Setting StringGrid Columns Property Kills Data Load Process
lazarus / 10-Designer

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flywire · 2015-03-14 11:34

I am working on this form: http://forum.lazarus.freepascal.org/index.p
hp/topic,27663.msg171291.html#msg171291 which is basically just a
simple TStringGrid with the program in the post below it.

When I change the StringGrid Columns Property and add
StringGrid.Columns properties the data load process generates an error
and will not run. Any thoughts? Is is simply that the Column Title is
different to the (numeric) Column Title assigned in the program?

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Blaazen · 2015-03-14 12:13

There should be no difference in normal/Columns approach if you
access the cells with Cell[x, y];. Title cells are normal cells, only
they can have their own font-setting or image. You can remove them by
setting FixedRows:=0;.

What error message you got?

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flywire · 2015-03-14 12:20

After adding just one column the title becomes Title and the Error
message is "Use Columns property to add/remove columns." OK/Cancel
etc.

Object Inspector, StringGrid1, Properties, Columns ... Add, close
down, compile, run - error.

Maybe I set it to a single column so that the program can't process
all of the columns? I wouldn't have thought so though.

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Blaazen · 2015-03-14 12:36

Now I see. When you use columns, you cannot simply change property
ColCount of the grid. You have to add/delete columns from collection,
i.e.:
Instead of
Code: [Select]ColCount:=ColCount+1;use
Code: [Select]Columns.Add;And similar for delete, insert, move,
exchange etc.

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flywire · 2015-03-14 12:45

I am not quite clear. The code works until I change the column
properties and if I delete the property then the code works again.

What exactly happens when I set columns through the Object Inspector?

Are you saying that when I use Columns in the Object Inspector to set
Columns then I need to change the code? I assume that this setting
disables the methodology used in the code to add columns. Can I just
make sure that the number of columns match?


Is there a better way to set column labels, visibility etc?

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flywire · 2015-03-14 12:58

OK I replace
Code: [Select]StringGrid1.ColCount := 42 + 1;
with
Code: [Select]Columns.Add;inside the loop.

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Blaazen · 2015-03-14 13:59

When you start to use Columns, property ColCount become "readonly".

You can also read Columns.Count.

Once you use Columns, you are allowed to change number of columns only
via Columns.Add, Columns.Delete, Columns.Insert or Columns.Clear.

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flywire · 2015-03-14 20:40

Quote from: Blaazen on March 14, 2015, 02:59:00 pmWhen you start to
use Columns, property ColCount become "readonly". ...

Ahhh ... as long as I don't write ColCount in code then it should be
fine. Easy fix.

edit: typo.

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flywire · 2015-03-15 06:46

OK I replaced
Code: [Select]StringGrid1.ColCount := 42 + 1;
with
Code: [Select]// StringGrid1.ColCount := 42 + 1;
done.