Author: Tomas Rutkauskas

I wish to display a list. I can easily create the list by adding to Items. 
Optionally the user can add an item to the list. When I tried it, the OnChange 
event fired as soon as I pressed one key. I tried using the OnExit - this crashed 
the app. How can the user type in a string and press Enter and get this added to 
the list and selected?

Answer:

By unassigning and re-assigning the OnChange event handler for the combobox. 
Example:

1   procedure TForm1.Button1Click(Sender: TObject);
2   begin
3     if Trim(Edit1.Text) <> EmptyStr then
4       if ComboBox1.Items.IndexOf(Edit1.Text) = -1 then
5       begin
6         ComboBox1.OnChange := nil;
7         ComboBox1.Items.Add(Edit1.Text);
8         ComboBox1.ItemIndex := ComboBox1.Items.IndexOf(Edit1.Text);
9         ComboBox1.OnChange := ComboBox1Change;
10      end;
11  end;