I have a UITableView that has Two ProtoType Cells both with separate TableViewCell subclassess. In one of the prototype cells I have multiple switches. The user can select the item they want in the table and turn the switch on that corresponds to the item. I would like to be able to store the UISwitchstate so if the user navigates away and comes back they will see what they have selected previously.
I'm trying to store the UISwitchstate in a dictionary and then call the state back when the table gets reloaded.
Here is the code I have so far:
#IBAction func switchState(sender: AnyObject) {
if mySwitch.on{
savedItems = NSMutableDictionary(object: mySwitch.on, forKey: "switchKey")
standardDefaults.setObject("On", forKey: "switchKey")
}
else{
standardDefaults.setObject("Off", forKey: "switchKey")
and then this is in the awakeNib section:
override func awakeFromNib() {
super.awakeFromNib()
self.mySwitch.on = NSUserDefaults.standardUserDefaults().boolForKey("switchKey")
NSUserDefaults.standardUserDefaults().registerDefaults(["switchKey" : true])
}
thanks for the help.
What you need to do is:
Having a dictionary (or any other data type) that is from the exact same size as your data source.
And in your
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
you need to that dictionary for the row indexPath.row and then mainpulate your cell
Note, your dictionary should be static
Putting my answer here instead of a comment so I can hopefully explain things better. You need to have some sort of system to keep up with which dictionary item corresponds with which UISwitch. Your best bet would probably be to have a dictionary var uiDictionary = [String : Bool]() where your keys are a string that you know corresponds to a specific switch. Then, in your cellForRowAtIndexPath: you would try to access each dictionary item, check if it's the one for the switch you're trying to set, and then set it. Don't know your exact setup, but it would look something like this...
func cellForRowAtIndexPath() {
//other stuff here
//now set your switches
for (key, value) in uiDictionary {
switch(key) {
case "Switch1":
if value == true {
cell?.switch1.setOn(true, animated: true)
} else {
cell?.switch1.setOn(false, animated: true)
}
break
case "Switch2":
if value == true {
cell?.switch1.setOn(true, animated: true)
} else {
cell?.switch1.setOn(false, animated: true)
}
}
}
}
Related
I have a ProductVC.swift (ProductViewController) file and a ProductCell.swift. The ProductVC contains a UICollectinView and ProductCell is a specific UICollectionViewCell.
ProductCell.xib looks like this:
ProductVC contains an array with all the cell data (products) and populates the cells.
My goal: The user should have the possibility to like an product. He can do it by clicking the like button on the top right corner of every cell. Every cell shows a specific product which is specified by a productID.
My Problem: The like button action (IBAction func) is in the ProductCell. ProductCell doesn´t have the cell data. Cell data is stored in ProductVC in an array. So I don´t know how catch the product(productID) the user wants to like.
My Tries: With the code below I can get the indexPath of the cell where the user clicked the like button. But I can´t use this indexPath to get the product data because the data is stored in ProductVC. I could also store the data in ProductCell but it is not a clean way. Is it possible mb to give this indexPath to the ProductVC?
extension UICollectionView {
func indexPathForView(_ view: UIView) -> IndexPath? {
let center = view.center
let viewCenter = self.convert(center, from: view.superview)
let indexPath = self.indexPathForItem(at: viewCenter)
return indexPath
}
}
let superview = self.superview as! UICollectionView
if let indexPath = superview.indexPathForView(button) {
print(indexPath) // indexPath of the cell where the button was pressed
}
SOLVED Solution is a callback closure:
//UICollectionViewCell
var saveProductLike: ((_ index: Int) -> Void)?
#IBAction func likedButtonClicked(_ sender: UIButton) {
print("Liked button clicked!")
let productArrayIndex = calculateProductArrayIndex(for: sender)
saveProductLike?(productArrayIndex!)
}
//UIViewController
cell.saveProductLike = { (index) -> Void in
print(index)
}
There are several approaches to solve this but I'll talk about the most common one which is using delegation.
protocol ProductCellDelegate: AnyObject {
func productCellDidPressLikeButton(_ cell: ProductCell)
}
in ProductCell define a property weak var delegate: ProductCellDelegate? and in the target action of the like button inform your delegate
#objc private likeButtonPressed(_ sender: Any) {
delegate?.productCellDidPressLikeButton(self)
}
In your view controller you could conform to the protocol and implement it like this:
func productCellDidPressLikeButton(_ cell: ProductCell) {
guard let ip = collectionView.indexPath(for: cell) else { return }
// process event, get product via index...
