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version 2004.1 (Modified)
Get listbox information ({*; }object; info) 
Longint
| Parameter | Type | Description | |
| * | | If specified, object is an object name (string) | |
| If omitted, object is a variable | |||
| object | Form object | | Object name (if * is specified) or |
| Variable (if * is omitted) | |||
| info | Longint | | Information to get |
| Function result | Longint |  | Current value |
Description
The Get listbox information command returns various information regarding the current visibility and size of headers and scrollbars in the list box object set using the object and * parameters.
If you pass the optional * parameter, you indicate that the object parameter is an object name (string). If you do not pass this parameter, you indicate that the object parameter is a variable. In this case, you do not pass a string, but a variable reference. For more information about object names, refer to the Object Properties section.
In the dans info parameter, pass a value indicating the type of information that you want to get. You can use a value or one of the following constants from the "List box" theme:
| Constant | Type | Value | Returned value(s) |
| Display listbox header | Longint | 0 | 0=hidden, 1=shown |
| Listbox header height | Longint | 1 | Height in pixels |
| Display listbox hor scrollbar | Longint | 2 | 0=hidden, 1=shown |
| Listbox hor scrollbar height | Longint | 3 | Height in pixels |
| Display listbox ver scrollbar | Longint | 4 | 0=hidden, 1=shown |
| Listbox ver scrollbar width | Longint | 5 | Width in pixels |
| Position listbox hor scrollbar | Longint | 6 | Position of the cursor in pixels |
| Position listbox ver scrollbar | Longint | 7 | Position of the cursor in pixels |
• The first six constants are useful for calculating the actual size of a list box area in a form.
• When you use the constants Position listbox hor scrollbar or Position listbox ver scrollbar, the Get listbox information command returns the position of the scrolling cursor in relation to its original position, i.e. the size of the hidden part of the window, expressed in pixels. By default, this position corresponds to 0. Combined, for example, with information concerning the row height, this value lets you find out the contents displayed in the listbox.
Example
Given a list box containing rows with a height of 20 pixels each. You execute the following statement:
$scroll:=Get listbox information(*;"Listbox";Position listbox ver scrollbar)
If, for instance, $scroll returns 200, you can conclude that the 11th row is currently the first one displayed in the list box (200/20=10, thus 10 rows are hidden).
See Also
SET SCROLLBAR VISIBLE, SHOW LISTBOX GRID.
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