Hi,
 
I've tried Hans' example introduced at mwidget-p.pdf, it's perfect. But when I was trying some subpage arrangements, it just failed. How could it happen? I guess either shiping out subpages forget the fields or something has covered over them. Here's a small example (by the way, I don't actually know the meanings of the arguments of \dosetuparrangement, I'm very appreciated if someone could explain the macro to me.):
 
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\setupinteraction  [state=start]

\installpagearrangement TEMP
  {\dosetuparrangement{1}{1}{1}{0}{0}%
     \pusharrangedpageTEMP\poparrangedpagesAonly\relax}

\def\pusharrangedpageTEMP#1%
  {\doglobal\increment\arrangedpageN
   \reportarrangedpage\arrangedpageN
   \ifcase\arrangedpageN
   \or \handlearrangedpageXandY{#1}0{11}0\arrangedpageA
   \or \handlearrangedpageXandY{#1}0{9}0\arrangedpageA
   \or \handlearrangedpageXandY{#1}0{7}0\arrangedpageA
   \or \handlearrangedpageXandY{#1}0{5}0\arrangedpageA
   \or \handlearrangedpageXandY{#1}0{3}0\arrangedpageA
   \or \handlearrangedpageXandY{#1}0{1}0\arrangedpageA
     \poparrangedpages
   \fi}

\def\poparrangedpagesAonly
  {\ifnum\arrangedpageN>\zerocount
     \dontcomplain
     \paperwidth\arrangedpageX\paperwidth
     \paperheight\arrangedpageY\paperheight
     \outputarrangedbox\arrangedpageA
     \doglobal\newcounter\arrangedpageN
   \fi}

\definepapersize
  [Column]
  [width=40pt,
   height=400pt,
   offset=0pt]

\definepapersize
  [Scroll]
  [width=540pt,
   height=400pt,
   offset=0pt]


\setuppapersize    [Column][Scroll]
\setuparranging    [TEMP,background]
\setuplayout
  [margin=0pt,
   width=fit,
   height=middle,
   leftmargin=0pt,
   rightmargin=0pt,
   leftedge=0pt,
   rightedge=0pt,
   header=0pt,
   footer=0pt,
   bottom=0pt,
   top=0pt,
   backspace=0pt,
   topspace=0pt,
   bottomspace=0pt,
   horoffset=0pt,
   veroffset=0pt,
   headerdistance=0pt,
   footerdistance=0pt,
   topdistance=0pt,
   bottomdistance=0pt]

\pdfoptionpdfminorversion=6

\title{What?}

\starttext

\newcounter\abc
\doglobal\increment\abc

\setupfields
[reset]
\setupfield
[HelpSetup]
[width=1.2em,height=fit,frame=off,option={readonly,hidden}]

\def\currenthelp{Help::\abc}

\definefield [\currenthelp] [check] [HelpSetup] [helpinfo\abc] [helpinfo\abc]

\definesymbol [helpinfo\abc] [\SomeHelpText]
\def\SomeHelpText%
{\framed
[width=1.2em,height=fit,align=middle,style=small,
frame=on,background=color,backgroundcolor=white,framecolor=red]
{Some texts}}

\inright{\fitfield[\currenthelp]} Click \goto{here}[JS(Toggle_Hide{\currenthelp})] to see.

\dorecurse{10}{\input knuth\endgraf}

\stoptext

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--
Sincerely yours,
Chen
----------------------------------------------------------------

          Zhi-chu Chen | Shanghai Synchrotron Radiation Facility
         No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China
             tel: 086 21 5955 3405 | zhichu.chen.googlepages.com
                                               | www.sinap.ac.cn
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