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

Figure 6: A resource file defining blocks of images.
image1.jpg
image2.gif
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So for example a block could be used to group an image filename with an image title – a number of file/title pair
blocks can be created, then the order of the blocks can be randomised (between blocks) and each slide imports
two resources from the resource set; one into an image component, and the second into a text component which
describes the image displayed.
5.4.3 Overriding component properties
As well as defining the id attribute of each resource, you can define an arbitrary number of additional attributes.
These additional attributes represent properties of the component into which the resource gets imported, and
can be used to override any default properties of that component. An example of this approach is shown in
figure 7.
Figure 7: Resources which define additional attributes to override defaults in the timeline sequence.
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BLUE
GREEN
This illustrates one way in which a Stroop task could be constructed. If the resources in this example are
imported into text components, two different results would be produced; one with the word BLUE in yellow, the
other with the word GREEN in red. An experimental template only needs to describe a single text component
with an import tag, and on each slide with this component, the result will be different.
Any other properties of the target component may also be overridden, such as height, width, bgcolor, even
type. All applicable properties you define in a resource will be coerced into the target component; any which
are not appropriate will have no effect. If you do not specify content for a resource but instead leave it empty,
for example , the experiment will use whatever is already defined in
a tag in the experiment file. This behaviour can be used to display the same word repeatedly but
in different colours. The word is defined once in the text component in the timeline, while the changing colours
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