JTree problem (0/1)

[Vincent H]

Hi,

For a project I'm working on I'm building a GUI that uses a JTree. This tree represents groups of hardware. Each node
represents such a piece of hardware. The name that is presented by the node is either the ip-address or the name of the
system and possilby a different color when the system is on-line. To be able to do that I'm using my own
TreeCellRenderer. The grouping of systems is handled by a TreeModel I made.

Now when I detect that a system becomes on-line, I update the model and trigger the TreeModelListeners'
treeNodeChanged() methods. I can see the tree change but when the string presented is longer that the initial string it
is truncated (ellipses are shown). I can't figure out what I'm doing wrong here.

To actually show what I'm experiencing I've made a small demo app that presents the problem. The classes are attached.
On the GUI press the "Hit Me!" button to make a different team become the champion (yeah I had to find some kind of
example). To see the problem you have to expand all nodes before hitting the button.

Has anyone experienced this? Any suggestions how to resolve this elegantly?

Thanks!

Vincent Hartsteen

 

[Jim Sculley]

Hi,

For a project I'm working on I'm building a GUI that uses a JTree. This tree represents groups of hardware. Each node
represents such a piece of hardware. The name that is presented by the node is either the ip-address or the name of the
system and possilby a different color when the system is on-line. To be able to do that I'm using my own
TreeCellRenderer. The grouping of systems is handled by a TreeModel I made.

Now when I detect that a system becomes on-line, I update the model and trigger the TreeModelListeners'
treeNodeChanged() methods. I can see the tree change but when the string presented is longer that the initial string it
is truncated (ellipses are shown). I can't figure out what I'm doing wrong here.

To actually show what I'm experiencing I've made a small demo app that presents the problem. The classes are attached.
On the GUI press the "Hit Me!" button to make a different team become the champion (yeah I had to find some kind of
example). To see the problem you have to expand all nodes before hitting the button.

Has anyone experienced this? Any suggestions how to resolve this elegantly?

See

http://forum.java.sun.com/thread.jspa?forumID=57&threadID=147624

Jim S.

 

[jonck]

Actually I've experienced this just recently. I found out that to solve
this, instead of creating a two-argument TreeModelEvent(Object sourc,
TreePath path), you need to create a 4-argument TreeModelEvent(Object
source, TreePath path, int[] childIndices, Object[] children).
Note that the second argument here differs depending on which
fireTreeNodeXXX method you're going to call. When calling the
fireTreeNodesInserted or fireTreeNodesRemoved method, the path argument
should be a path leading to the parent. When you want to call the
fireTreeNodesChanged method the path argument should be a path leading
to the child.

Regards, Jonck

 

[Vincent H]

Actually I've experienced this just recently. I found out that to solve
this, instead of creating a two-argument TreeModelEvent(Object sourc,
TreePath path), you need to create a 4-argument TreeModelEvent(Object
source, TreePath path, int[] childIndices, Object[] children).
Note that the second argument here differs depending on which
fireTreeNodeXXX method you're going to call. When calling the
fireTreeNodesInserted or fireTreeNodesRemoved method, the path argument
should be a path leading to the parent. When you want to call the
fireTreeNodesChanged method the path argument should be a path leading
to the child.

Regards, Jonck

Thanks! This actually works for me. The other solution suggested in this thread makes sense to me as well. However it
did not seem to work. Using the 4 arg constructor of the TreeModelEvent works like a charm though. In hindsight the
javadoc makes sense as well.

Thanks for your input.

Vincent