Delphi 异常class 由线程引起的分段(11)？

Question

当 ButtonConnectClick 被激活时，它给出了 Segmentation (11) 异常。我认为是线程中的pocForm1.AddLine('new line by thread');引起的，但我不确定如何解决。

想法是在线程处于活动状态时向备注字段添加行。

unit Unit1;

interface

uses
  System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
  FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs,
  IdBaseComponent, IdComponent, IdTCPConnection, IdTCPClient, FMX.Layouts,
  FMX.Memo, FMX.StdCtrls, IdGlobal, IdIntercept;

type
  TpocForm1 = class(TForm)
    ButtonConnect: TButton;
    ButtonDisconnect: TButton;
    Memo1: TMemo;
    procedure ButtonConnectClick(Sender: TObject);
    procedure ButtonDisconnectClick(Sender: TObject);
    procedure AddLine(text : String);

  private

  public
    { Public declarations }
  end;

  TpocTCPClientThread = class(TThread)
    //TCPClient: TIdTCPClient;
  protected
    procedure Execute; override;
  end;

var
  pocForm1: TpocForm1;

implementation
{$R *.fmx}
var
  thread: TpocTCPClientThread;

procedure TpocForm1.ButtonConnectClick(Sender: TObject);
begin
  Memo1.Lines.Add('Client connected with server');
  thread:= TpocTCPClientThread.Create(False);
end;

procedure TpocForm1.ButtonDisconnectClick(Sender: TObject);
begin
  thread.Terminate;
  thread.WaitFor;
  FreeAndNil(thread);
  Memo1.Lines.Add('Client disconnected from server');
end;

procedure TpocForm1.AddLine(text : String);
begin
  Memo1.Lines.Add(text);
end;


procedure TpocTCPClientThread.Execute();
begin
  while not Terminated do
  begin
    pocForm1.AddLine('new line by thread');
  end;
end;

end.

Answer 1

您不能从主线程外部执行 GUI 代码。您需要确保所有 GUI 代码都在主线程上执行。例如通过调用 TThread.Queue 或 TThread.Synchronize.

Delphi 异常class 由线程引起的分段(11)？

Delphi exception class Segmentation (11) caused by thread?

delphi

multithreading