TTimer.Interval Property

Determines the amount of time, in milliseconds, that passes before the timer component initiates another OnTimer event.

Pascal

property Interval: Cardinal;

C++

__property unsigned Interval;

Description

Interval determines how frequently the OnTimer event occurs. Each time the specified interval passes, the OnTimer event occurs.

Use Interval to specify any cardinal value as the interval between OnTimer events. The default value is 1000 (one second).

Note: A 0 value is valid, however the timer will not call an OnTimer event for a value of 0.

C++ Examples:

Copy Code

/*
Place a TTimer object in the form and enter Timer1Timer in 
the OnTimer event.  Place other controls in the form and 
change the active control at runtime.  The following event 
handler responds to timer events by moving the active control
one pixel to the right every 100 miliseconds:
*/
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
  Timer1->Interval = 100;
  if (ActiveControl)
    ActiveControl->Left = ActiveControl->Left + 1;
}

Copy Code

/*
This code uses a button, a timer and a maskedit on a
form. When the user clicks the button, the form
disappears for the period of time specified in the
Interval property of the timer control, then the form
reappears:
*/
void __fastcall TForm1::Button1Click(TObject *Sender)
{
  Timer1->Interval = StrToInt(MaskEdit1->Text);
  Timer1->Enabled = true;
  Hide();
}

void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
  Visible = true;
  Timer1->Enabled = false;
}

Copy Code

/*
This example uses a timer on a form. When the application
runs and the user minimizes the application, the timer
starts and the application returns to its normal size when
an OnTimer event occurs.  The timer then shuts down until
the next time the form is minimized.  Be sure to declare the
AppStartTimer method as a public method of TForm1.  Place a
TTimer object in the form and enter Timer1Timer in the OnTimer
event.
*/
void __fastcall TForm1::FormCreate(TObject *Sender)
{
  Application->OnMinimize = AppStartTimer;
  Timer1->Interval = 1000;
}

void __fastcall TForm1::AppStartTimer(TObject *Sender)
{
  Timer1->Enabled = true;
}

//---------------------------------------------------------------------------
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
  Application->Restore();
  Timer1->Enabled = false;
}

Delphi Examples:

Copy Code

{
Place a TTimer object in the form and enter Timer1Timer in 
the OnTimer event.  Place other controls in the form and 
change the active control at runtime.  The following event 
handler responds to timer events by moving the active control
one pixel to the right every 100 miliseconds:
} 
procedure TForm1.Timer1Timer(Sender: TObject);
begin
  Timer1.Interval := 100;
  if ActiveControl <> nil then
    ActiveControl.Left := ActiveControl.Left + 1;
end;

Copy Code

{
This code uses a button, a timer and a maskedit on a
form. When the user clicks the button, the form
disappears for the period of time specified in the
Interval property of the timer control, then the form
reappears:
}
procedure TForm1.Button1Click(Sender: TObject);
begin
  Timer1.Interval := StrtoInt(MaskEdit1.Text);
  Timer1.Enabled := True;
  Hide;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  Visible := True;
  Timer1.Enabled := False;
end;

Copy Code

{
This example uses a timer on a form. When the application
runs and the user minimizes the application, the timer
starts and the application returns to its normal size when
an OnTimer event occurs.  The timer then shuts down until
the next time the form is minimized.  Be sure to declare the
AppStartTimer method as a public method of TForm1.  Place a
TTimer object in the form and enter Timer1Timer in the OnTimer
event.
}
procedure TForm1.FormCreate(Sender: TObject);
begin
  Application.OnMinimize := AppStartTimer;
end;

procedure TForm1.AppStartTimer(Sender: TObject);
begin
  Timer1.Enabled := True;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  Application.Restore;
  Timer1.Enabled := False;
end;