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Re: Dynamic evaluation not automatically enabled in CDF documents

• To: mathgroup at smc.vnet.net
• Subject: [mg121893] Re: Dynamic evaluation not automatically enabled in CDF documents
• From: A Retey <awnl at gmx-topmail.de>
• Date: Thu, 6 Oct 2011 04:20:47 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <j6h2vk$6t1$1@smc.vnet.net>

Am 05.10.2011 10:03, schrieb Jacopo Bertolotti:
> Dear Mathgroup,
> Recently I started to use the CDF format from Mathematica to create some
> physics interactive tutorial but, on the last one I created, I
> encountered a strange problem. If you download the cdf
> (http://www.jacopobertolotti.com/CDF/COPS_tutorial_digitalholography.cdf) and
> open it with the offline player you are greeted with the warning that
> "This file contains potentially unsafe dynamic content". If you press on
> "Enable Dynamics" then everything works fine.

If you open the cdf with Mathematica 8, the header (=DockedCell) that it 
shows has also a link which gives details about that security feature. 
There you will find the information that it depends on what 
functionality you use in your cdf-file whether or not that warning is 
shown. If you click on that link  and scroll down the help page that 
opens there is a relatively vague description on what is considered to 
be "unsafe":


Dynamic content is considered unsafe if it:
  uses File operations
  uses interprocess communication via MathLink Mathematica Functions
  uses JLink or NETLink
  uses Low-Level Notebook Programming
  uses data as code by Converting between Expressions and Strings
  uses Namespace Management
  uses Options Management
  uses External Programs

I didn't inspect your code in detail, but it doesn't look very unsafe to 
me. My guess is that it is the Needs for PlotLegends that causes the 
warning in your case. So if you find a way to avoid the use of 
PlotLegends that might solve your problem.

> Yet when the cdf is embedded in a webpage
> (http://www.jacopobertolotti.com/tutorials_digitalholography.html) all
> the Manipulate[] that make a cdf really worth to use are just disabled
> and appear as grey boxes.

I think that this is the default behaviour when shown within the plugin 
when the standalone player would show the "potentially unsafe content" 
warning. If you can't get rid of the warning, your users could still use 
the cdf if they save it to file from the plugin and then open the file 
with the standalone player and allow the potentially unsafe dynamics to 
evaluate. You could put that information into the cdf-file or onto the 
web-page where your users download the cdf-files.

> What puzzles me is that I did not encounter this problem in my previous
> attempts and this time I did not do anything very different (apart from
> the fact that the code is a lot more complex).

as said above, that might well be the cause for the warning...

> Does anybody have any idea how to set the dynamics as enabled by default?

I think that the only solution is to not use anything that is considered 
"unsafe". This might need some experimentation, since I think there is 
no complete list of functions that are considered unsafe. The most 
user-friendly feature would be a tool that would show unsafe content 
with possible alternatives, as the version 5 to version 6 converter, but 
I don't think anything like that does exist...

hth,

albert