Vertically aligning text in an NSTextField using Swift - swift

Question

I have been reading through the various options on how to set the vertical alignment on an NSTextField. I want the text to be displayed in the center and to do it programatically in Swift. Here are the things I have looked so far:
http://www.cocoabuilder.com/archive/cocoa/174994-repositioning-an-nstextfieldcell.html
https://red-sweater.com/blog/148/what-a-difference-a-cell-makes
Vertically Centre Text in NSSecureTextField with subclassing
Get NSTextField contents to scale
vertically align text in a CATextLayer?
One thing I have tried in Swift is to set the following property:
textField.usesSingleLineMode = true
Any tips on the best way to vertically center text would be much appreciated!

Answer 1

This is very hard to do, as Apple makes this very difficult. I achieved it by subclassing NSTextFieldCell and overriding the drawingRectForBounds: method like so:
override func drawingRectForBounds(theRect: NSRect) -> NSRect {
let newRect = NSRect(x: 0, y: (theRect.size.height - 22) / 2, width: theRect.size.width, height: 22)
return super.drawingRectForBounds(newRect)
}
This is just my way to do it, I'm sure there are better ways, which I don't know (yet). And this only works for the standard font size in TextFields (which gives a text height of 22). That's why I hardcoded that. Haven't figured out yet, how to get the height in the cell if you change the font.
Result:

Answer 2

Try this on a playground, it centers the text perfectly, use it on your projects! Hope it helps!
import Cocoa
let cell = NSTableCellView()
cell.frame = NSRect(x: 0, y: 0, width: 100, height: 100)
let tf = NSTextField()
tf.frame = cell.frame
tf.stringValue = "MyTextfield"
tf.alignment = .Center
let stringHeight: CGFloat = tf.attributedStringValue.size().height
let frame = tf.frame
var titleRect: NSRect = tf.cell!.titleRectForBounds(frame)
titleRect.size.height = stringHeight + ( stringHeight - (tf.font!.ascender + tf.font!.descender ) )
titleRect.origin.y = frame.size.height / 2 - tf.lastBaselineOffsetFromBottom - tf.font!.xHeight / 2
tf.frame = titleRect
cell.addSubview(tf)

Answer 3

I have added the NSTextField inside a NSView and centered it.
Another solution was (in an iOS project) to create a UILabel and allow it adjust its size (sizeToFit()) and again embed it inside a UIView.
I personally don't like the calculations in previous answers and the second solution for iOS works for all texts size and row numbers.

Answer 4

I was also facing vertical alignment issue with NSTextField. My requirement involved, rendering a single-line string inside a NSTextField. Additionally,
textfield needed to be resize implying we had programatically resized the font-point-size of the text inside text-field on resize. In this scenario we faced vertical-alignment issues - the mis-alignment was tough to grasp/understand in a straight forward way.
What finally worked:
So, in my scenario a simple,
turn off the "Single Line Mode" in interface builder
for the text-field solved the issue.

Answer 5

The accepted answer works perfectly and here's the Swift3 version.
class VerticallyAlignedTextFieldCell: NSTextFieldCell {
override func drawingRect(forBounds rect: NSRect) -> NSRect {
let newRect = NSRect(x: 0, y: (rect.size.height - 22) / 2, width: rect.size.width, height: 22)
return super.drawingRect(forBounds: newRect)
}
}