Q127942: How to Place a Timer in the Main Window

Article: Q127942
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): kbcode
Last Modified: 12-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SUMMARY
=======

The Timer control is new to Visual FoxPro. It can execute code at regular
intervals and is not a visual control. You can use the timer to periodically
execute a set of commands. The following two sample programs illustrate the
basic commands to place a timer on the Visual FoxPro version 3.0 desktop.

MORE INFORMATION
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Method One: Use the ADDOBJECT() Method to Place the Timer on the Desktop
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The _SCREEN system memory variable holds a reference to the main Visual FoxPro
window. It allows you to manipulate it as a form. This memory variable will be
used in this sample.

The following code places a timer that displays the time. Similar code can be
used to place any control on the desktop. Press the F6 key to release the
timer.

Place the following code in a program (.PRG) file:

     * To remove the object:
     ON KEY LABEL F6 _SCREEN.RemoveObject('oTime')

     * To activate the Timer:
     _SCREEN.AddObject('oTime','MyTimer')

     * Class definition. The TIMER event is triggered every second, and a
     * WAIT WINDOW is displayed.
     DEFINE CLASS MyTimer AS Timer
        Interval= 1000
        PROCEDURE Timer
          WAIT WINDOW (TIME()) NOWAIT
        ENDPROC
     ENDDEFINE

Method two: Encapsulate the Object in a Container Class
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This sample program does the same operations as the first example. The timer is
added to a container class, and the CREATEOBJECT() function instantiates the
object. To execute the sample, place it in a .PRG file and run the program.
Press the F6 key to release the timer.

     PUBLIC oTimerObj

     * The instance variable is released when F6 is pressed.
     ON KEY LABEL f6 RELEASE oTimerObj

     oTimerObj=CREATEOBJECT('MyTimer')

     DEFINE CLASS MyTimer as Container
        ADD OBJECT oTimerobj as TimerClock
     ENDDEFINE

     DEFINE CLASS TimerClock as Timer
        Interval = 1000
        PROCEDURE Timer
           WAIT WINDOW (TIME()) NOWAIT
        ENDPROC
     ENDDEFINE

Additional query words: VFoxWin

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Keywords          : kbcode 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0

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