ListBox Class (Typed)

Object
  VObject
    Control
      TextControl
        BaseListBox
          ListBox
            ComboBox

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List boxes and combo boxes display a list of items or choices to the user. The list box methods will allow you to add, arrange, remove, and interrogate the list of items. When one of the items is selected, ListBox:CurrentItem, ListBox:CurrentItemNo, ListBox:TextValue, and ListBox:Value are updated. Either a one-dimensional or two-dimensional array is specified in the FillUsing() method, with a row for each of the items available for selection. With a two-dimensional array, the first element is called the display value, and the second element is called the return value. When an item is selected, ListBox:TextValue contains the first element (the display value), and ListBox:Value contains the second element (the return value). If no item is selected, ListBox:TextValue is NULL_STRING and ListBox:Value is NIL. A list box may be bound to a field (character, date, logical, numeric, or memo) in a server. The field's data value is stored in ListBox:Value. The list box compares the data value to the second element values specified in the FillUsing() array, and if a match is found, the first element (the display value) is stored in ListBox:TextValue. In a "no-match" situation, the list box shows no item selected, ListBox:CurrentItem is NULL_STRING, ListBox:CurrentItemNo is set to 0, and ListBox:TextValue and ListBox:Value reflect the field contents. If an item is selected, ListBox:CurrentItemNo is set to a number between 1 and ListBox:ItemCount, and the corresponding second element is stored as ListBox:Value and as the field's data value. You can also create a multiple selection list box, which allows you to manage multiple items within a list box. Any number of items in a list box can be selected together (referred to as multiple selection). Each item is toggled on/off each time the user clicks on it. A multiple selection list box is created by selecting the LBOXMULTIPLESEL style when creating a ListBox object. Certain properties and methods of this class apply specifically to multiple selection list boxes, including SelectedCount access, ChangeSelected(), ClearSelection(), DeselectItem(), FirstSelected(), NextSelected(), and SelectItem().

This example creates and fills a list box with a list of animals: A X# list box is equivalent to a Windows list box with the LBS_NOTIFY and LBS_SORT styles. List boxes are normally specified in the resource entity like this: