Title: How to freeze a Control
Question: sometimes you must freeze a control or the hole form to
avaoid flickering.
Answer:
procedure LockControl(c: TWinControl; lock: boolean);
begin
if (c = nil) or (c.Handle = 0) then exit;
if lock then SendMessage(c.Handle, WM_SETREDRAW, 0, 0)
else begin
SendMessage(c.Handle, WM_SETREDRAW, 1, 0);
RedrawWindow(c.Handle, nil, 0,
RDW_ERASE or RDW_FRAME or RDW_INVALIDATE or RDW_ALLCHILDREN);
end;
end;
// note: i have found this procedure in a delphi newsgroup;
// thanks to the unknown author. (TeamB ?)
make shure to use this function in a try ... finally construct
or you may see your control never again.
example:
LockControl(Form1.ListView1, True);
try
// now work with the ListView1
for i:= 1 to 1000 do
Form1.ListView1.Items.Add(.....
finally
LockControl(Form1.ListView1, False);
end;