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POJTree getCellRenderderComponet refers to a removed child
 

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  1. POJTree getCellRenderderComponet refers to a removed child
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    <p>I have a JTree with a custom TreeCellRenderer.</p> <pre><code> DefaultMutableTreeNode myTreeRoot = new DefaultMutableTreeNode(); JTree myTree = new JTree(myTreeRoot); myTree.setCellRenderer(new DefaultTreeCellRenderer() { @Override public Component getTreeCellRendererComponent(JTree tree, Object value, boolean sel, boolean expanded, boolean leaf, int row, boolean hasFocus) { if (((DefaultMutableTreeNode) value).getUserObject() instanceof MyObject) { System.out.println("============= my object ===========" + value); } return super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf, row, hasFocus); } }); </code></pre> <p>Then I add the nodes to the tree dynamically after it displayed. Consider the case of adding only one child.</p> <pre><code> MyObject object = new MyObject("Child Node"); DefaultMutableTreeNode myTreeNode = new DefaultMutableTreeNode(object); myTreeRoot.add(myTreeNode); </code></pre> <p>Then I hide tree root as well</p> <pre><code> myTree.expandRow(0); myTree.setRootVisible(false); myTree.setShowsRootHandles(true); if (myTreeRoot.getChildCount() != 0) { myTree.setSelectionRow(0); } SwingUtilities.invokeLater(new Runnable() { public void run() { devicesTree.updateUI(); } }); </code></pre> <p>Laterly there is another option to remove these nodes</p> <pre><code> private void removeNode(MyObject object) { DefaultMutableTreeNode myTreeNode = getTreeeNode(object); //This method traverse through the tree and returns the corresponding node DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode) myTree.getSelectionPath().getLastPathComponent(); int selectedRow = -1; if (myTree.getSelectionRows().length &gt; 0) { selectedRow = myTree.getSelectionRows()[0]; } boolean isSelected = selectedNode == myTreeNode; if (isSelected) { if (myTree.getRowCount() == 1) { myTree.clearSelection(); } else if (myTree.getRowCount() &gt; selectedRow + 1) { myTree.setSelectionRow(selectedRow + 1); } else if (selectedRow != 0) { myTree.setSelectionRow(0); } } DefaultMutableTreeNode parent = (DefaultMutableTreeNode) myTreeNode.getParent(); parent.remove(myTreeNode); SwingUtilities.invokeLater(new Runnable() { public void run() { myTree.updateUI(); } }); } </code></pre> <p>Now the problem I have is when there is only one child at the root of the tree and if I chosen to remove that child, after the removal getTreeCellRendererComponent() method still points to that removed object. Is there any clue for that?</p>
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