Find UILabel in UIView in Swift

Question

I'm trying to find my UILabels in my superview of my UIViewControllers. This is my code:

func watch(startTime:String, endTime:String) {
    if superview == nil {println("NightWatcher: No viewcontroller specified");return}

    listSubviewsOfView(self.superview!)

}

func listSubviewsOfView(view: UIView) {
    var subviews = view.subviews

    if (subviews.count == 0) { return }

    view.backgroundColor = UIColor.blackColor()

    for subview in subviews {
        if subview.isKindOfClass(UILabel) {
            // do something with label..
        }
        self.listSubviewsOfView(subview as UIView)
    }
}

This is how it is recommended to in Objective-C, but in Swift I get nothing but UIViews and CALayer. I definitely have UILabels in the view that is supplied to this method. What am I missing?

The call in my UIViewController:

  NightWatcher(view: self.view).watch("21:00", endTime: "08:30") // still working on

I tested this with Xcode 6b6 and it works: I am able to find a UILabel inside a UIView that is a subview of my viewController's view. Do you use Xcode 6b6? Do you use a Storyboard? When/how do you call this method? — Imanou Petit, Aug 21 '14 at 00:37
Thanks for your reply. I use Xcode6b5, Storyboard. The method is placed in a seperate non-UI class and I call it from my UIViewController. — Casper, Aug 21 '14 at 07:42
In `watch:`, what do you get when you call `listSubviewsOfView(view)` instead of `listSubviewsOfView(self.superview!)`? — Imanou Petit, Aug 21 '14 at 08:00
I have a variable in my class called: var superview:UIView?. I cannot call it as 'view'. The superview is thus the 'self.view' — Casper, Aug 21 '14 at 08:02

score 11 · Answer 1 · edited Jan 25 '17 at 22:12

11

Here's a version that will return an Array of all the UILabel views in whatever view you pass in:

func getLabelsInView(view: UIView) -> [UILabel] {
    var results = [UILabel]()
    for subview in view.subviews as [UIView] {
        if let labelView = subview as? UILabel {
            results += [labelView]
        } else {
            results += getLabelsInView(view: subview)
        }
    }
    return results
}

Then you can iterate over them to do whatever you'd like:

override func viewDidLoad() {
    super.viewDidLoad()

    let labels = getLabelsInView(self.view)
    for label in labels {
        println(label.text)
    }
}

edited Jan 25 '17 at 22:12

Fattie

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answered Aug 20 '14 at 19:59

Nate Cook

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This works just fine.. Thanks! I'll try to figure out what's wrong – Casper Aug 21 '14 at 07:52
1

I'm running this in Swift 3.1 but it returns two objects, one of which is the label of a UIButton, not a UILabel in itself. Is there a way to make it more explicit? – Alexandros Apr 17 '17 at 07:11
@Alexandros Same here. DId you find a better solution? – Sealer_05 Jul 04 '17 at 19:33
I'm doing this: `for case let label as UILabel in view.subviews {...}` – Robo Robok Aug 06 '17 at 23:02

score 10 · Accepted Answer · edited Nov 21 '17 at 20:48

10

Using functional programming concepts you can achieve this much easier.

let labels = self.view.subviews.flatMap { $0 as? UILabel }

for label in labels {
//Do something with label
}

edited Nov 21 '17 at 20:48

Brian Parkes

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answered Sep 28 '17 at 22:50

mKane

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Updated this to be the accepted answer as it applies for all code bases using Swift 2.0+. It's much cleaner and (arguable) more readable. Swift has come a long way :) – Casper Sep 29 '17 at 09:28
I get `Value of type 'UIView' has no member 'flatMap'` – Gal Oct 03 '17 at 08:45
@Gal If you are writing that code in the correct context it should work. Comment this code out and cmd+B. Do you see any errors? If not uncomment and cmd+B again – mKane Oct 04 '17 at 16:53

score 1 · Answer 3 · answered Nov 12 '18 at 21:50

1

Swift 4

Adepting mKane's answer you can use this code:

let labels = self.view.subviews.compactMap { $0 as? UILabel }

for label in labels {
   // do whatever
}

answered Nov 12 '18 at 21:50

Patrick J.

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7

Marwen Doukh · Answer 4 · 2018-11-30T10:27:11.497

1

You could set a tag to your UILabel in the Storyboard or programmatically using:

myLabel.tag = 1234

Then, to find it use:

let myLabel = view.viewWithTag(1234)

edited Nov 30 '18 at 10:27

answered Nov 30 '18 at 09:35

Marwen Doukh

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17
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Find UILabel in UIView in Swift

4 Answers4

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