arrowkey and selectionchanged in a list field
david at dvglasgow.wanadoo.co.uk
Sat Jun 23 06:15:53 EDT 2007
I have a list field containing the names of JPGs. I want the
selected image displayed. This is easy using mouseup or
selectionchanged to trigger the appropriate URL being prepended to
the filename, and the file displayed correctly.
However, I wanted users to be able to arrow up and down through the
field, and the image to change just as if the selection had changed
by being clicked on. Unfortunately, selectionchanged is not sent if
the selection is changed via arrow keys. This is a bit sad, but
documented as normal behaviour. This means you need to catch
arrowkey, and then script accordingly.
I was surprised to discover that the selectedline reported in this
way seems to lag one behind the actual selected line, and display an
image adjacent to the correct one. I put the script in a group
containing the list field, so I expected the selection to have
changed by the time the message reached the group. But it doesn't.
I have worked around it by adding or subtracting one from the
reported selectedline in a switch case structure, but then had to add
script to test whether the tnewselectedline variable would be taken
out of range by the calculation. Happy to have got it working, but I
can't believe there isn't a better way of doing things (- isn't there
always in Rev?).
If the selection change by arrow key triggered the selectionchanged
message, my cludge wouldn't be needed at all. What have other folks
done to achieve the same thing?
Carlton Glasgow Partnership
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