Text and caret in VID or R3-Gui

Question

A simple example:

If I type #"w" in style "area" how do I get an #"z"? (ex. "qwerty ww" -> "qzerty zz")

Answer 1

As you want the conversion on the fly, you can either modify R3-GUI before loading. So load r3-gui.r3 down to your local directory. Then you add the line if key == #"w" [key: #"z"] to the function do-text-key, so it looks like

do-text-key: funct [
  "Process text face keyboard events."
  face [object!]
  event [event! object!]
  key
] [
  text-key-map/face: face
  text-key-map/shift?: find event/flags 'shift
  if no-edit: not tag-face? face 'edit [
    key: any [select/skip text-key-map/no-edit key 2 key]
  ]
  either char? key [
    if key == #"w" [key: #"z"]
    text-key-map/key: key
    switch/default key bind text-key-map/chars 'event [
      unless no-edit [
          insert-text-face face key
      ]
    ]
  ] [
    if find event/flags 'control [
      key: any [select text-key-map/control key key]
    ]
      text-key-map/key: key
      switch/default key text-key-map/words [return event]
  ]
  none
]

Probably the official way would be to use on-key wih Rebol3

load-gui
view [
  a: area  on-key [ ; arg: event
     if arg/type = 'key [
        if  arg/key == #"w" [arg/key:  #"z"]
     ]
     do-actor/style face 'on-key arg face/style
  ]
]

And finally a way to do this with Rebol2 on the fly

key-event: func [face event] [
    if event/type = 'key [ 
        if all [event/key = #"w"   ] [
            append a/text  #"z" 
            focus a
            view w 
           return false
        ]
    ] 
    event 
] 
insert-event-func :key-event        

view w: layout [
    a: area 
]