Hilos.... TThreads... Uff...

[craven]

Hola amigos, a ver si podeis echarme una manilla con esto. Vereis, he diseñado un objeto que, a grosso modo, tiene la siguiente estructura.

TMiObjeto = class
private
proceso : TThread ;
...
...
public
...
procedure funciona ;
...
end ;

Me gustaria que cuando se ejecute el procedimiento FUNCIONA, se cree la hebra PROCESO y se ejecute el código que ésta contiene, pero no se cómo hacerlo. A ver si podeis ayudarme. Gracias de antemano. Un saludo.

[delphi.com.ar]

Hola craven, te cuento que en la ayuda de TThread tienes un ejemplo que hace algo muy similar a lo que tu pides, la única gran diferencia es que la clase ancestro es un TForm y es un poco mas complejo el código porque hay 4 threads.

Saludos!

[craven]

Hola .... Pero, ¿donde esta exactamente el ejemplo? Gracias.

[delphi.com.ar]

Ok... no lo encuentro en la ayuda de Delphi 7, pero te paso lo que está en la del 5

unit Pg1;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
StdCtrls, ComCtrls, ExtCtrls, Pg2;

const
WM_ThreadDoneMsg = WM_User + 8;

type
TForm1 = class(TForm)
ProgressBar1: TProgressBar;
ProgressBar2: TProgressBar;
Button1: TButton;
Button2: TButton;
TrackBar1: TTrackBar;
TrackBar2: TTrackBar;
Bevel1: TBevel;
Bevel2: TBevel;
Label1: TLabel;

Label2: TLabel;
Button3: TButton;
Button4: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure Button4Click(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure TrackBar1Change(Sender: TObject);
procedure TrackBar2Change(Sender: TObject);
procedure FormDestroy(Sender: TObject);

private
{ Private declarations }
MyThread1 : TMyThread; // thread number 1
MyThread2 : TMyThread; // thread number 2
Thread1Active : boolean; // used to test if thread 1 is active
Thread2Active : boolean; // used to test if thread 2 is active
procedure ThreadDone(var AMessage : TMessage); message WM_ThreadDoneMsg; // Message to be sent back from thread when its done
public
{ Public declarations }

end;

var
Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject); // Create Thread 1
{ The thread will destroy iteself when it is done executing because FreeOnTerminate is set to true.
The first paramter is the priority, and the second is the progressbar to update.
}
begin
if (MyThread1 = nil) or (Thread1Active = false) then // make sure its not already running

begin
MyThread1 := TMyThread.CreateIt(TrackBar1.Position, ProgressBar1);
Thread1Active := true;
end
else
ShowMessage('Thread still executing');
end;

procedure TForm1.Button2Click(Sender: TObject); // Create Thread 2
begin
if (MyThread2 = nil) or (Thread2Active = false) then // make sure its not already running
begin
MyThread2 := TMyThread.CreateIt(TrackBar2.Position, ProgressBar2);

Thread2Active := true;
end
else
ShowMessage('Thread still executing');
end;

procedure TForm1.Button3Click(Sender: TObject); // Terminate Thread 1
begin
if (MyThread1 <> nil) and (Thread1Active = true) then // check to see if it is running
MyThread1.Terminate
else
ShowMessage('Thread not started');
end;

procedure TForm1.Button4Click(Sender: TObject); // Terminate Thread 2

begin
if (MyThread2 <> nil) and (Thread2Active = true) then // check to see if it is running
MyThread2.Terminate
else
ShowMessage('Thread not started');
end;

procedure TForm1.ThreadDone(var AMessage: TMessage); // keep track of when and which thread is done executing
begin
if ((MyThread1 <> nil) and (MyThread1.ThreadID = cardinal(AMessage.WParam))) then

begin
Thread1Active := false;
end;
if ((MyThread2 <> nil) and (MyThread2.ThreadID = cardinal(AMessage.WParam))) then
begin
Thread2Active := false;
end;
end;


procedure TForm1.FormCreate(Sender: TObject); // initialize to zero
begin
Thread1Active := false;
Thread2Active := false;
end;