}
Then you need to set the view controller to be the delegate in collectionView(_:willDisplay:forItemAt:) or
collectionView(_:cellForItemAt:): cell.delegate = self.
I am making an app where I take in user input and display it as a chart, which requires an array of data. I have managed to save data in an array using core data and I cannot figure out how to share that data from one tab to the other TabViewController.
here is how the data is stored and fetched in the FirstViewController
let number = Numbers(context: PersistenceService.context)
number.numberInArray = Int16(numberEnteredInSlider)
PersistenceService.saveContext()
testArray.append(Int(Double(number.numberInArray)))
var numbers = [Numbers]() // Where Numbers = NSManaged Class
var fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "Numbers")
do {try numbers = PersistenceService.context.fetch(fetchRequest) as! [Numbers]
for number in numbers {
print(number.numberInArray)
}
}catch {
print("error")
}
and here is the output(printed testarray):
SAVED
2
5
6
5
Now I want to share this test array from one view controller to another(chartsViewController)
this is what I have tried
class chartsViewController: UIViewController {
let mainVC = mainViewController(nibName: "mainViewController", bundle: nil)
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
print(mainVC.testArray)
updateGraph()
func updateGraph() {
var lineChartEntry = [ChartDataEntry]() //this is the Array that will eventually be displayed on the graph.
for i in 0..<mainVC.testArray.count {
//
let value = ChartDataEntry(x: Double(i), y: Double(mainVC.testArray[i]))
// here we set the X and Y status in a data chart entry
lineChartEntry.append(value)
// here we add it to the data set
}}
//only showing the part needed. I have tried the same solution with another array and it worked.
}
and the output comes as [0]
I have also tried making a singleton but that didn't work out.
To pass data between tabs on UITabBarController /tabBar, what needs to be done is to have an intermediate. (This is usually the main UITabBarController)
Pic of UITabBarController and the child tabbar
Create a Class and link it to this TabBarController within IB
class BaseTBController: UITabBarController {
// Provide the variable which we want to pass
var workoutTitle: String = "Select a Workout"
override func viewDidLoad() {
super.viewDidLoad()
}
}
Assuming you want to pass data from TabBar2 to TabBar1, then on TabBar2 (in this case, I have it as a UITableView). In the delegate method:
extension VCLibrary: UITableViewDelegate{
// method to run when table view cell is tapped
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
// prepare to store the data to be passed to another TabBar
let tabbar = tabBarController as! BaseTBController
tabbar.workoutTitle = jsonErgWorkouts[indexPath.row].title
// Automatically select Tab1 after choosing
self.tabBarController?.selectedIndex = 0
// Deselect the selected row once we move to Tab1
tableView.deselectRow(at: indexPath, animated: true)
}
}
After selecting the data to be passed, the code (above) will automatically switch to Tab1. Within Tab1, the following code is aimed to receive the passed data
override func viewDidAppear(_ animated: Bool) {
// Obtain Passed in values from BaseTBController
let tabbar = tabBarController as! BaseTBController
// populate the Title as passed from Tab2
workoutTitleLabel.text = tabbar.workoutTitle
}
I learned this from:
https://www.youtube.com/watch?v=GL8-eM93EvQ
I have a UITableView that is populating locations and a Search Bar set as the header of that UITableView.
Whenever certain characters are entered, or a certain amount of characters are entered, the app crashes, giving me no error code.
Sometimes the app crashes after inputting one character, maybe 2 characters, maybe 3, or maybe 4. There seems to be no apparent reason behind the crashing.
The search function properly searches and populates the filtered results, but for no apparent reason, crashes if a seemingly arbitrary amount of characters are inputted.
