Marty, I am no expert but let me share what I have learned over the past few
weeks.
Don't be too concerned about the database examples. Look at the message
handler carefully.
command GetDataForLine pLine, @pDataA
On every call to this handler the DataGrid is asking you to provide the data
for just one row and the identifer of this row is pLine. So you just need to
be able to return only the data associated with that one row. How you do this
is up to you. Each row could be as simple as a line in a field. You just have
to put the data from line into an array and return it in pDataA.
As the datagrid is scrolled around, it will call GetDataForLine when it
anticipates the need for data. It looks like the dataGrid requests a few extra
rows that are not visiable to make sure that scrolling looks smooth. So if 10
rows are visiable the datagrid is asking for 12 or so worth of data.
You will start getting GetDataFOrLine message as soon as you set
dgNumberOfRecords. All of the rows when using this technique are fixed height
rows. The datagrid must assume this to figure out the size of the scroll area.
I have a situation where I saved to dgVScroll in a custom property of the
card in the close card hander as well as clearing the datagrid. I reload the
datagrid in the open card handler an re-set the dgvScroll and the datagrid is
in the same location as before leaving the card.
To answer your questions directly:
The dgNumberOfRecords should be set to the total number of records in my data
set, correct? Correct
In my scenario, how do I use the "GetDataForLine" command? I hope I was clear
enough above
Am I wasting time by converting my tab-delimited file to an array? Yes, I
don't see the need. You build pDataA within the GetDataForLine handler.
Regards,
Mike
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