popup Memo in FNCGrid

I set in a TMSFNCGrid Grid.Columns[6].Editor:=etMemo;
If the user is in EditMode and comes to this field in the grid then a PullDown Window should appear in this Column to edit some Lines of Text.
At the Moment there are only a edit-Field with only one Line.

Is this possible with etMemo or have i use the RTF Editor for this ?

etMemo is not providing a popup/dropdown window. If you want to achieve this, you will need to add a custom editor. You can for example use the TAdvMemoDropDown control in combination with etCustom:

procedure TForm1.FormCreate(Sender: TObject);
  TMSFNCGrid1.Columns[1].Editor := etCustom;

procedure TForm1.TMSFNCGrid1CellEditGetData(Sender: TObject; ACol,
  ARow: Integer; CellEditor: TWinControl; var CellString: string);
  if CellEditor is TAdvMemoDropDown then
    (CellEditor as TAdvMemoDropDown).MemoText.Text := CellString;

procedure TForm1.TMSFNCGrid1CellEditSetData(Sender: TObject; ACol,
  ARow: Integer; CellEditor: TWinControl; var CellString: string);
  if CellEditor is TAdvMemoDropDown then
    CellString := (CellEditor as TAdvMemoDropDown).MemoText.Text;

procedure TForm1.TMSFNCGrid1GetCellEditorCustomClassType(Sender: TObject; ACol,
  ARow: Integer; var CellEditorCustomClassType: TTMSFNCGridEditorClass);
  if ACol = 1 then
    CellEditorCustomClassType := TAdvMemoDropDown;

Thank you Pieter you are my Hero

Thats what i need:
Initialization, Events and Casting-Syntax

But i see in my Program i used a TAdvStrinGrid and the Eventnames and all other names are not similar.
Would you be so kind an show me the same for a ADVStringGrid ?

Thankyou for your help!

In Holgers new Book i see that there ist an editortype edMemoDropDown and he set the editortype in the event GetEditorType not in form.show. (I dont need to change the editortyp for the memo column)
Is that what i am looking for if i want a user to write Text in more then one Line ?

Yes, edMemoDropDown is doing exactly the same for TAdvStringGrid

Please a sample like your first post for AdvStringGrid.
There are no "Grid1.Columns[1].Editor" in advStringGrid
or the other eventnames

procedure TForm1.AdvStringGrid1GetEditorType(Sender: TObject; ACol,
  ARow: Integer; var AEditor: TEditorType);
  AEditor := edMemoDropDown;

The event GetEditorType is the one i have found and used before but
I hoped that there are somthing like (TMSFNCGrid1.Columns[1].Editor := etCustom;)
i can use in my GridInit Procedure, to initialize this only once.

what is the equivalent to

in AdvStringGrid

There is no need for the other events if you specify edMemoDropDown, the grid will handle everything internally.

Its my fault, i used the wrong Column. (I had some hidden Columns in the Grid)
But now i get the problem when i get out of the memo clicking on the ArrowDown obove, the program jumps to the first Tab of my AdvOfficePager.
What is the event when leaving the Memo ?
Is there a Key to save and go out of the Memo ?
ctrl-W like in normal memos dont work.

I get an Exception EOLeSysError "Die angeforderte Resource wird bereits verwendet" after closing the Memobox.
Then the program go to the event EditingDone

Clicking the arrow button of the memo does not automatically focus the first tab of the pager, we have tested this in a new project. You can press F4 to enter or close or ESCAPE to close the memo dropdown window. We are also not able to reproduce the exception. Can you reproduce this in a new project? Perhaps send us the project so we can investigate this here?

I will try to simulate the Problem in a separate Project with my Configuration. Thanks.
New Information:
When i press F4 in the popup-Memo Windows the Error is befor the Debugpoint in OnEditingDone.
When i press ESC in the popup-Memo Windows the Error is after the Debugpoint in OnEditingDone.

With a default TAdvStringGrid on the form and the code:

procedure TForm1.AdvStringGrid1EditingDone(Sender: TObject);
  outputdebugstring('editing done');

procedure TForm1.FormCreate(Sender: TObject);
  advstringgrid1.Options :=  advstringgrid1.Options + [goEditing];
  advstringgrid1.DefaultEditor := edMemoDropdown;

no error can be seen.
So, you must have settings or code that affects this.
Please isolate this and send a sample source project + steps with which the problem can be reproduced.