I have tried using the exception breakpoint tool already, and it is providing me with no new information. I think it has something to do with if there are no search results.
override func viewDidLoad() {
super.viewDidLoad()
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
searchController.searchBar.placeholder = "Search Locations..."
navigationItem.hidesSearchBarWhenScrolling = false
searchController.hidesNavigationBarDuringPresentation = false
locationTableView.tableHeaderView = searchController.searchBar
searchController.searchBar.sizeToFit()
searchController.searchBar.showsCancelButton = false
searchController.searchBar.barTintColor = UIColor.white
filteredData = locationList
// Sets this view controller as presenting view controller for the search interface
definesPresentationContext = true
locationList = createArray()
// Reload the table
let range = NSMakeRange(0, self.locationTableView.numberOfSections)
let sections = NSIndexSet(indexesIn: range)
self.locationTableView.reloadSections(sections as IndexSet, with: .fade)
}
func updateSearchResults(for searchController: UISearchController) {
filterContentForSearchText(searchController.searchBar.text!)
}
func searchBarIsEmpty() -> Bool {
// Returns true if the text is empty or nil
return searchController.searchBar.text?.isEmpty ?? true
}
func filterContentForSearchText(_ searchText: String) {
filteredData = locationList.filter({( locationName : Location) -> Bool in
return locationName.locationName.lowercased().contains(searchText.lowercased())
})
let range = NSMakeRange(0, self.locationTableView.numberOfSections)
let sections = NSIndexSet(indexesIn: range)
self.locationTableView.reloadSections(sections as IndexSet, with: .fade)
}
func isFiltering() -> Bool {
return searchController.isActive && !searchBarIsEmpty()
}
func locationTableView(_ locationTableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if isFiltering() {
return filteredData.count
}
return locationList.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let locationCell = locationTableView.dequeueReusableCell(withIdentifier: "locationCell", for: indexPath) as! locationCell
let location: Location
if isFiltering() {
location = filteredData[indexPath.row]
} else {
location = locationList[indexPath.row]
}
locationCell.setLocation(location: location)
return locationCell
}
The expected result is that the UITableView should populate with filtered results. Instead, it populates them and crashes if too many characters are inputted (usually 1-4 characters).
EDIT 1: I have found through debugging the error:
Thread 1: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
appears on Line 2 on this block of code:
if isFiltering() {
location = filteredData[indexPath.row]
} else {
location = locationList[indexPath.row]
}
EDIT 2: This is the tutorial I used.
https://www.raywenderlich.com/472-uisearchcontroller-tutorial-getting-started
Seems like you are expecting the tableView to provide YOU with the number of sections... it is supposed to be driven by your own datasource.
Since you are not providing a numberOfSections in your data source I'm assuming it is 1. If all of your rows are in 1 section, all of the nifty reloading you are doing could be greatly simplified.
I suggest you read up on UITableView dataSource protocol at https://developer.apple.com/documentation/uikit/uitableviewdatasource
Reviewing the tutorial you are reading, it seems it is using a reloadData() which forces the tableView to ignore previous number of rows and reload its content with a new number of rows. And based on your findings so far, I would assume that is part of the root cause, with the tableview wrongly assuming a pre-determined number of rows and attempting to retrieve cells that are no longer within range.
I've already searched this before asking the question but I didn't find what I need.
I'm building this app where the user puts a task (not going to the app store, just for me and some friends), and the task has a category. For example: school, home, friends, etc. When the user is going to add a new task, there are 2 text fields, the description text field and the category text field. I'm using a UIPickerView so the user picks a category, then, after creating the new task, it will add the category to an array I've created called "categories".
I want to put an UISegmentedControl on top of the table view with the sections:
All - School - Home - Friends
If all is selected, it will show all the cells with no filtering. If not, it will show the cell(s) with the corresponding categories.
I've read that I need to create table view sections to each category, but this would change my code a lot, and I don't even have an idea of how to work with multiple table view sections, I've tried once but it kept repeating the cells of one section in the second.
So how can I filter the cells per category?
Can I just put for example this? :
if //code to check in which section the picker is here {
if let schoolCell = cell.categories[indexPath.row] == "School" {
schoolCell.hidden = true
}
}
Please help me!!!
EDIT:
I have this code by now:
if filterSegmentedControl.selectedSegmentIndex == 1 {
if categories[indexPath.row] == "School" {
}
}
I just don't know where to go from here. How do I recognize and hide the cells?
