){
$0.withMemoryRebound(to: sockaddr.self, capacity: 1){
recvfrom(m_socket, &pData, bufferlength, 0, UnsafeMutablePointer($0),
&socketAddressLength)
}
}
var fruit = String(cString:inet_ntoa(rcvaddr.sin_addr), encoding: .ascii)
self.array.append(fruit)
}
}
}
EDIT - 21.11.2017:
Following Sandeep Bhandari's answer I changed the following code in the ViewController:
#IBOutlet weak var tableView1: UITableView!
var fruits : [String] = Array() {
didSet {
self.tableView1.reloadData()
}
}
PROBLEM: I am setting a breakpoint at array.append(fruit) in the GetDataForFruitsArrayThread-class. After that there is a breakpoint in the didSet method. But this breakpoint does not get called after the append()-call! NOTE: The parameter on the init function of the GetDataForFruitsArrayThread-class is an in-out parameter!
UPDATE: I found out that if I do the array.append(fruit)-call on the GetDataForFruitsArrayThread.array in the GetDataForFruitsArrayThread-thread, the Fruits-array in ViewController-class does not get changed, therefore didSet did not get called. How can I change this behaviour?
Because you said you are running a endless process to keep updating your array and you want the UI update once the array changes you can use the below solution.
var fruits : [String] = Array() {
didSet {
self.tableView.reloadData()
}
}
What am I doing ? Simple added a setter to array and whenever value changes I reload the tableView.
EDIT:
The above solution will work only if you modify the inout fruits array you pass to GetDataForFruitsArrayThread
self.thread = GetDataForFruitsArrayThread(array: &fruits)
So don't create one more array property in GetDataForFruitsArrayThread rather directly modify the array passed to GetDataForFruitsArrayThread.

How to call a table view function from within #IBAction

From within cellForRowAtIndexPath:
func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
I am creating a UITableViewCell subclass, PeopleTableViewCell:
let cell:PeopleTableViewCell = self.tv_main.dequeueReusableCellWithIdentifier("row_cell") as PeopleTableViewCell
and then I pass some parameters
cell.loadItem( param1 as NSString, p2: param2 )
Now, in each row I have a button, and when I click it
#IBAction func button_clicked( param1: NSString){
I need to call a function in the parent table that takes as an argument one of the parameters I had passed (ex param1).
How can I accomplish this?
Edit, after the answer that #rob gave:
What finally worked is to
A. Pass a reference to the the parent UIViewController to the cell.loadItem
func cell.loadItem( param1 as NSString, controller: self )
and assign the controller variable to a local variable , say pvcontroller
func loadItem(param1: String, controller: PeopleViewController) {
self.pvcontroller = controller
}
B. From within the PeopleTableViewCell class, from within the button click function, I call the function of the parent UIViewController via the pvcontroller variable
#IBAction func person_image_click(sender: UIButton) {
self.pvcontroller?.person_clicked(self.param1)
}
You could:
Have a property in PeopleTableViewCell that is updated by loadItem:
class PeopleTableViewCell : UITableViewCell {
var param1: NSString?
func loadItem(param1: NSString, param2: NSString) {
self.param1 = param1
// do your other stuff here
}
// the rest of your implementation here
}
Have your cellForRowAtIndexPath call loadItem:
override func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
let cell = tableView.dequeueReusableCellWithIdentifier("row_cell", forIndexPath: indexPath) as PeopleTableViewCell
let param1 = ...
let param2 = ...
cell.loadItem(param1, param2: param2)
return cell
}
Then your #IBAction could determine the PeopleTableViewCell instance, and access its property. Note, the #IBAction parameter, sender, references the button, like always. Thus, if this #IBAction was implemented in the table view controller, then you'd have to navigate up the view hierarchy to get to the cell, and then access the property from there:
#IBAction func buttonClicked(sender: UIButton) {
let cell = sender.superview?.superview as PeopleTableViewCell
let param1 = cell.param1
// do something with param1 now
}
In this example, I have the button on the cell's content view, so I'm going up two levels of superview (one to get the content view, one to get the cell). Just ensure that whatever you do here mirrors the hierarchy you've configured in IB.
Alternatively, you can implement your #IBAction from within the PeopleTableViewCell class, in which case you don't have use this sender.superview?.superview syntax, but rather can just reference self to get to that param1 property. It's up to you.

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