Used to create an event when nodes have been changed, inserted, or
removed, identifying the path to the parent of the modified items as
an array of Objects.
Used to create an event when nodes have been changed, inserted, or
removed, identifying the path to the parent of the modified items as
an array of Objects. All of the modified objects are siblings which are
direct descendents (not grandchildren) of the specified parent.
The positions at which the inserts, deletes, or changes occurred are
specified by an array of
int. The indexes in that array
must be in order, from lowest to highest.
For changes, the indexes in the model correspond exactly to the indexes
of items currently displayed in the UI. As a result, it is not really
critical if the indexes are not in their exact order. But after multiple
inserts or deletes, the items currently in the UI no longer correspond
to the items in the model. It is therefore critical to specify the
indexes properly for inserts and deletes.
For inserts, the indexes represent the final state of the tree,
after the inserts have occurred. Since the indexes must be specified in
order, the most natural processing methodology is to do the inserts
starting at the lowest index and working towards the highest. Accumulate
a Vector of Integer objects that specify the
insert-locations as you go, then convert the Vector to an
array of int to create the event. When the postition-index
equals zero, the node is inserted at the beginning of the list. When the
position index equals the size of the list, the node is "inserted" at
(appended to) the end of the list.
For deletes, the indexes represent the initial state of the tree,
before the deletes have occurred. Since the indexes must be specified in
order, the most natural processing methodology is to use a delete-counter.
Start by initializing the counter to zero and start work through the
list from lowest to higest. Every time you do a delete, add the current
value of the delete-counter to the index-position where the delete occurred,
and append the result to a Vector of delete-locations, using
addElement(). Then increment the delete-counter. The index
positions stored in the Vector therefore reflect the effects of all previous
deletes, so they represent each object's position in the initial tree.
(You could also start at the highest index and working back towards the
lowest, accumulating a Vector of delete-locations as you go using the
insertElementAt(Integer, 0).) However you produce the Vector
of initial-positions, you then need to convert the Vector of Integer
objects to an array of int to create the event.
Notes:
- Like the
insertNodeInto method in the
DefaultTreeModel class, insertElementAt
appends to the Vector when the index matches the size
of the vector. So you can use insertElementAt(Integer, 0)
even when the vector is empty.
To create a node changed event for the root node, specify the parent
and the child indices as null.
Parameters:
- source - the Object responsible for generating the event (typically
the creator of the event object passes this
for its value)
- path - an array of Object identifying the path to the
parent of the modified item(s), where the first element
of the array is the Object stored at the root node and
the last element is the Object stored at the parent node
- childIndices - an array of int that specifies the
index values of the removed items. The indices must be
in sorted order, from lowest to highest
- children - an array of Object containing the inserted, removed, or
changed objects
See Also:
TreePath,
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