Am 07.01.2013 um 18:33 schrieb 土卜皿 <pengcz.nwpu@gmail.com>:

> hi, all
>    in Hans Hagen's "Metafun context mkiv" page 208, there is some buttons example, I want to know how to implement a complete buttons in context, Thanks in advance!
> 
>   another, in Presentations (screen documents), there is three examples, but they are not able to be compiled by the latest context version 2012.12.28 20:30, I hope to get some advanced examples

Can be a problem with uniqueMPgraphic because useMPgraphic works.

\startuseMPgraphic{wrong or right}
	pickup pencircle scaled 3pt ;
	path p ; p := unitsquare
		xscaled OverlayWidth yscaled OverlayHeight ;
	fill p withcolor .8white ;
	draw p withcolor .625red ;
\stopuseMPgraphic

\defineoverlay[button][\useMPgraphic{wrong or right}]
\setupbuttons[background=button,frame=off]

\setupinteraction[state=start]

\starttext

\completecontent

\page

\hbox
  {\button {previous}          [previouspage]\quad
   \button {next}              [nextpage]\quad
   \button {index}             [index]\quad
   \button {table of contents} [content]}

\completeindex

\stoptext

Wolfgang