It seems to me that you may want to take a simpler approach first and get something working. Set up your ViewController and add a tableView and two(2) arrays for your table data. One would be for home and the other for work. Yes, I know this is simple but if you get it working, then you can build on it.
Add a variable to track which data you are displaying.
#IBOutlet var segmentedControl: UISegmentedControl!
#IBOutlet var tableView: UITableView!
// You would set this to 0, 1 or 2 for home, work and all.
var dataFilter = 0
// Data for work tasks
var tableDataWork : [String] = ["Proposal", "Send mail", "Fix printer", "Send payroll", "Pay rent"]
// Data for home tasks
var tableDataHome : [String] = ["Car payment", "Mow lawn", "Carpet clean"]
Add these functions for the segmented control.
#IBAction func segmentedControlAction(sender: AnyObject) {
switch segmentedControl.selectedSegmentIndex {
case 0:
print("Home")
dataFilter = 0
case 1:
print("Work")
dataFilter = 1
case 2:
print("All")
dataFilter = 2
default:
print("All")
dataFilter = 2
}
reload()
}
func reload() {
dispatch_async( dispatch_get_main_queue()) {
self.tableView.reloadData()
}
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("task-cell")
var title: String?
switch dataFilter {
case 0:
title = tableDataHome[indexPath.row]
case 1:
title = tableDataWork[indexPath.row]
case 2:
if indexPath.row < tableDataWork.count {
title = tableDataWork[indexPath.row]
} else {
title = tableDataHome[indexPath.row - tableDataWork.count]
}
default:
if indexPath.row < tableDataWork.count {
title = tableDataWork[indexPath.row]
} else {
title = tableDataHome[indexPath.row + tableDataWork.count]
}
}
cell?.textLabel?.text = title
if cell != nil {
return cell!
}
return UITableViewCell()
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// If
switch dataFilter {
case 0: return tableDataHome.count
case 1: return tableDataWork.count
default: return tableDataHome.count + tableDataWork.count
}
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1;
}
You can find the entire project here: https://github.com/ryantxr/segmented-control-app
It depends on your tableview.
If you use NSFetchedResultsController then you need to modify your fetch request. If you use an array directly, just use the filter function in Swift, passing in the condition, e.g. filteredArray = array.filter{$0.isAudioFile} Then, after setting your datasource array to the filtered one, call reloadData on your tableview.
You will need to keep a reference to the full array, and use the filtered one as your datasource in cellForRow...
I am trying to make an add friends list where the user selects multiple table view cells and a custom check appears for each selection. I originally used didSelectRowAtIndexPath, but this did not give me the results I am looking for since you can highlight multiple cells, but unless you unhighlight the original selected row you cannot select anymore. I then tried using didHighlighRowAtIndexPath, but this doesn't seem to work because now I am getting a nil value for my indexPath. Here is my code:
override func tableView(tableView: UITableView, didHighlightRowAtIndexPath indexPath: NSIndexPath) {
let indexPath = tableView.indexPathForSelectedRow
let currentCell = tableView.cellForRowAtIndexPath(indexPath!) as! AddedYouCell
let currentUser = PFUser.currentUser()?.username
let username = currentCell.Username.text
print(currentCell.Username.text)
let Friends = PFObject(className: "Friends");
Friends.setObject(username!, forKey: "To");
Friends.setObject(currentUser!, forKey: "From");
Friends.saveInBackgroundWithBlock { (success: Bool,error: NSError?) -> Void in
print("Friend has been added.");
currentCell.Added.image = UIImage(named: "checked.png")
}
}
How can I solve this? Thanks
I'm not going to write the code for you, but this should help you on your way:
To achieve your goal, you should separate the data from your views (cells).
Use an Array (i.e. friendList) to store your friend list and selected state of each of them, and use that Array to populate your tableView.
numberOfCellsForRow equals friendList.count
In didSelectRowAtIndexPath, use indexPath.row to change the state of your view (cell) and set the state for the same index in your Array
In cellForRowAtIndexpath, use indexPath.row to retrieve from the Array what the initial state of the cell should be.