Hi all.
Has anyone tried to determine the index of the next line of a datagrid? It’s
not as straightforward as you might think. When data is first loaded into a
datagrid, the dgIndexes are only going to be in numeric order if the sort order
of the datagrid is the same as the data you are loading. Otherwise, the indexes
will be all mixed up, but the dgLines of the datagrid will ALWAYS be in the
order of the visible rows.
Sure you can just add one to the current dgHilitedLine, but what if you want to
know the index of the next line just before deleting the current one? You
cannot delete the line first because then the line numbers change, and there
won’t be another line hilited until your code sets it.
And while there is a dgIndexOfLine property built in, there is no
dgLineOfIndex! Not only that, but there is a dgIndexes property, but there is
no dgLines property! How odd is that?? The goal is to determine the index of
the next visible line where the line numbers are no longer sequential.
So I wrote some very simple virtual properties that ought to be a part of the
datagrid library. You can put these in the script of a datagrid itself, or if
you are brave enough to use the inline behaviors feature of datagrids as I do,
you can put them in your own datagrid custom library. But really they belong in
the built-in datagrid library itself. They are:
getProp dgNextIndexOfLine [tLine]
put tLine +1 into tNewLine
if tNewLine > the dgNumberOfLines of me then
put the dgIndexOfLine [tLine] of me into tIndex
else
put the dgIndexOfLine [tNewLine] of me into tIndex
end if
return tIndex
end dgNextIndexOfLine
getProp dgPrevIndexOfLine [tLine]
put tLine -1 into tNewLine
if tNewLine <1 then
put the dgIndexOfLine [tLine] of me into tIndex
else
put the dgIndexOfLine [tNewLine] of me into tIndex
end if
return tIndex
end dgPrevIndexOfLine
You are welcome. :-)
Bob S
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