Highlighting nodes in a JTree

Hi,
I'd like to know how I can produce the efect of highlighting nodes in a JTree when the mouse moves over the JTree.
Thanks

You say to get the mouseevent coordinates with a mouse
listener, but which component should be the caller of
the methos addMouseListener?
If I choose the jtree, I can't get the 'mouseevent
coordinates' each time the mouse moves over a node,
because the methods mouseEntered and mouseExited are
invoked just once (when the mouse enter inside the
jtree's area (mouseEntered), and when the mouse gets
out the jtree's area(mouseExited)), so I can't change
the boolean field to true for nodes which have the
mouse over.just use mouseMoved of the MouseMotionListener.
however, i have my doubts that you will have a lot of fun with the suggested method (correct though it is).
at least make sure you only call the repaint method if the mouse moved into a new node. you might want to try the the nodeChanged method, that way you don't repaint the whole tree every time.
thomas

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CTRL-click the node to de-select it.

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To control the appearance of tree nodes, you need to write a TreeCellRenderer. Check Sun's tutorial on how to use trees (there's a link to it in the API documentation for JTree). The signature of the method you need to implement is this:
public Component getTreeCellRendererComponent(
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Highlighting nodes in JTree

Hey guys please help me for this.
I want to generate a Tree. In which after some action a few nodes are selected.
Now i want to highlight those selected node in the Tree. Is it possible ??
Is anyone have any clue how to do that.
Thanks in advance

well, even I'm facing this issue in my application but i did a small workaround. I am sure there should be a better way of achieving this, which i hope someone will post in this thread.
Use Html tags in displaying the highlighted node:
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How do i expand all the nodes in a jtree

Hi,
I am working on a project where i need to expand all the nodes of a jtree i have tried a few different ways but it never seems to expand all the nodes..
I would be very greatful if someone could point me in the right direction
cheers
Mary

you could use the following method that expands nodes recursively
expandNode( myTree, myRootNode, new TreePath( myRootNode ) );
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thanks,

How many nodes does this tree have?
import java.awt.EventQueue;
import javax.swing.*;
import javax.swing.event.TreeModelListener;
import javax.swing.tree.*;
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}But for bounded tree model using DefaultMutableTreeNode look at bread/depth/preorder enumeration methods to walk the entire tree. Or look at the source code for those and adapt them to work with the TreeModel interface.

How to use custom nodes in a JTree without reinventing the wheel?

Hello,
Each node contains two JTextAreas in a Box layout and a few JButtons.
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Reading the tutorial, it seems I would have to reimplement the TreeModel, TreeCellRenderer/Editor, MutableTreeNode interfaces etc.
Can I use the DefaultTreeModel, and other standard widgets (great stuff!) to minimize the amount of reimplementation I must do. aka avoid reinventing the wheel? I was thinking of extending my node from the DefaultMutableTreeNode class - however it does not display the nodes with the TextAreas, buttons etc.
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thanks,
Anil

was able to fix it over here:
http://forum.java.sun.com/thread.jspa?messageID=4089777

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Don't use MouseListener.
Instead, make yourself a TreeSelectionListener as follows:
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myJTree.putClientProperty("JTree.lineStyle", "Horizontal");
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How can I get a count of ALL nodes in a JTree?

Not sure if I am missing something here or what. Is there an easy way to determine the total number of nodes in a JTree? I thought there would be a method to return this, but I'm not seeing it in JTree or DefaultTreeModel. Do I have to start at the root and recursively get child counts? Yuck!
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You are absolutely right! Create a recursive method and count all your children from the root.
Denis Krukovsky
http://dotuseful.sourceforge.net/

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I have created a JTree and want to dynamically change the color of some of the TreeNodes as my program runs. The JTree is displayed in a JPanel. There is an algorithm built into which identifies the nodes whose color I need to change. No user actions is performed (everythign is internal to the program).
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I think I was a bit too vague in my question. Let me try again...
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Hi everybody
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Hi,
i tried to used your code.
there is a problem, it is not taking the entire paths.
so if you have some children,it takes the paths only for the fathers.
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Okay, perhaps I am sidetracked today by all the sad craziness occuring in New York and DC, or perhaps I just don't have a grasp on JTrees yet...but...
I have implemented a TreeCellRender to create panels with buttons and other information to be the nodes of a JTree I created. Everything shows up beautifully, however, I want the buttons on this panel to depress and perfom actions (work like normal) when the user clicks/selects such a button in the tree structure. I can't figure out how to properly set up event handlers to get from the tree to the tree node to the "bean" I'm using as a node. If anyone has any helpful hints, I'd appreciate it!
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add actionlistener to the JTree, and then get the object by getLastPathComponent, and compare it if its the button and do the action.

Highlighting nodes in a JTree

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