# [NTG-context] add more blank space when using \starteffect[hidden]

Hans Hagen j.hagen at xs4all.nl
Sat Mar 13 10:18:36 CET 2021

On 3/12/2021 10:08 PM, Jeong Dal wrote:
> Hi,
>
> Sometimes, I need to hide the solution of a problem.
> So I use \doifmode{} and \starteffect[hidden] as in the following sample
> file.
> Since I want to set more blank space if it is hidden, I add \blank[5cm]
> when it is in the \enablemode[hideSolution].
> It works well except the figures and bars are not hidden. Only texts,
> even  in the mp part, are hidden.
> It is OK for me.
>
> However, it would be much better to set the height of blank space
> depends on the height of hidden texts.
> Is there a way to set the variable height  using “overlay” stuff instead
> of \blank[5cm]?
>
>
> Best regards,
>
> Dalyoung
>
>
> \startbuffer[circles]
> draw fullcircle scaled 1cm;
> draw fullcircle scaled 1cm shifted (2cm,0);
> dotlabel.top(“O”,origin);
> \stopbuffer
>
> \def\StartHide{\doifmode{hideSolution}{\starteffect[hidden]}}
> \def\StopHide{\doifmode{hideSolution}{\stopeffect\blank[5cm]}}
>
> %\enablemode[hideSolution]
>
> \starttext
> \framed[]{This is what I want:}
> \framedtext[]{
> \StartHide
> \samplefile{knuth}
> Overbar is not \overbar{hidden}.
> {\processMPbuffer[circles]}
> \StopHide
> }
> \stoptext
In your case it's easier than you mightt think:

\framedtext[empty=yes]

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