Add Pinch-In and Pinch-Out (Icon Zoom) back into Apple’s Finder

Ok, this has annoyed many people out there, including me: Apple found it clever to remove the pinch gesture on the icon view of the Finder window. For what ever reason, but it was annoying me enough to find a solution.

Here it is: Create a small Apple script like this:

(*
  This is a very stupid little script to allow for pinch-zoom in Finder
  which some very stupid little mind has disabled in recent versions of
  MacOS
  
  (c) 2014 Matthias Nott,
  Credits to @drdrang from
  http://www.leancrew.com/all-this/2013/10/quick-switch-to-big-finder-icons/
*)

on run argv
  -- Define your icon sizes here
  
  set u to {16, 32, 64, 128, 256, 512}
  set d to {512, 256, 128, 64, 32, 16, 0}
  
  -- Leave everyting alone from here on
  
  if (count of argv) < 0 then
    set w to item 1 of argv
  else
    set w to "down"
  end if
  
  
  tell application "Finder"
    activate
    if window 1 exists then
      
      set f to target of Finder window 1
      set s to the icon size of icon view options of Finder window 1
      
      if w = "up" then
        set t to u
      else
        set t to d
      end if
      
      set c to count of t
      
      repeat with n from 1 to c
        if ((w = "up" and s < item n of t) or (w = "down" and s > item n of t) and n < c) then
          set s to (item n of t)
          set the current view of Finder window 1 to icon view
          set icon size of icon view options of Finder window 1 to s
          set arrangement of icon view options of Finder window 1 to arranged by name
          close front Finder window
          open f
          exit repeat
        end if
      end repeat
      
    end if
  end tell
end run

Save it into a Folder like

~/Library/Scripts/Zoom.scpt

Then assign it to a pinch gesture (two finger pinch-in or out on the Finder app using BetterTouchTool) where you specify to run a Terminal Command like so:

osascript  ~/Library/Scripts/Zoom.scpt down

and

osascript  ~/Library/Scripts/Zoom.scpt up

If you want to have a finder grained control, you can add icon sizes to the two lists at the top of the script; valid values range from 0 to 512.

Credits go to @drdrang.