Unit12.pas

unit Unit12;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
  OtlSync, OtlTaskControl, OtlTask, OtlParallel;

type
  TFoo = class
  private
    FTask: IOmniTaskControl;
    FCancellationToken: IOmniCancellationToken;
  public
    constructor Create();
    destructor Destroy(); override;
    procedure RunTask();
  end;

  TForm12 = class(TForm)
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form12: TForm12;

implementation

{$R *.dfm}

{ TFoo }

constructor TFoo.Create;
begin
  FTask := nil;
  FCancellationToken := CreateOmniCancellationToken;
end;

destructor TFoo.Destroy;
begin
  FCancellationToken.Signal;
  FTask.WaitFor(INFINITE);
  inherited;
end;

procedure TFoo.RunTask;
begin
  FTask := CreateTask(
    procedure(const Task: IOmniTask)
    begin
      if (not Task.CancellationToken.IsSignalled) and (not Task.Terminated) then
        Task.Invoke(
          procedure()
          begin
            Assert(Self <> nil, 'AV');
          end);
    end).Unobserved;

  Parallel.Start(FTask, Parallel.TaskConfig.CancelWith(FCancellationToken));
end;

procedure TForm12.FormCreate(Sender: TObject);
var
  F: TFoo;
begin
  F := TFoo.Create;
  try
    F.RunTask;
  finally
    FreeAndNil(F);
  end;
end;

end.