ProvideX V8.20 > Language Reference > 2. Directives

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Format 1: Define/Create List Box

LIST_BOX ctl_id,@(col,ln,wth,ht)[,ctrlopt]

Use this format to define or create a list box and give it a unique identifier in ctl_id.

When a user selects an item from a list box, the item's associated ctl_id is used in

generating a CTL value. Use an integer or numeric expression between -32000 and

+32000 for the ctl_id. The standard list box format lists a single element of data in a

single column format. Depending on the implementation, list box appearance and

format type may be changed using the following control options:

FNT= sets the font for the list box. If you omit this option, ProvideX uses the system

default font. Use FNT="*" asterisk to set the font to the standard text-mode fixed font.

OPT= expands the definition. See LIST_BOX OPT= Settings, p.178.

Note: Some of the settings (including OPT="r", OPT="l", and OPT="e") are used

specifically for the creation of List View, Tree View list boxes.

FMT= defines various attributes, including column/row sizing, titles and images

depending on list box requirements. For more elaborate list box styles, see

Formatted, p.186, List View, p.188, Report View, p.188, or Tree View, p.191.

The example below creates a standard list box that generates a CTL=100 when an

item is selected from it and uses FNT=text mode fixed font. The list box is loaded with

the items Dog, Cat, and Pig. The programmer writes Cat as the initial/highlighted

selection and removes Dog from the top of the list.

0010

PRINT 'CS'; LIST

0020

LIST_BOX 100,@(2,14,12,6),FNT="*"

0030

LIST_BOX LOAD 100,"Dog/Cat/Pig/"; WAIT 1

0040

LIST_BOX WRITE 100,"Cat"; WAIT 1

0050

LIST_BOX LOAD 100,1,*; WAIT 1

0060

END

Note: The LIST_BOX formats described below apply to all list box types.

Format 2: Remove

LIST_BOX REMOVE ctl_id[,ERR=stmtref]

Use the LIST_BOX REMOVE format to delete a list box. (To delete an individual

element, use the LIST_BOX LOAD directive instead.)

Format 3: Disable/Enable

LIST_BOX {DISABLE | ENABLE} ctl_id[,ERR=stmtref]

Use the LIST_BOX DISABLE format to gray out a list box so that it will be visible but

inaccessible to users. To reactivate it, use LIST_BOX ENABLE.