TAdvSTringGrid - SortedRowIndex.

VCL TMS VCL UI Pack
1

When moving a row with ctrl+arrowkey .... SortedRowIndex does not follow the row???


Even doing a new sort - the row will have the SortedRowIndex of the row it replaced.

Is this normal behaviour?
2

Insert and delete row will also show some very strange sortedrowindex values.


3

SortedRowIndex is a snapshot after sorting. Moving, inserting, deleting rows after this is not further synchronized in SortedRowIndex.

4

How do I keep it sync'ed then?

I'm often faced with filling a grid from a TList<TSomething> ... and I need the ability to add, delete and update the elements by their original index.
5

The best way to do this is by adding the unique element ID for example in grid.Objects[col,row] associated with a cell in the row.

6

So you are saying that rowindex (of any kind - realrowindex, sortedrowindex or other) is of no use when I need to keep a grid in sync with a List?

7

If you are doing all kinds of operations like move/insert/delete ...no. If you just sort or hide/unhider row yes.

8

This was an unexpected answer ... 

Investigating further still reveals som disturbing behaviour regarding SortedRowIndex.



unit Unit1;


interface


uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, AdvUtil, Vcl.Grids, AdvObj, BaseGrid, AdvGrid, Vcl.StdCtrls;


type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    AdvStringGrid1: TAdvStringGrid;
    procedure FormCreate(Sender: TObject);
    procedure AdvStringGrid1GetDisplText(Sender: TObject; ACol, ARow: Integer; var Value: string);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;


var
  Form1: TForm1;


implementation


{$R *.dfm}


procedure TForm1.AdvStringGrid1GetDisplText(Sender: TObject; ACol, ARow: Integer; var Value: string);
begin
  if (ARow > 0) and (ACol = 2) then
    Value := IntToStr(AdvStringGrid1.SortedRowIndex(ARow));
  if (ARow > 0) and (ACol = 3) then
    Value := IntToStr(AdvStringGrid1.UnSortedRowIndex(ARow));
  if (ARow > 0) and (ACol = 4) then
    Value := IntToStr(AdvStringGrid1.RealRowIndex(ARow));
end;


procedure TForm1.Button1Click(Sender: TObject);
begin
  AdvStringGrid1.HideRow(AdvStringGrid1.RealRow);
end;


procedure TForm1.Button2Click(Sender: TObject);
begin
  AdvStringGrid1.UnHideRowsAll;
end;


procedure TForm1.FormCreate(Sender: TObject);
begin
  AdvStringGrid1.SortSettings.Show := true;
  AdvStringGrid1.AutoNumberCol(0);
  AdvStringGrid1.RandomFill();
  AdvStringGrid1.Cells[0,0] := 'Init';
  AdvStringGrid1.Cells[1,0] := 'Random';
  AdvStringGrid1.Cells[2,0] := 'Sorted';
  AdvStringGrid1.Cells[3,0] := 'Unsorted';
  AdvStringGrid1.Cells[4,0] := 'Real';
end;


end.

Run and try ...

position on row 5 and press the hide row button.
Result: The row is correct hidden - and values for SortedIndex reflects this. (value is now "gone")

Now Unhide - and press header for Column 1 (Random).
Notice that SortedIndex column values match Init column - all is good.
Now Hide a row !
Result: The row is hidden - BUT SortedIndex column starts having values above 9 ????

Is this still expected behaviour?

9

We've applied a fix for this but the code to be used in the OnGetDisplText should be:


procedure TForm1.AdvStringGrid1GetDisplText(Sender: TObject; ACol,
  ARow: Integer; var Value: string);
begin
  if (ARow > 0) and (ACol = 2) then
    Value := IntToStr(AdvStringGrid1.SortedRowIndex(AdvStringGrid1.RealRowIndex(ARow)));
  if (ARow > 0) and (ACol = 3) then
    Value := IntToStr(AdvStringGrid1.UnSortedRowIndex(AdvStringGrid1.RealRowIndex(ARow)));
  if (ARow > 0) and (ACol = 4) then
    Value := IntToStr(AdvStringGrid1.RealRowIndex(ARow));
end;

With our fix applied, above code will work as expected.
10

Great to hear :-)


Will the fix be included in next update? And/or can I get it via e-mail?

11

A source update is available upon email request