unit uDADatasetProvider;

{----------------------------------------------------------------------------}
{ Data Abstract Library - Core Library                                       }
{                                                                            }
{ compiler: Delphi 6 and up                                                  }
{ platform: Win32                                                            }
{                                                                            }
{ (c)opyright RemObjects Software. all rights reserved.                      }
{                                                                            }
{ Using this code requires a valid license of the Data Abstract              }
{ which can be obtained at http://www.remobjects.com.                        }
{----------------------------------------------------------------------------}

{$I DataAbstract.inc}

interface

uses
  Classes, DB, Provider, uDADataTable;

type
  { TDADatasetProvider }
  TDADatasetProvider = class(TDataSetProvider)
  private
    fDataTable: TDADataTable;
    procedure SetDataTable(const Value: TDADataTable);
    function GetDataset: TDataset;

  protected
    procedure Notification(AComponent: TComponent; Operation: TOperation); override;
    function InternalGetRecords(Count: Integer; out RecsOut: Integer;
      Options: TGetRecordOptions; const CommandText: WideString;
      var Params: OleVariant): OleVariant; override;

  published
    property Dataset: TDataset read GetDataset;
    property DataTable: TDADataTable read fDataTable write SetDataTable;
  end;


implementation

{ TDADatasetProvider }

function TDADatasetProvider.GetDataset: TDataset;
begin
  result := NIL;
end;

function TDADatasetProvider.InternalGetRecords(Count: Integer;
  out RecsOut: Integer; Options: TGetRecordOptions;
  const CommandText: WideString; var Params: OleVariant): OleVariant;
begin
  if not DataTable.Active then DataTable.Open;
  
  result := inherited InternalGetRecords(Count, RecsOut, Options, CommandText, Params);
end;

procedure TDADatasetProvider.Notification(AComponent: TComponent;
  Operation: TOperation);
begin
  inherited;

  if (Operation=opRemove) then begin
    if (aComponent=fDatatable) then fDataTable := NIL;
  end;
end;

procedure TDADatasetProvider.SetDataTable(const Value: TDADataTable);
begin
  fDataTable := Value;
  if (fDataTable<>NIL) then begin
    fDataTable.FreeNotification(Self);
    inherited Dataset := fDataTable.Dataset;
  end;
end;

end.