Two UIPickerViews and different combinations lead

问题:

I am very new to swift Xcode and would like some help on UIPickerView.

I am trying to create two UIPickerViews, one called "From" and one called "To". "From" contains A, B and "To" contains B, C

Basically, if "From" is A and "To" is B then a Photo of car will appear on the same viewController. if "From" is B and "To" is B then a photo of strawberry will appear and so on.

Can anyone give me any hints on how to do this? I've only managed to create the first UIPickerView.

import UIKit

class ViewController: UIViewController,UIPickerViewDelegate, UIPickerViewDataSource {

    @IBOutlet var Picker1:UIPickerView!

    var Array = ["A","B","C"]

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

        Picker1.delegate = self
        Picker1.dataSource = self
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

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

    func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return Array.count
    }

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

回答1:

var savedVal1 = "" as String
var savedVal2 = "" as String
var array1 = NSArray()
var array2 = NSArray()

override func viewDidLoad() {
    super.viewDidLoad()

    Picker1.delegate = self
    Picker1.dataSource = self
    Picker1.tag = 1

    Picker2.delegate = self
    Picker2.dataSource = self
    Picker2.tag = 2
}


func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    if pickerView.tag == 1 {
        return array1[row]
    }
    else{
       return array2[row]
    }
}


func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    if pickerView.tag == 1 {
       return array1.count
    }
    else{
       return array2.count
    }
}

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int{

    return 1
}

func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, inComponent component: Int){
        if pickerView.tag == 1 {
            savedVal1 = array1[row]
            // compare 2 values here & then take steps which fulfill your criteria.

        }
        else{
            savedVal2 = array2[row]
            //compare 2 values here & then take steps which fulfill your criteria.
        }
    }

Hope it helps.

回答2:

Where is your PickerView2?

@IBOutlet var Picker2:UIPickerView!

In viewdidload load as you done

Picker1.delegate = self
Picker1.dataSource = self

If you are using same data source or different please check the picker view in UIPickerViewDelegate, UIPickerViewDataSource method like

 If (Picker1) {

} else if (Picker2) {

}