swift update textview after typing new text - swift

Question

I'm making an app in swift 3
I have a TableViewController, when I click on a row it opens a ViewController in which there is a TextView. When I click on it, I am able to edit it, but the changes are not "saved". when I go back to my list and re-click on the same row, the text is back to "Default", I've been on this problem all day, and I don't know how to solve it, I've tried solution from stackoverflow but only give solution to change the text colours.
So how can I do that ?

Answer 1

Based on what you've said so far, I can only assume that you are not storing the new text that's been entered into your UITextView.
The reason that the changes are not being saved is that every time you "open" a new ViewController by tapping on a TableViewCell, it is a brand new instance of that ViewController. That means that it has no input as far as what should be displayed in the TextView, and therefore displays the default text.
But how do I fix it?
This is going to require that you save your TextView's text every time that you leave or dismiss the ViewController. This is because when you leave the ViewController, it is being released from memory. This means that anything that was written there no longer exists. I would suggest storing the text in an array of strings on your TableViewController, which should allow for the text to persist over the life cycle of the app.
The text disappears when I close the app!
This is something that will require data persistence, and for that I would suggest reading up on how to use Core Data to store and persist data across multiple app life cycles.

Answer 2

There are many ways to achieve that, the idea is to set the text of the text view in its view controller's initialization.
So, you need a place to save the data entered by the user, and then read that data again in the view controller's initialization.
One way to do that is using a singleton class to save the data, like this for example:
class SharedData {
static let instance = SharedData()
var textEnteredByUser: String?
}
Now, when the user enters text, save that text in the string we have in 'SharedData' like this:
SharedData.instance.textEnteredByUser = textView.text!
Now, we have the data entered by the user saved, we need to set the data in the text view before it appears in the screen, and this can be achieved inside viewDidLoad method of your view controller like this:
override func viewDidLoad() {
super.viewDidLoad()
textView.text = SharedData.instance.textEnteredByUser
}
You can also save your data in user defaults instead of the singleton class like this:
UserDefaults.standard.set(textView.text!, forKey: "textEnteredByUser")
And then retrieve the saved text this way:
UserDefaults.standard.string(forKey: "textEnteredByUser")
Note: The singleton solution keeps the data shared between different view controllers, but does not persist data after closing the application, and this is what user default does.