Columns can be sorted in ascending or
descending order, interactively or by programming.
Interactively, the user clicks a column
header once to sort it in ascending order, twice to sort it in
descending order, and three times for no sorting at all. Using the
Shift key while clicking the column header adds this column as a
sorting criterion, whereas otherwise the column is set as the only
sorting criterion.
By programming, you can use the following
methods:
addSortingCriteriaaddSortingCriteria adds
the given attribute as a sorting criterion. This method takes as
its arguments:
the
attribute corresponding to the column to be sorted
an
order
parameter that defines the position of the column among the
sorting criteria
the
ascendingOrder
parameter, which, when set to
true
, sorts the column in ascending order
the parameter
useDisplayValue
, which indicates whether the sorting is applied to the
display values (that is, with style sheets applied) or to the
raw values
Each sorted column serves as a sorting criterion. If
order
equals
1
, the column is selected as the first sorting criterion, if
it equals
2
, it is selected as the second sorting criterion, and so on.
If
order
is less than
1
, the column is considered as the first criterion. If
order
is greater than the current number of criteria, the column is
considered as the next criterion.
getSortingOrder returns the position as a
sorting criterion of the specified attribute.