CODEWITHSUNDEEP
javaswingjtree
ibrahimyilmaz
ibrahimyilmaz

Reputation: 18909

How to update JTree elements

I use JTree with TreeNode which extending DefaultMutableTreeNode.when I add new node,i cant update JTree.Any help will be appreciated

Upvotes: 1

Views: 17058

Answers (5)

Gnoupi
Gnoupi

Reputation: 4734

Adding to the node only is not enough, the Tree needs to be notified. The correct way to do this is to let the model take care of adding/removing nodes, as it will notify correctly the Tree on the way.

In case of a DefaultTreeModel (which should be the one used in the JTree if you haven't made your own TreeModel), you have the method insertNodeInto(MutableTreeNode newChild, MutableTreeNode parent, int index), which you can use.

Upvotes: 5

NullPumpkinException
NullPumpkinException

Reputation: 1475

if you use DefaultTreeModel try to call its reload() method.

DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
model.reload();

//or... model.reload(nodeUpdatedByYou);

Never use tree.updateUI() as this is a look and feel operation (although it works).

Upvotes: 7

Sergey
Sergey

Reputation: 1038

Actually, it is enough to reload the parent node. Internally,

public void reload()

is using 

public void reload(TreeNode node)

but with root as its parameter, so, unless you are updating the direct root's leaf, you are better of using a more fine-grained version.

Upvotes: 6

Summer_More_More_Tea
Summer_More_More_Tea

Reputation: 13356

Since Java use MVC to implement JTree component, your operation that add a node just change the model. Besides, you should notify representation of the tree some modifications have taken place. Try use fireTreeNodes*** methods of your tree model to notify the JTree object this kind of modification. Refer Java API for details. Good luck.

Upvotes: 3

ring bearer
ring bearer

Reputation: 20783

Are you using DefaultTreeModel?

If so, when adding use insertNodeInto API so that appropriate events are generated.

Upvotes: 1

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