src/be/nikiroo/fanfix_swing/gui/utils/TreeSnapshot.java

   1 package be.nikiroo.fanfix_swing.gui.utils;
   2
   3 import java.util.ArrayList;
   4 import java.util.LinkedList;
   5 import java.util.List;
   6
   7 import javax.swing.JTree;
   8 import javax.swing.tree.TreeModel;
   9 import javax.swing.tree.TreeNode;
  10 import javax.swing.tree.TreePath;
  11
  12 public class TreeSnapshot {
  13         private interface NodeAction {
  14                 public void run(TreeNode node);
  15         }
  16
  17         private JTree tree;
  18         private TreePath[] selectionPaths;
  19         private List<TreePath> expanded;
  20
  21         public TreeSnapshot(JTree tree) {
  22                 this.tree = tree;
  23
  24                 selectionPaths = tree.getSelectionPaths();
  25                 if (selectionPaths == null) {
  26                         selectionPaths = new TreePath[0];
  27                 }
  28
  29                 expanded = new ArrayList<TreePath>();
  30                 forEach(tree, new NodeAction() {
  31                         @Override
  32                         public void run(TreeNode node) {
  33                                 TreePath path = nodeToPath(node);
  34                                 if (path != null) {
  35                                         if (TreeSnapshot.this.tree.isExpanded(path)) {
  36                                                 expanded.add(path);
  37                                         }
  38                                 }
  39                         }
  40                 });
  41         }
  42
  43         public void apply() {
  44                 applyTo(tree);
  45         }
  46
  47         public void applyTo(JTree tree) {
  48                 final List<TreePath> newExpanded = new ArrayList<TreePath>();
  49                 final List<TreePath> newSlectionPaths = new ArrayList<TreePath>();
  50
  51                 forEach(tree, new NodeAction() {
  52                         @Override
  53                         public void run(TreeNode newNode) {
  54                                 TreePath newPath = nodeToPath(newNode);
  55                                 if (newPath != null) {
  56                                         for (TreePath path : selectionPaths) {
  57                                                 if (isSamePath(path, newPath)) {
  58                                                         newSlectionPaths.add(newPath);
  59                                                         if (expanded.contains(path)) {
  60                                                                 newExpanded.add(newPath);
  61                                                         }
  62                                                 }
  63                                         }
  64                                 }
  65                         }
  66                 });
  67
  68                 for (TreePath newPath : newExpanded) {
  69                         tree.expandPath(newPath);
  70                 }
  71
  72                 tree.setSelectionPaths(newSlectionPaths.toArray(new TreePath[0]));
  73         }
  74
  75         // You can override this
  76         protected boolean isSamePath(TreePath oldPath, TreePath newPath) {
  77                 return newPath.toString().equals(oldPath.toString());
  78         }
  79
  80         private void forEach(JTree tree, NodeAction action) {
  81                 forEach(tree.getModel(), tree.getModel().getRoot(), action);
  82         }
  83
  84         private void forEach(TreeModel model, Object parent, NodeAction action) {
  85                 if (!(parent instanceof TreeNode))
  86                         return;
  87
  88                 TreeNode node = (TreeNode) parent;
  89
  90                 action.run(node);
  91                 int count = model.getChildCount(node);
  92                 for (int i = 0; i < count; i++) {
  93                         Object child = model.getChild(node, i);
  94                         forEach(model, child, action);
  95                 }
  96         }
  97
  98         private static TreePath nodeToPath(TreeNode node) {
  99                 List<Object> nodes = new LinkedList<Object>();
 100                 if (node != null) {
 101                         nodes.add(node);
 102                         node = node.getParent();
 103                         while (node != null) {
 104                                 nodes.add(0, node);
 105                                 node = node.getParent();
 106                         }
 107                 }
 108
 109                 return nodes.isEmpty() ? null : new TreePath(nodes.toArray());
 110         }
 111
 112         @Override
 113         public String toString() {
 114                 StringBuilder builder = new StringBuilder();
 115                 builder.append("Tree Snapshot of: ").append(tree).append("\n");
 116                 builder.append("Selected paths:\n");
 117                 for (TreePath path : selectionPaths) {
 118                         builder.append("\t").append(path).append("\n");
 119                 }
 120                 builder.append("Expanded paths:\n");
 121                 for (TreePath epath : expanded) {
 122                         builder.append("\t").append(epath).append("\n");
 123                 }
 124
 125                 return builder.toString();
 126         }
 127 }