I can't set the uipickerview datasource and delegate from an outside file

I can't seem to set my outside pickerview datasource and delegate to my main view. Is there away I can set it? I want to keep my pickerview in a separate file due to other future views that might use it

This is my custom picker view

final class LenghtPickerView: UIPickerView, UIPickerViewDataSource, UIPickerViewDelegate {

    let feet = Array(4...7)
    let inches = Array(1...11)

    private var textFieldBeginEdited: UITextField?

    var selectedValue: String {
        get {
            return "\(feet[selectedRow(inComponent: 0)]) ft \(inches[selectedRow(inComponent: 0)]) in"
        }
    }

    func numberOfComponents(in pickerView: UIPickerView) -> Int {
        return 2
    }

    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        if component == 0 {
            return feet.count
        } else {
            return inches.count
        }
    }

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        if component == 0 {
            return String(feet[row])
        } else {
            return String(inches[row])
        }
    }
}

and in my main view declaring it private let lenghtPickerView = LenghtPickerView() also tried private let lenghtPickerView: LenghtPickerView = LenghtPickerView()

cant set the datasource and delegate in order for the data to be render

lenghtPickerView.delegate = self
lenghtPickerView.dataSource = self