How to return selected value in UIPickerDelegate when created programatically

Question

I have a viewController that has a bunch of inputs on it. Some of them are normal text but some require input from a picker. I decided to move the implementation of each PickerDelegate and PickerDataSource into a separate file to keep things a little cleaner. The data is appearing but on select of the Picker I don't know how to get the event to fire in my viewController. Currently it only fires in the PickerDelete class.

Some basic layout information is

class MyClass: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

let jobTypePickerValues = ["value1", "value2"]

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

// returns the # of rows in each component..
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return jobTypePickerValues.count
}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    return jobTypePickerValues[row]
}

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int)
{
    //println("I want this in the view controller that set up the picker")
}

In my view controller which is showing the picker I have the following

    override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.


    myClassSource = MyClass()
    pickerView = UIPickerView()
    pickerView.dataSource = myClassSource
    pickerView.delegate = myClassSource

    // set the input view of the job type to be a picker view
    textInput.inputView = pickerView
    textInput.text = jobTypePickerValues[0]
}

you can make your MyClass custom delegate which can be called in your view controller class.. this will solve the problem — Divyanshu Sharma, Sep 08 '16 at 12:42

Nirav D · Accepted Answer · 2016-09-12T13:53:25.540

0

You need to create one custom delegate and implement in the ViewController where you are creating pickerView.

protocol CustomPickerDelegate {
     func selectedItem(item: String)
}

Now create instance of this protocol inside MyClass and implement inside the `ViewController``

class MyClass: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

    let jobTypePickerValues = ["value1", "value2"]
    var delegate: CustomPickerDelegate?
    .. Other code and methods

    func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
         delegate?. selectedItem(jobTypePickerValues[row])
    }
}

Now set the delegate in viewDidLoad and implement the method of protocol.

class ViewController: UIViewController, CustomPickerDelegate {

     override func viewDidLoad() {
         super.viewDidLoad()

         myClassSource = MyClass()
         myClassSource.delegate = self
         pickerView = UIPickerView()
         pickerView.dataSource = myClassSource
         pickerView.delegate = myClassSource

         // set the input view of the job type to be a picker view
         textInput.inputView = pickerView
         textInput.text = jobTypePickerValues[0]
     }

      func selectedItem(item: String) {

          textInput.text = item
      }
}

edited Sep 12 '16 at 13:53

answered Sep 08 '16 at 12:51

Nirav D

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Thanks this answered my question but I think I need to add that in the MyClass class I had to add the listener for the change event and then call the delegate method which looked like this 'func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) { delegate?. selectedItem("this is being sent to the ViewController") }' – Matt Sep 12 '16 at 10:18
@Matt Yes i forgot to add that code `delegate?. selectedItem("this is being sent to the ViewController")` – Nirav D Sep 12 '16 at 10:21
But other then there is no issue. – Nirav D Sep 12 '16 at 10:22
Welcome matt, Happy Coding :) – Nirav D Sep 12 '16 at 10:23
Will you please up vote also so it helps to others too :) – Nirav D Sep 12 '16 at 10:23

How to return selected value in UIPickerDelegate when created programatically

1 Answers1