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swiftcocoanstextfieldappkit

Draw NSTextField setting the content NSRect

Given a struct Concept that has an associated text: String and area: NSRect, that when drawn on the view, it will draw the String in the given NSRect.

I would like to on click, show a NSTextField which "content" (cell) NSRect is equal to the given NSRect

If I tried to set up textField.frame = concept.area, the cell will be rendered in an inset position considering the border + padding of the NSTextField, so it will render the text in a different, slightly moved, NSRect.

In code the idea would be something like

struct Concept {
  let text: String
  let area: NSRect

  func draw() {
    text.draw(inRect: area)
  }
}

let conceptRect = NSRect(x: 50, y: 60, width: 80, height: 20)
let concept = Concept(text: "sample text", area: conceptRect)

let textField = NSTextField()
textField.stringValue = concept.text

textField.???? = area
let textFieldRect = textField.frame

assert(textFieldRect != conceptRect)
assert(textFieldRect.contains(conceptRect))

And the expected result should look like:

enter image description here

any ideas on how can I achieve this?

thanks

Solution

  • You don't say how you're drawing the string in the area, which can affect exactly where it draws.

    If you want to figure out what the text field's border padding is, you can compare its cell's drawingRect(forBounds:) with the text field's bounds. The drawing rect will be inset by a bit from the bounds. To compute a frame to get a particular drawing rect, you reverse that by "outsetting" from the desired drawing rect by the same amount.