How to dynamically update autohotkey GUI elements - autohotkey

Question

I've created a GUI using AHK. I am storing the Id and description as key-value pairs. I want to update the Desc when the user enters the ID with the corresponding desc stored in the associative array. How can I dynamically updated the GUI?
^h::
oKeys := []
oValues := []
oArray := {}
if (WinExist("ahk_id " hwndgui)) {
Gui, Destroy
return
}
gui, add, text,, Type:
Gui, Add, DropDownList,vType, TSO|PAX|DVI
gui, add, text,, ID:
Gui, Add, Edit, vId
gui, add, text,, Partial|Complete:
Gui, Add, DropDownList,vPartial, Partial||Complete
gui, add, text,, Left-Behind:
Gui, Add, DropDownList,vLeft, False||True
gui, add, text,, XFR-Type:
Gui, Add, DropDownList,vXFR, Standard||Contact|Theft
gui, add, text,, DESC:
Gui, Add, Edit, vDesc , oArray[(TypeId)]
Gui, Add, Button, Default gOK, OK
Gui, Show, Hide
Gui, +LastFound
hwndgui:=WinExist()
OK:
Gui, Submit
oKeys.Push((TypeId))
oValues.Push((Desc))
Loop, % oKeys.Length()
oArray[oKeys[A_Index]] := oValues[A_Index]
if WinExist("labelImg")
WinActivate ; Uses the last found window.
Send, ^a
Send, %Type%_%Id%_%Partial%_%Desc%
for vKey, vValue in oArray
vOutput .= vKey " " vValue "`r`n"
MsgBox, % vOutput
Gui, Show
return