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selecting a column in a grid

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  • Subject: [mg98160] selecting a column in a grid
  • From: "Paul Ellsmore" <paul.ellsmore at>
  • Date: Wed, 1 Apr 2009 05:54:45 -0500 (EST)



I have a tricky problem with a graphical user interface. I have a grid of
data, and I want to be able to MouseClick in the grid to either select a row
or a column. Using GUIKit, this is trivial, but I want to be able to
distribute my program using PlayerPro, which won't support GUIKit.


Selecting a row is straightforward using EventHandler and
EventHandlerScaled, since I know how many rows there are and they are all
one line in height. However, the column widths change according to the data,
since I have set ItemSize to Auto. So is there some way of retrieving the
actual values used in ItemSize, when Auto is used? I have tried
CurrentValue[ItemSize] in many variations, but it always fails. 


I could, of course, look at the data that will be in the grid, and compute
the widths of each column accordingly, and synthesize the values that
ItemSize will take. To do that, though, I would need to know what the pixel
width of a particular text string will be, which varies with font family,
size etc. Is there an easy way to do this? This is essentially what
Mathematica does when ItemSize is set to Auto, but I have no idea how to do
it myself.


Currently I have EventHandler wrapped around the whole grid. Is it possible
to wrap it around each individual cell in a grid? I have tried a few ideas,
but they don't seem to work. The documentation suggests that EventHandler
can be wrapped around any expression, but that doesn't seem to be the case,
or at least the wrapped expression doesn't seem to display properly inside
other constructs, such as Grid, Column etc.


Is there some better approach I could take, rather than using EventHandler? 


All ideas gratefully received.






Dr. Paul A. Ellsmore


Nanion Limited

Oxford Centre for Innovation

Mill Street


United Kingdom



Tel: +44 (0) 1865 811175

Fax: +44 (0) 1865 248594


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