capturing keys within a field

Is there a way to capture keys within a field as they get typed along? With feel and engage, I can get keys as they are typed, at the cost of writing key handling. Is there a way to copy the field face object and modify its behavior? Can I access the string containing the characters showing on the screen? Also How to use a face created with make face inside a VID layout? R ebol[] view-block: [ txt: field entry: field feel [ engage: func [face action event] [ switch/default event/key reduce [ bs [remove back tail face/text] cr [unview] escape [unview] 'left [ system/view/caret: back face/text ; not working ] ] [ append face/text event/key txt/text: face/text ] show face show txt event ] ] ] view/new center-face layout view-block focus entry do-events

This is a little closer to traditional behaviour: switch/default event/key reduce [ bs [system/view/caret: remove back system/view/caret] cr [unview] escape [unview] 'left [ system/view/caret: back system/view/caret ; not working ] ][ system/view/caret: insert system/view/caret event/key txt/text: face/text ] Q. Is there a way to copy the field face object and modify its behavior? What would you do with the copy of the field face? You can just do -- make face [...some changes...] -- within the ENGAGE functions to make a clone. A face is just an object after all. Q. Can I access the string containing the characters showing on the screen? FACE/TEXT is the self same string. Q. Also How to use a face created with make face inside a VID layout? You need to place it inside another face's pane. SOME-FACE/PANE can be a face or a block of faces. Note that View kicks in when you place faces within SYSTEM/VIEW/SCREEN-FACE/PANE (try SOURCE VIEW).

Does this help toward your end goal? R E B O L [] view/new w: layout [ f: field field key #"^[" [quit] key #"^H" [system/view/caret: remove back system/view/caret show w] ] forever [ old: copy f/text if not viewed? w [quit] wait .1 if old <> x: copy f/text [print x] ]

Q. Is there a way to copy the field face object and modify its behavior? What would you do with the copy of the field face? Capture keystrokes before they get to FACE/TEXT

The first solution works great, the additional code is minimal. Why do I need to change txt/text: face/text into txt/text: copy face/text when I use a text field instead of field? view-block: [ txt: text white blue bold 200 entry: field feel [ engage: func [face action event] [ ; -- contributed code switch/default event/key reduce [ bs [system/view/caret: remove back system/view/caret] cr [unview] escape [unview] 'left [ system/view/caret: back system/view/caret ] 'right [ system/view/caret: next system/view/caret ] 'end [ system/view/caret: tail system/view/caret ] 'home [ system/view/caret: head system/view/caret ] ][ system/view/caret: insert system/view/caret event/key txt/text: copy face/text ] ; --- contributed code show face show txt ] ] ] view/new center-face layout view-block focus entry do-events

Without the 'copy', txt/text permanently refers to the text in face/text (if you change txt/text, you're changing that face/text too). By copying face/text, you're referring to the text that's in face/text as that moment.

That's the intended behavior. With txt field txt/text: face/text ; does update txt With txt text txt/text: face/text ; show txt displays nothing txt/text: copy face/text ; does update txt

I tried the first version: 'left [ system/view/caret: back system/view/caret ] It requires to redefine the behavior of every single key, including highlight insert / over ... The second proposed solution can be made to use the native field editing. dirty? allows to find out about each new keystroke: R EBOL [] print "" view/new center-face w: layout [ f: field target: field key #"^[" [quit] ] focus f forever [ if not viewed? w [break] wait .01 if f/dirty? [ either (length? f/text) > (length? target/text) [ action-type: "add char - " ] [ action-type: "modify string - " ] newchar: exclude f/text target/text ; needs fixing print join action-type (newchar) target/text: copy f/text show target f/dirty?: false ] ] I am not 100% sure how if not viewed? w [break] works.

If the Window is closed, the forever loop continues to evaluate and you'll have an invisible Rebol process running, so I put the 'viewed? w' condition to close the process properly.

Without viewed? w field editing locks up. I figured viewed? would become false when closing w. I am yet to comprehend the lockup.