Swift 4 - NSTextField Selected?

Question

On a OSX app I have 3 NSTextField and 2 NSButtons

@IBOutlet weak var TF1: NSTextField!
@IBOutlet weak var TF2: NSTextField!
@IBOutlet weak var TF3: NSTextField!
@IBOutlet weak var Bt1: NSButton!
@IBOutlet weak var Bt2: NSButton!

Bt1 will write on the selected textfield "Button 1 Pressed"
Bt2 will write on the selected textfield "Button 2 Pressed"

But I haven't found how to detect which NSTextField is selected. Does anyone have a sample code/example on this?

Edit:

2 solutions works perfectly
Thanks to @MwcsMac and @sfjac

@IBAction func test(_ sender: NSButton) {
    var textField : NSTextField? = nil
    // the focused control is the first responder of the window
    let responder = sender.window?.firstResponder
    // if a text field is focused, the first responder is the field editor, a NSTextView
   if let textView = (responder as? NSTextView) {
        if textView.isFieldEditor {
            // the focused text field is the delegate of the field editor
            textField = textView.delegate as? NSTextField
        }
    }
    else {
        if responder is NSTextField {
            textField = responder as? NSTextField
        }
    }
    textField?.stringValue = "test"
}

and

    @IBAction func Bt1Pressed(_ sender: NSButton) {
    if isTextField(inFocus: TF1){
        TF1.stringValue = "B1 Pressed"
    }
    if isTextField(inFocus: TF2){
        TF2.stringValue = "B1 Pressed"
    }
    if isTextField(inFocus: TF3){
        TF3.stringValue = "B1 Pressed"
    }
}

@IBAction func Bt2Pressed(_ sender: NSButton) {
    if isTextField(inFocus: TF1) {
        TF1.stringValue = "B2 Pressed"
    }
    if isTextField(inFocus: TF2){
        TF2.stringValue = "B2 Pressed"
    }
    if isTextField(inFocus: TF3){
        TF3.stringValue = "B2 Pressed"
    }
}

func isTextField(inFocus textField: NSTextField) -> Bool {
    var inFocus = false
    inFocus = (textField.window?.firstResponder is NSTextView) && textField.window?.fieldEditor(false, for: nil) != nil && textField.isEqual(to: (textField.window?.firstResponder as? NSTextView)?.delegate)
    return inFocus
}

Possible duplicate of [How to detect when NSTextField has the focus or is it's content selected cocoa](https://stackoverflow.com/questions/25692122/how-to-detect-when-nstextfield-has-the-focus-or-is-its-content-selected-cocoa) — koen, Jan 29 '18 at 17:58
@Koen i know but i'm really bad in Objectives-C so i havn't understand the answer — Rombond, Jan 29 '18 at 18:59
You don't have to translate Objective-C to Swift. Recognize which method is called and do the same in Swift. But your question is not a duplicate, the linked question is about getting notified. Do you want to check if a text field is focused or do you want to get the focused text field? — Willeke, Jan 30 '18 at 08:47
@Willeke i want to get which textfield is focused to write in — Rombond, Jan 30 '18 at 17:20

score 2 · Accepted Answer · answered Jan 30 '18 at 21:39

This should give you the result you are looking for. This is tested on Xcode 9.2 and on macOS 10.13.3.

@IBAction func Bt1Pressed(_ sender: NSButton) {
    if isTextField(inFocus: TF1){
        TF1.stringValue = "B1 Pressed"
    }
    if isTextField(inFocus: TF2){
        TF2.stringValue = "B1 Pressed"
    }
    if isTextField(inFocus: TF3){
        TF3.stringValue = "B1 Pressed"
    }
}

@IBAction func Bt2Pressed(_ sender: NSButton) {
    if isTextField(inFocus: TF1) {
        TF1.stringValue = "B2 Pressed"
    }
    if isTextField(inFocus: TF2){
        TF2.stringValue = "B2 Pressed"
    }
    if isTextField(inFocus: TF3){
        TF3.stringValue = "B2 Pressed"
    }
}

func isTextField(inFocus textField: NSTextField) -> Bool {
    var inFocus = false
    inFocus = (textField.window?.firstResponder is NSTextView) && textField.window?.fieldEditor(false, for: nil) != nil && textField.isEqual(to: (textField.window?.firstResponder as? NSTextView)?.delegate)
    return inFocus
}

score 2 · Answer 2 · answered Jan 31 '18 at 11:00

Here's what I do in Objective-C:

id responder = [window firstResponder];
if (responder && [responder isKindOfClass:[NSTextView class]] && [responder isFieldEditor])
    responder = [responder delegate];
if ([responder isKindOfClass:[NSTextField class]])
    [responder setStringValue:@"test"];

and my (probably clumsy) translation to Swift:

@IBAction func test(_ sender: NSButton) {
    var textField : NSTextField? = nil
    // the focused control is the first responder of the window
    let responder = sender.window?.firstResponder
    // if a text field is focused, the first responder is the field editor, a NSTextView
    if let textView = (responder as? NSTextView) {
        if textView.isFieldEditor {
            // the focused text field is the delegate of the field editor
            textField = textView.delegate as? NSTextField
        }
    }
    else {
        if responder is NSTextField {
            textField = responder as? NSTextField
        }
    }
    textField?.stringValue = "test"
}

@Rombond I would suggest you accept this answer instead of mine. As it is a much cleaner answer than mine. — MwcsMac, Feb 01 '18 at 15:12

koen · Answer 3 · 2018-01-31T13:31:03.760

-1

Your textfield with the focus will be the firstResponder. You can check for that and then execute your code:

if myNSWindow.firstResponder == TF1 {
  // Do something with TF1
}

(pseudo-code, typed in browser, not tested with Xcode)

edited Jan 31 '18 at 13:31

answered Jan 30 '18 at 18:35

koen

5,383
7
50
89

I don't mind a down vote, but could you explain why, so I can try to improve my answer? – koen Jan 31 '18 at 13:30

Swift 4 - NSTextField Selected?

Edit:

3 Answers3