Q238513: PRB: Opening a ComboBox Prevents Timer Event Code from Executing
Article: Q238513
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a,6.0
Operating System(s):
Keyword(s): kbContainer kbCtrl kbvfp500 kbvfp500a kbvfp600 kbGrpDSFox kbDSupport
Last Modified: 13-AUG-1999
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The information in this article applies to:
- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0
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SYMPTOMS
========
Event code in a timer object is not executed at the interval specified in the
timer object's Interval property.
CAUSE
=====
This behavior occurs when the timer interval of the timer object is set to an
extremely low value.
RESOLUTION
==========
Set the timer object's Interval property to a higher value.
MORE INFORMATION
================
Steps to Reproduce Behavior
---------------------------
1. Create a program file named Timedemo.prg using the following code:
PUBLIC xForm
xForm=CREATEOBJECT("TimerForm")
xForm.SHOW()
DEFINE CLASS TimerForm AS FORM
ncount=0
starttime=TIME()
ADD OBJECT Combo1 AS COMBOBOX WITH;
STYLE=2,;
FONTSIZE=8,;
HEIGHT=22,;
BOUNDTO=.T.,;
ROWSOURCETYPE=5
ADD OBJECT TextBox1 AS TEXTBOX WITH;
TOP=0,;
LEFT=150
ADD OBJECT Timer1 AS TIMER WITH;
INTERVAL=1,;
ENABLED=.T.
DIMENSION aArray(1)
ncount=0
PROCEDURE INIT
LOCAL tmpi,tmpnlen
tmpnlen=100
FOR tmpi=1 TO tmpnlen
DIMENSION THIS.aArray(tmpi)
THIS.aArray(tmpi)=tmpi
ENDFOR
THIS.Combo1.ROWSOURCE="thisform.aArray"
THIS.Combo1.REQUERY()
THIS.Combo1.LISTINDEX=1
THIS.Combo1.LEFT=5
THIS.starttime=TIME()
ENDPROC
PROCEDURE Timer1.TIMER
THISFORM.ncount=THISFORM.ncount+1
IF THISFORM.ncount=5*(1000/THISFORM.Timer1.INTERVAL)
THISFORM.CALCTIME()
THISFORM.ncount=0
THISFORM.starttime=TIME()
ENDIF
ENDPROC
PROCEDURE calctime
started=THISFORM.starttime
stoptime=TIME()
current_space=SELECT()
rec_count=RECCOUNT()
SELECT 0
IF LEN(ALLTRIM(started))=20
startda=VAL(LEFT(started,2))
STARTMO=VAL(SUBSTR(started,4,2))
startyr=VAL(SUBSTR(started,7,2))
IF UPPER(RIGHT(started,2))="PM"
starthr=VAL(SUBSTR(started,10,2))+12
ELSE
starthr=VAL(SUBSTR(started,10,2))
ENDIF
startmin=VAL(SUBSTR(started,13,2))
startsec=VAL(SUBSTR(started,16,2))
ELSE
starthr=VAL(LEFT(started,2))
startmin=VAL(SUBSTR(started,4,2))
startsec=VAL(RIGHT(started,2))
ENDIF
IF LEN(ALLTRIM(stoptime))>8
stopda=VAL(LEFT(stoptime,2))
stopmo=VAL(SUBSTR(stoptime,4,2))
stopyr=VAL(SUBSTR(stoptime,7,2))
IF UPPER(RIGHT(stoptime,2))="PM"
stophr=VAL(SUBSTR(stoptime,10,2))+12
ELSE
stophr=VAL(SUBSTR(stoptime,10,2))
ENDIF
stopmin=VAL(SUBSTR(stoptime,13,2))
stopsec=VAL(SUBSTR(stoptime,16,2))
ELSE
stophr=VAL(LEFT(stoptime,2))
stopmin=VAL(SUBSTR(stoptime,4,2))
stopsec=VAL(RIGHT(stoptime,2))
ENDIF
IF startsec>stopsec
stopsec=stopsec+60
stopmin=stopmin-1
ENDIF
IF startmin>stopmin
stopmin=stopmin+60
stophr=stophr-1
ENDIF
elapsedtime=REPLICATE("0",2-LEN(ALLTRIM(STR(stophr-starthr)))) + ;
ALLTRIM(STR(stophr-starthr)) + ":" + ;
REPLICATE("0",2-LEN(ALLTRIM(STR(stopmin-startmin)))) + ;
ALLTRIM(STR(stopmin-startmin)) + ":" + ;
REPLICATE("0",2-LEN(ALLTRIM(STR(stopsec-startsec)))) + ;
ALLTRIM(STR(stopsec-startsec))
IF !FILE('TIMETRAP.DBF')
CREATE TABLE timetrap (elapsed c(8), tinterval i)
ENDIF
INSERT INTO timetrap ;
VALUES (elapsedtime, THISFORM.Timer1.INTERVAL)
USE
SELECT (current_space)
THISFORM.TextBox1.VALUE=elapsedtime
THISFORM.TextBox1.REFRESH
ENDPROC
ENDDEFINE
2. From the Command window, type:
"DO Timedemo" (without the quotation marks)
3. Observe that the value "00:00:05" appears in the text box after approximately
five seconds.
4. Click the combobox, move the mouse pointer down the center of the combobox
and position the mouse pointer over the number 7.
5. Hold the mouse pointer over the number 7 for approximately 45 seconds.
6. Move the mouse away from the combobox and click on the form. Note the value
displayed in the text box. The value is something other than 00:00:05. This
value is greater than five seconds. The value may appear in the text box
before you actually click on the form.
(c) Microsoft Corporation 1999, All Rights Reserved. Contributions by John Desch,
Microsoft Corporation.
Additional query words:
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Keywords : kbContainer kbCtrl kbvfp500 kbvfp500a kbvfp600 kbGrpDSFox kbDSupport
Technology : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600 kbVFP500a
Version : WINDOWS:5.0,5.0a,6.0
Issue type : kbprb
Solution Type : kbpending
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