ListBox -- Overview
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 Class Function

 ListBox()       Create a new ListBox object
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 Exported Instance Variables

 bitmap          The bitmap file to display on the button
 bottom          Numeric value indicating bottommost screen row
 buffer          Numeric value indicating position of item
 capCol          Numeric value indicating location of caption by column
 capRow          Numeric value indicating location of caption by row
 caption         Character string describing list box
 cargo           User-definable variable
 coldBox         Optional string specifying characters
 colorSpec       Character string indicating color
 dropDown        Optional logical value indicating a drop-down list
 fBlock          Code block evaluated at each input focus change
 hasFocus        Logical value indicating the input focus
 hotBox          Optional string specifying characters
 isOpen          Logical value indicating visibility of list
 itemCount       Numeric value total number of items
 left            Numeric value indicating leftmost screen column
 message         Character string describing the list box
 right           Numeric value indicating rightmost screen column
 sBlock          Code block evaluated at every state change
 top             Numeric value indicating topmost screen row
 topItem         Numeric value indicating position of first item
 typeOut         Logical value indicating list contents
 vScroll         Optional ScrollBar object whose orientation must be vertical
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 Exported Methods

 addItem()       Appends a new item to a list
 close()         Restores screen under drop-down list box
 delItem()       Removes item from a list
 display()       Shows a list box and its caption
 findText()      Determines the position of an item within a list
 getData()       Retrieves the data portion of a list box item
 getItem()       Retrieves a list box item
 getText()       Retrieves the text portion of a list box item
 hitTest()       Indicates position of mouse cursor relative to list box
 insItem()       Inserts a new item to a list
 killFocus()     Takes input focus away from the ListBox object
 nextItem()      Changes selected item to next one
 open()          Saves screen under drop-down list box
 prevItem()      Changes selected item to previous one
 scroll()        Indicates manner of scroll operation
 select()        Changes the selected item in a list
 setData()       Changes the data associated with a list item
 setFocus()      Gives input focus to the ListBox object
 setItem()       Replaces an item in a list
 setText()       Changes the text associated with a list item