dbcombobox - populating dropdown list from a query and AutoComplete
lazarus / 16-Databases

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percentage · 2015-09-01 13:35

I want to populate a dbcombobox dropdown list with the result of a
query that searches for what the user typed in it. I wrote this in its
OnChange event:

Code: [Select]Query.Close;
Query.SQL.Clear;
Query.SQL.Text := 'SELECT IDX, X FROM Y WHERE X LIKE ' +
QuotedStr(DBCombo.Text + '%');
Query.Open;

DBCombo.Items.Clear;
while not Query.EOF do begin
  DBCombo.Items.Add(Query['X']);
  Query.Next;
end;
AutoComplete and AutoDropDown is true. Style: csDropDown. Every time I
try to write something and press a key, the dropdown list is populated
but appears then disappears, and the match for that letter is
autocompleted. I can't write more than one letter, this happens every
time I press a key. How do I get the default behavior?

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taazz · 2015-09-01 13:54

use a dblookupcombo instead

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percentage · 2015-09-01 15:03

From what I understand, the ListSource dataset for a dblookupcombobox
has to be loaded all at once. In my case it could become too big and
slow the application. So I want to retrieve the list items only as
needed and only as many as needed.