红鱼儿

统计

终止TTask.Run启动的线程
unit Unit15;

interface

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

type
  TForm15 = class(TForm)
    Button1: TButton;
    kbmMWClientTransactionResolver1: TkbmMWClientTransactionResolver;
    Button2: TButton;
    Label1: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    FTaskIsRunning: boolean;
    cnt: Integer;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form15: TForm15;

implementation

{$R *.dfm}

procedure TForm15.Button1Click(Sender: TObject);
begin
  FTaskIsRunning := true;
  TTask.Run(
    procedure
    begin
      while FTaskIsRunning do
      begin
        sleep(99);
        TThread.Synchronize(nil,
          procedure
          begin
            Label1.Caption := 'Thread is running...' + cnt.ToString;
            inc(cnt);
          end);
      end;//end while.
    end);

end;

procedure TForm15.Button2Click(Sender: TObject);
begin
  FTaskIsRunning := false;
  cnt := 0;
end;

procedure TForm15.FormCreate(Sender: TObject);
begin
  FTaskIsRunning := false;
  cnt := 0;
end;

end.

上面的代码,运行正常,按Button1开启一个线程,Button2终止线程运行。这是一个VCL项目。可以看到用一个私有变量FTaskIsRunning来控件线程中的循环。这个实现是在一个Form中,运行正常,现在换成TFrame中实现,基本上是复制Form中的实现代码,可以忽略不看。

unit Unit16;

interface

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

type
  TFrame16 = class(TFrame)
    Label1: TLabel;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    FTaskIsRunning:boolean;
    cnt:Integer;
  public
    { Public declarations }
  end;

implementation

{$R *.dfm}

procedure TFrame16.Button1Click(Sender: TObject);
begin
  FTaskIsRunning := true;
  TTask.Run(
    procedure
    begin
      while FTaskIsRunning do
      begin
        sleep(99);
        TThread.Synchronize(nil,
          procedure
          begin
            Label1.Caption := 'Thread is running...' + cnt.ToString;
            inc(cnt);
          end);

      end;
    end);
end;

procedure TFrame16.Button2Click(Sender: TObject);
begin
  FTaskIsRunning := false;
  cnt := 0;
end;

end.

然后,把Frame放到Form上运行,结果也正常。

将上面的Frame+Form的实现方式,换成FMX项目,在Android,Win32平台运行,也正常。

posted on 2019-02-12 23:27  红鱼儿  阅读(...)  评论(...编辑  收藏