Self在Delphi中挂起一个不需要的线程并安全恢复

TThread.Suspend;

TThread.Resume;

TThread.Synchronize(nil, procedure
begin
  TThread.Resume;
end);

unit MainForm;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TMyThread = class(TThread)
  protected
    procedure Execute; override;
  end;

  TForm1 = class(TForm)
    btnStart: TButton;
    btnSuspend: TButton;
    btnResume: TButton;
    procedure btnStartClick(Sender: TObject);
    procedure btnSuspendClick(Sender: TObject);
    procedure btnResumeClick(Sender: TObject);
  private
    FMyThread: TMyThread;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TMyThread.Execute;
begin
  while not Terminated do
  begin
    Sleep(1000);
    TThread.Queue(nil, procedure
    begin
      Form1.Caption := 'Thread is running';
    end);
  end;
end;

procedure TForm1.btnStartClick(Sender: TObject);
begin
  FMyThread := TMyThread.Create(True);
  FMyThread.Start;
end;

procedure TForm1.btnSuspendClick(Sender: TObject);
begin
  TThread.Suspend;
  TThread.Synchronize(nil, procedure
  begin
    Form1.Caption := 'Thread is suspended';
  end);
end;

procedure TForm1.btnResumeClick(Sender: TObject);
begin
  TThread.Resume;
  TThread.Synchronize(nil, procedure
  begin
    Form1.Caption := 'Thread is running';
  end);
end;

end.