🚀 go-pugleaf

"Dan" <Dan@do.not.spam> wrote in message
news:46854789.701@do.not.spam...

> The above doesn't work. Indeed it creates the image that the gridis
> cleared and it 'looks' like everything is gone, but simply set the
> Row/Column count back again and you will see that the strings that
were
> entered into the grid are still there.

Looking at the source code for TStringGrid, I do not see it ever
shrinking the memory used for the Rows and Cols until the TStringGrid
is destroyed.  The memory only grows when needed.

> Even the above though takes nearly 10 seconds to clear a Grid
> containing 275K rows

You should not be using a TStringGrid to display that many rows to
begin with.  It is not designed to handle large amounts of data.  I
would suggest using a virtual TListView instead (set the OwnerData
property to True and use the OnData event).  Then you can perform your
own data management and optimize it for better speed and efficiency
since the data is decoupled from the UI.

> Am I wrong to expect that this clearing process should be possible
> in less than a second?

Yes.  TStringGrid is not designed for large amounts of data.  There is
a lot of maintenance going on internally, so it is going to slow down
the more data you put into it.


Gambit