ActionScript Dictionaries
May 3, 2012 Leave a comment
Question: In the context of Training Studio 2.0 templates, I am unclear on the full meaning of “dictionary.” Specifically, I am curious what this statement in the documentation means: The pageArrayLocal variable is a Dictionary that represents the current training page.
Answer: A Dictionary is actually a Flex/ActionScript object. It is similar to a Hashtable in Visual Basic or an associative array in JavaScript. The Dictionary has a key and a value. When we read the content.xml file in Training Studio, we put the content of each page into its own Dictionary.
The keys are column names and the values are the text that the subject matter put in. For example, here is a small section of the XML for a page:
<title>Training Studio TBCON Faculty Sample</title> <content_0>Welcome to the TBCON Faculty sample created in the Platte Canyon Training Studio. To learn more about Training Studio, please visit ~external=http://www.trainingstudio.net~www.trainingstudio.net~.</content_0> < <graphic_0>trainingstudio.gif</graphic_0>
title, content_0, and graphic_0 are keys. “Training Studio TBCON Faculty Sample”, “Welcome…”, and “trainingstudio.gif” are values.
When Training Studio navigates to a page, it sets the pageArrayLocal variable to be the Dictionary associated with that page. We then look for the “templateType” key to figure out which template to use. Within the template, the loadData method loops through the keys and sets the appropriate content, reads in the media, load graphics, etc.
A related data type that you’ll run into is the ArrayCollection. It is similar to a Dictionary but does not have keys. Instead you refer to objects by their numeric position. In Training Studio, the TSCommon.masterContentArray is an ArrayCollection of all the Dictionaries (one per page) in the training.
See the next post for the equivalent objects in .NET.
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