Programmatically Create and Show UIPickerView

Question

I am attempting to create a UIPickerView programmatically and display it as the firstResponder of a textfield, however, the picker view is not showing up. textField is connected to an object in the interface builder, but pickerView is being created programatically.

class View: UIViewController {
    @IBOutlet var picker : UIPickerView = UIPickerView.alloc()
    @IBOutlet var textField : UITextField = nil
    override func viewDidLoad() {
        super.viewDidLoad()
        picker = UIPickerView()
        picker.delegate = self
        picker.dataSource = self
        picker.backgroundColor = UIColor.blackColor()
        textField.inputView = picker
    }
}
extension View: UIPickerViewDataSource {

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

    func pickerView(pickerView: UIPickerView!, numberOfRowsInComponent component: Int) -> Int {
        return 5
    }
}

extension View: UIPickerViewDelegate {

    func pickerView(pickerView: UIPickerView!, titleForRow row: Int, forComponent component: Int) -> String!
    {
        return "Text"
    }
}

Why can't I see this pickerView when I run the app?

Edit: Adding a breakpoint inside the extensions does not stop the program, they are not being called.

In your viewDidLoad, change var picker : UIPickerView = ... to picker = .... You are creating a local (and temporary) picker. — rmaddy
– rmaddy, Commented Jul 19, 2014 at 3:17
I am now getting three errors on that line: Consecutive statements on a line must be separated by ';', Expected expression, and Expression resolves to an unused l-value — trumpeter201
– trumpeter201, Commented Jul 19, 2014 at 3:23
And if I remove that line, I get a fatal error at runtime: Can't unwrap optional.none — trumpeter201
– trumpeter201, Commented Jul 19, 2014 at 3:24
UIPickerView.alloc() is deprecated now, simply use UIPickerView() instead — kat
– kat, Commented Mar 17, 2017 at 19:05
Both can be created programmatically. Here is a well documented example in Objective C. — jungledev
– jungledev, Commented Sep 5, 2017 at 5:01

trumpeter201 · Accepted Answer · 2014-07-19 04:25:31Z

5

I found the problem-the code for assigning the input view doesn't include self. It should read

self.textField.inputView = picker

answered Jul 19, 2014 at 4:25

trumpeter201

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Comments

Jason Wiles · Accepted Answer · 2014-07-27 19:56:21Z

2

I was having the same problem trying to get the picker view to show up when clicking in the textfield. My issue was that for some reason my iOS simulator had the "Connect Hardware Keyboard" checked. In the iOS menu go to Hardware -> Keyboard and make sure "Connect Hardware Keyboard" is unchecked. Feels dumb now not noticing any keyboard was popping up in the app for several hours but hopefully this will help save someone else the frustration.

Just wanted to add an edit: In the iOS simulator you can try toggling the software keyboard (command+K) This worked for me as well in this case and allowed me to keep the hardware keyboard connected. Just something to check quickly before assuming your code is incorrect.

edited Jul 27, 2014 at 19:56

answered Jul 24, 2014 at 19:15

Jason Wiles

313 bronze badges

1 Comment

Hugo Over a year ago

Thanks, solved my problem! As yourself I spent some time figuring out why it didn't work...

Community · Accepted Answer · 2020-06-20 09:12:55Z

2

I'm not sure why you cannot see the picker. But it's a wrong way.

To create an instance using:

 picker = UIPickerView.alloc()

In Swift:

you should use:

picker = UIPickerView()

edited Jun 20, 2020 at 9:12

CommunityBot

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answered Jul 19, 2014 at 3:58

Louis Zhu

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1 Comment

trumpeter201 Over a year ago

I made that change, thanks, but the picker still doesn't seem to exist, the optional.none error still persists.

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