ProvideX V8.20 > Language Reference > 2. Directives

100

Format 15: Clear Current Selection

DROP_BOX WRITE ctl_id,"" [,ERR=stmtref]

Use this format to clear the currently selected entry in drop boxes.

Note: This behavior can be altered by use of the '+N' & '-N' Mnemonics, p.621.

Format 16: Report All Changes

DROP_BOX AUTO ctl_id[,ERR=stmtref]

Use the DROP_BOX AUTO format to have ProvideX generate a CTL value to report

all changes whenever the user highlights an element from a drop box list.

Example

0010

! DROP_BOX Creation and Use

0020

PRINT 'CS'; LIST

0030

DROP_BOX 88,@(30,18,15,10)

0040

DROP_BOX LOAD 88,"CAT,DOG,PIG,FOX,"

0050

DROP_BOX WRITE 88,"CAT"

0060

LET D_BX=88

0070

SETCTL D_BX:READ_BOX

0080

DROP_BOX GOTO D_BX

0090

PRINT @(30,24),"Try Mouse and/or keyboard to select. END=<F4>"

0100

OBTAIN (0,SIZ=1,ERR=0100)@(0,0),'CURSOR'("off"),'ME',IN_VAR$,'MN'

0110

LET CT=CTL; IF CT=4 THEN GOTO END

0120

READ_BOX:

0130

DROP_BOX READ D_BX,ANIMAL$,STROKE$,ERR=0001

0140

DROP_BOX READ D_BX,IND_NUM

0150

PRINT @(30,20),"HTA(SELECTION) : ",HTA(STROKE$)," AND CTL=",CTL:"#####"

0160

PRINT @(30,21),"Index for ",ANIMAL$,@(44,21)," : ",IND_NUM,""

0170

GOTO 0100

0180

END:

0190

DROP_BOX REMOVE D_BX

0200

PRINT 'CS'