display firebase data inside uipickerview

You have to implement it in

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
            if labelTxt.isFirstResponder {
                return items[row] as String
            }
            return nil
        }

I don't understand what you expect with

if labelTxt.isFirstResponder

Add a test to check:

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
            if labelTxt.isFirstResponder {
               print("row", row, items[row])
                return items[row] as String
            }
           print("row", row, nil)
            return nil
        }

But the error is probably in viewDidLoad:

    override func viewDidLoad() { 
        super.viewDidLoad() 
        
        let pickerView = UIPickerView() 
        infoPickerViewer.delegate = self 
        infoPickerViewer.dataSource = self 
        
        dbRef = Firestore.firestore().collection(ITEMS_REF) 
        
        labelTxt.inputView = pickerView 
        labelTxt.delegate = self 
 
        getItems() 
    }

Line 10, you set the inputView to a picker created locally that is never initialized.

I would change with this:

    override func viewDidLoad() {
        super.viewDidLoad()
       
        // REMOVE THIS.        let pickerView = UIPickerView()
        infoPickerViewer.delegate = self
        infoPickerViewer.dataSource = self
       
        dbRef = Firestore.firestore().collection(ITEMS_REF)
       
        labelTxt.inputView = infoPickerViewer  // REPLACING pickerView
        labelTxt.delegate = self

        getItems()
    }

Hi Claude,

i use labelTxt.isFirstResponder so when i click on the text field, the pickerviewer shows up and when i select something from the pickviewer, it shows in the text field. I'm using that on a separate project with the difference that I'm using a local array.

Currently I'm not getting an error, the issue that i'm having is how to display the Firebase info in the pickerviewer. Here is a print out of the console:

ITEMS_CODE item1

ITEMS_NAME item2

ITEMS_CODE item5

ITEMS_NAME item6

ITEMS_CODE item3

ITEMS_NAME item4

The only item i want to display in the pickerviewer is the ITEM_NAME, i'm going to use the ITEM_CODE to run a query to Firebase on a different VC.

I made a change to the getItems() function:

    func getItems() {
        dbRef.getDocuments { (snapshot, error) in
            if let err = error {
                debugPrint("error fetching docs: \(err)")
            } else {
                
                let snap = snapshot
                for document in snap!.documents {
                    let data = document.data()
                    let itemCode = data[ITEMS_CODE] as? String ?? ""
                    let itemName = data[ITEMS_NAME] as? String ?? ""
                    
                    let t = intemInfo(itemCode: itemCode, itemName: itemName)
                    
                    self.itemsClass.append(t)
                    
                    //print(document.data())
                    print("ITEMS_CODE", itemCode as Any)
                    print("ITEMS_NAME", itemName as Any)
                    
                }
            }
        }
    }

My confusion is on how to display just the itemName. Hope this is clear.

I miss something.

in pickerView titleForRow, you use items[row] as data source.

But I do not see where you set items in getItems. Maybe in intemInfo (probably itemInfo mispelled), but you do not show the func.

something like:

                items = []
                for document in snap!.documents {
                    let data = document.data()
                    let itemCode = data[ITEMS_CODE] as? String ?? ""
                    let itemName = data[ITEMS_NAME] as? String ?? ""
                    items.append(itemName)     // Unless done in intemInfo ?
                    let t = intemInfo(itemCode: itemCode, itemName: itemName)
                  
                    self.itemsClass.append(t)
                  
                    //print(document.data())
                    print("ITEMS_CODE", itemCode as Any)
                    print("ITEMS_NAME", itemName as Any)
                  
                }

Sorry, intemInfo it's a typo. I'm using the following var:

var itemsClass = [itemInfo]()

This is the class:

class itemInfo {

    private(set) var itemCode: String?
    private(set) var itemName: String?
   
    init(itemCode: String, itemName: String) {

        self.itemCode = itemCode
        self.itemName = itemName
    }
}

and this is how the pickerviewer is configured:

func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 1
    }

    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        if labelTxt.isFirstResponder {
            return self.itemsClass.count
        }
        return 0
    }

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
            if labelTxt.isFirstResponder {
                return itemsClass[row] //here im getting the following error: Cannot convert return      
                                                          //expression of type 'itemInfo' to return type 'String?'
            }
            return nil
        }

This:

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String?

yes, needs to return a string.

I have updated the name of the class (Thank you). Code has been corrected, added few things i was missing and is working as expected.

Thank you for your help.

I updated my original code with all the changes.