How to make one shot timer function in Delphi (like setTimeout in JavaScript)?

Question

The setTimeout is helpful in JavaScript language. How would you create this function in delphi ?

SetTimeOut(procedure (Sender: TObject);
begin
  Self.Counter         


        

Answer 1

Something like

type
TMyProc = Procedure of Object(Sender: TObject);

TMyClass = Object
    HandlerList = TStringList;
    TimerList = TStringlist;

  Procedure CallThisFunction(Sender :TObject); 

  function setTimeout(Timeout: Integer; ProcToCall : TMyProc)

end;






function setTimeout(Timeout: Integer; ProcToCall : TMyProc)
var
  Timer : TTimer;
begin

  Timer := TTimer.Create(nil);
  Timer.OnTimer := CallOnTimer;
  Timer.Interval := Timeout;
  Timer.Enabled := true;
  HandlerList.AddObject(ProcToCall);
  TimerList.AddObject(ProcToCall);

end;


function CallOnTimer(Sender : TObject)
var TimerIndex : Integer;
    HandlerToCall : TMyProc;
    Timer : TTimer;
begin

TimerIndex :=   TimerList.IndexOfObject(Sender);
HandlerToCall := (HandlerList.Objects[TimerIndex] as TMyProc) ;

HandlerToCall(Self);

HandlerList.Delete(TimerIndex);
Timer := (TimerList.Objects(TimerIndex) as TTimer);
Timer.Free;
TimerList.Delete(TimerIndex);


end;

This has just been hacked together and not tested in any way but shows the concept. Basically build a list of the timers and procedures you want to call. As it is the self object is passed to the procedure when it is called but you could build a third list that contained the object to be used as a parameter in the call to setTimeout.

The Objects are then cleaned up by freeing after the method has been called.

Not quite the same as javascripts setTimeout but a delphi approximation.

ps. I haven't really moved on from Delphi7 so if there is a new fangled way of doing this in Delphi XE I don't know about it.