Move all views up after hiding one - swift

Question

In my Android app, I was able to create use a standard table with rows and have text boxes in it. Based on user preferences, some of these rows are shown/hidden. For example if the user doesn't want to enter in cash/credit sales, or track any discounts given to a customer, etc, these fields shouldn't appear.
I simply would hide the entire row, and just like a DIV in html, the rest of the rows would move up nicely.
So for example:
element1
element2
element3
I'd want to remove element 2, and 3 moves up and takes 2's place. I'll probably have 8 of these fields btw.
In iOS, however, is something like this possible? Some googling yielded results that more or less made this seem very complicated for showing/hiding form elements and having everything slide up nicely. Some solutions included setting up very complex autolayout scenarios dynamically, or not using autolayout at all, etc. Then again, these solutions were for older versions of ios.
Is something like this possible? How could I achieve this?
Thanks!

Answer 1

Use UITableView.
UITableView allows you to represent list of cells and manipulate them (add, remove, reorder) with animations.
In you case every option will be a UITableViewCell.
Create a subclass of UITableViewController
Set a dataSource of UITableView
Implement UITableViewDataSource
That is 2 functions
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath:NSIndexPath) -> UITableViewCell
Update TableView items
You can easily reload tableView by editing your objects and calling reloadData method on tableView
// Add, remove or replace your objects you want to display in table View
objects = ["1", "2", "3"]
// call tableView to reload it's data. TableView will call dataSource delegates methods and update itself
tableView.reloadData()
You can remove or add specific item in tableView
First update your object, by removing or adding it, than call update tableView and say what cell (at which position) it should add or remove. You can also say what type of animation it should use
var index = 2
// Update your object Model, here we remove 1 item at index 2
objects.removeAtIndex(index)
// saying tableView to remove 1 cell with Fade animation.
tableView.deleteRowsAtIndexPaths([NSIndexPath(forRow: index, inSection: 0)], withRowAnimation: .Fade)
Here is full Code example
class MasterViewController: UITableViewController {
var objects = ["Option 1", "Option 2", "Option 3"]
func insert(obj: String, at: Int) {
objects.append(obj)
let indexPath = NSIndexPath(forRow: at, inSection: 0)
self.tableView.insertRowsAtIndexPaths([indexPath], withRowAnimation: .Automatic)
}
func deleteAt(index: Int) {
objects.removeAtIndex(index)
tableView.deleteRowsAtIndexPaths([NSIndexPath(forRow: index, inSection: 0)], withRowAnimation: .Fade)
}
override func viewDidLoad() {
super.viewDidLoad()
}
func insertNewObject(sender: AnyObject) {
insert(NSDate.date().description, at: 0)
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return objects.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell
let object = objects[indexPath.row]
cell.textLabel?.text = object
return cell
}
override func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
// Return false if you do not want the specified item to be editable.
return true
}
override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
if editingStyle == .Delete {
deleteAt(indexPath.row)
} else if editingStyle == .Insert {
// Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view.
}
}