| Use the OptionsTitle class to add a Title to a list or
array of Options. The label text will be rendered marked by dashes.
Use this class instead of OptionTitle to indicate that no items have
been selected from this list. This is important in cases where a list
component like a DropDown or Listbox, may be bound to a null initial
component value.
When these components are bound to a null value, especialy a DropDown
where a value will always be submitted, it is not possible to
detect without a special Option that no change has actually occurred
and a user didn't explicitly select an option. This can
result in an incorrect value change event and model update.
When an OptionTitle is the first option in an array or
list of Option's assigned to the "items" property of a
DropDown, OptionTitle's value will be submitted when the form
is submitted, if a different option is not chosen by the user. When the
submitted value is decoded, this value will be identified and will treat the
submission of the DropDown as if it was not submitted.
This prevents a false update in the case where a user had not made
any change at all and the initial value of the DropDown does not
match the submitted value, such is the case when the initial value
of the component is null.
OptionTitle is also useful for a Listbox where once an
an item is selected it cannot be deselected. Using OptionTitle
gives the user an opportunity to select it, thereby deselecting a
previous selection. On form submit the list will appear as if nothing
had been selected.
NOTE: Calling setValue on this class will not change its
value. The label can be set.
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