WebExp2 Experimenter's Manual - School of Informatics - University ...

Figure 22: HTML to include the experimental applet in a web page.
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6.4.2 Javascript and the browser
The section of the applet tag definition between tags may appear confusing. This is a bit of javascript
which will write another tag into the HTML, describing which browser the participant is using.
The most reliable way of finding out what type of browser the participant is using is by querying the browser
itself with javascript; it cannot be done in Java. This bit of code does that and writes the result to the HTML
page so you get something like . The actual value is far more
lengthy, but you can usually ascertain the source browser from the name near the end of the value, or failing
that the generic name near the start.
Therefore you don’t need to worry about this code or how it works, just include it if you want to know what
browser is being used to view your experiment. The value is added to the results and recorded in the subject
results file.
6.4.3 Applet attributes and parameters
When you include the tag in your webpage, there are two groups of settings to configure. Firstly there
are the attributes of the applet, which are defined in the opening tag; these are properties which relate directly
to the applet. Secondly there is the set of parameters, which define properties which the WebExp2 client itself
can read and use.
Applet attributes The attributes define basic features of the applet. They are of the form attribute=”value”
and are specified in the opening tag.
To centre an applet horizontally in the page, surround the element with tags.
The codebase attribute is only necessary if the root release directory (with the jar file and data) is different
from the directory containing the webpage. If your webpages are hosted outside of the release directory, then
you should specify the codebase attribute. For this reason, it is easiest when testing your experiments to place
their supporting HTML pages in the release directory and run them from there, so the codebase tag does
not need to be defined. Note that the webpages may be hosted separately from WebExp2, in which case the
codebase should specify the full path of the server and directory containing WebExp2.
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