procedure TForm1.TrackBar1Change(Sender: TObject); // set Thread 1 Priority

begin
if (MyThread1 <> nil) and (Thread1Active = true) then
MyThread1.priority := TThreadPriority(TrackBar1.Position);
end;

procedure TForm1.TrackBar2Change(Sender: TObject); // set Thread 2 Priority
begin
if (MyThread2 <> nil) and (Thread2Active = true) then
MyThread2.priority := TThreadPriority(TrackBar2.Position);
end;


procedure TForm1.FormDestroy(Sender: TObject); // Terminate any threads still running

begin
if (MyThread1 <> nil) and (Thread1Active = true) then
begin
MyThread1.Terminate;
MyThread1.WaitFor; // wait for it to terminate
end;
if (MyThread2 <> nil) and (Thread2Active = true) then
begin
MyThread2.Terminate;
MyThread2.WaitFor;
end;
end;

end.

object Form1: TForm1
Left = 516
Top = 256
Width = 712
Height = 507
Caption = 'TThread, TTrackBar, TProgressBar'
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'MS Sans Serif'
Font.Style = []
OldCreateOrder = False
Position = poDesktopCenter
OnCreate = FormCreate
OnDestroy = FormDestroy
PixelsPerInch = 96
TextHeight = 13
object Bevel1: TBevel
Left = 32
Top = 8
Width = 513
Height = 169
end
object Bevel2: TBevel
Left = 32
Top = 200
Width = 513
Height = 169
end
object Label1: TLabel
Left = 256
Top = 104
Width = 34
Height = 13
Caption = 'Priority:'
end
object Label2: TLabel
Left = 248
Top = 296
Width = 34
Height = 13
Caption = 'Priority:'
end
object ProgressBar1: TProgressBar
Left = 64
Top = 32
Width = 393
Height = 25
Min = 0
Max = 100
Step = 1
TabOrder = 0
end
object ProgressBar2: TProgressBar
Left = 64
Top = 224
Width = 401
Height = 25
Min = 0
Max = 100
TabOrder = 1
end
object Button1: TButton
Left = 72
Top = 80
Width = 105
Height = 25
Caption = 'Create Thread'
TabOrder = 2
OnClick = Button1Click
end
object Button2: TButton
Left = 72
Top = 272
Width = 105
Height = 25
Caption = 'Create Thread'
TabOrder = 3
OnClick = Button2Click
end
object TrackBar1: TTrackBar
Left = 296
Top = 104
Width = 193
Height = 33
Max = 6
Orientation = trHorizontal
Frequency = 1
Position = 3
SelEnd = 0
SelStart = 0
TabOrder = 4
TickMarks = tmBottomRight
TickStyle = tsAuto
OnChange = TrackBar1Change
end
object TrackBar2: TTrackBar
Left = 288
Top = 296
Width = 193
Height = 45
Max = 6
Orientation = trHorizontal
Frequency = 1
Position = 3
SelEnd = 0
SelStart = 0
TabOrder = 5
TickMarks = tmBottomRight
TickStyle = tsAuto
OnChange = TrackBar2Change
end
object Button3: TButton
Left = 72
Top = 128
Width = 105
Height = 25
Caption = 'Terminate Thread'
TabOrder = 6
OnClick = Button3Click
end
object Button4: TButton
Left = 72
Top = 320
Width = 105
Height = 25
Caption = 'Terminate Thread'
TabOrder = 7
OnClick = Button4Click
end
end

Saludos!

[marto]

Hola,

Trabajar con treads no es algo precisamente sencillo. En grupo albor (http://www.grupoalbor.com/) publican una revista llamada Sintesi sobre programación y en especial Deplhi muy recomendable (y gratuita) en español. No recuerdo qué números eran, pero se publicaron una serie de artículos sobre el uso de TThreads tanto sobre Windows como Linux muy interesantes

[shaktale]

Aqui (http://www.pergolesi.demon.co.uk/prog/threads/ToC.html) (Martin Harvey's web pages) tienes un tuturial sobre el tema.