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The Java Developers Almanac 1.4Order this book from Amazon. |
e1024. Finding a Node in a JTree Component// Create tree JTree tree = new JTree(); // Search forward from first visible row looking for any visible node // whose name starts with prefix. int startRow = 0; String prefix = "b"; TreePath path = tree.getNextMatch(prefix, startRow, Position.Bias.Forward); // Search backward from last visible row looking for any visible node // whose name starts with prefix. startRow = tree.getRowCount()-1; prefix = "b"; path = tree.getNextMatch(prefix, startRow, Position.Bias.Backward); // Find the path (regardless of visibility) that matches the // specified sequence of names path = findByName(tree, new String[]{"JTree", "food", "bananas"}); // Finds the path in tree as specified by the node array. The node array is a sequence // of nodes where nodes[0] is the root and nodes[i] is a child of nodes[i-1]. // Comparison is done using Object.equals(). Returns null if not found. public TreePath find(JTree tree, Object[] nodes) { TreeNode root = (TreeNode)tree.getModel().getRoot(); return find2(tree, new TreePath(root), nodes, 0, false); } // Finds the path in tree as specified by the array of names. The names array is a // sequence of names where names[0] is the root and names[i] is a child of names[i-1]. // Comparison is done using String.equals(). Returns null if not found. public TreePath findByName(JTree tree, String[] names) { TreeNode root = (TreeNode)tree.getModel().getRoot(); return find2(tree, new TreePath(root), names, 0, true); } private TreePath find2(JTree tree, TreePath parent, Object[] nodes, int depth, boolean byName) { TreeNode node = (TreeNode)parent.getLastPathComponent(); Object o = node; // If by name, convert node to a string if (byName) { o = o.toString(); } // If equal, go down the branch if (o.equals(nodes[depth])) { // If at end, return match if (depth == nodes.length-1) { return parent; } // Traverse children if (node.getChildCount() >= 0) { for (Enumeration e=node.children(); e.hasMoreElements(); ) { TreeNode n = (TreeNode)e.nextElement(); TreePath path = parent.pathByAddingChild(n); TreePath result = find2(tree, path, nodes, depth+1, byName); // Found a match if (result != null) { return result; } } } } // No match at this branch return null; }
e1025. Adding a Node to a JTree Component e1026. Removing a Node to a JTree Component e1027. Converting a Node in a JTree Component to a TreePath e1028. Converting All Nodes in a JTree Component to a TreePath Array
© 2002 Addison-Wesley. |