Changeset 6826

Timestamp:

2004-02-18T10:24:52+13:00 (20 years ago)

Author:

mdewsnip

Message:

Rewrote the refresh function, not necessarily because there was anything wrong with it, but just so I understand it now. It's a fair bit shorter and simpler (well to me, anyway!) now.

File:

• trunk/gli/src/org/greenstone/gatherer/file/FileSystemModel.java (modified) (2 diffs)

trunk/gli/src/org/greenstone/gatherer/file/FileSystemModel.java

@@ -18 +18 @@
     implements TreeExpansionListener, TreeWillExpandListener {
 
+    private int counter = 0;
     private DragTree tree;
     private FileFilter current_filter;
@@ -118 +119 @@
     }
 
+
+    public void refresh(TreePath path)
+    {
+    // If no path is set, take the path to the root node (ie. update the whole tree)
+    if (path == null) {
+        // System.err.println("\nFileSystemModel.refresh(entire tree).");
+        path = new TreePath(((FileNode) root).getPath());
+    }
+    // else {
+    //     System.err.println("\nFileSystemModel.refresh(" + path + ").");
+    // }
+
+    // Can only refresh if the model is currently being displayed in a tree
+    if (tree == null) {
+        return;
+    }
+
+    // Record all the expanded paths under this node
+    Enumeration old_expanded_paths_enumeration = tree.getExpandedDescendants(path);
+    if (old_expanded_paths_enumeration == null) {
+        return;
+    }
+
+    // Map and unmap the node to refresh its contents
+    FileNode node = (FileNode) path.getLastPathComponent();
+    node.unmap();
+    node.map();
+
+    // Sort the old expanded paths by length, smallest first
+    ArrayList old_expanded_paths_list = Collections.list(old_expanded_paths_enumeration);
+    Collections.sort(old_expanded_paths_list, new TreePathComparator());
+
+    // Restore each of the expanded paths
+    for (int i = 0; i < old_expanded_paths_list.size(); i++) {
+        TreePath old_expanded_path = (TreePath) old_expanded_paths_list.get(i);
+        // System.err.println("Expanded path: " + old_expanded_path);
+
+        // Build up the new path in the tree
+        TreePath current_path = new TreePath(path.getPath());
+        FileNode current_node = node;
+
+        // Traverse the tree to find the node to expand (or find it no longer exists)
+        while (!current_path.toString().equals(old_expanded_path.toString())) {
+        // System.err.println("Current path: " + current_path);
+
+        FileNode old_expanded_node =
+            (FileNode) old_expanded_path.getPathComponent(current_path.getPathCount());
+        // System.err.println("Looking for: " + old_expanded_node);
+
+        // Find the child node that matches the next element in the path
+        boolean found = false;
+        for (int j = 0; j < current_node.getChildCount(); j++) {
+            FileNode child_node = (FileNode) current_node.getChildAt(j);
+            // System.err.println("Child node: " + child_node);
+            if (child_node.equals(old_expanded_node)) {
+            // System.err.println("Found!");
+            current_path = current_path.pathByAddingChild(child_node);
+            current_node = child_node;
+            found = true;
+            break;
+            }
+        }
+
+        // The node was not found, so we cannot expand this path
+        if (!found) {
+            // System.err.println("Not found...");
+            break;
+        }
+        }
+
+        // If we have built up the correct path, expand it
+        if (current_path.toString().equals(old_expanded_path.toString())) {
+        tree.expandPath(current_path);
+        }
+    }
+    }
+
+
+    private class TreePathComparator
+    implements Comparator {
+
+    public int compare(Object o1, Object o2)
+    {
+        return (((TreePath) o1).getPathCount() - ((TreePath) o2).getPathCount());
+    }
+    }
+
+
     /** Used to refresh the contents of the FileNode indicated by the tree path. While the refresh itself is a piece of the proverbial, the restoring of expanded folders afterwards is a nightmare, mainly because all of the tree paths are no longer valid (remember that refresh involves throwing away the node currents children and remapping them).
      * @param path The TreePath to the node to be refreshed.
      */
-    public void refresh(TreePath path) {
-    // If no path is set, take the path to the root node (ie update the whole tree)
-    if(path == null) {
-        ///ystem.err.println("Refresh entire tree.");
-        path = new TreePath(((FileNode)root).getPath());
-    }
-    //else {
-    //    ///ystem.err.println("Refresh: " + path.getLastPathComponent());
-    //}
-    // Only a valid action if this model is currently being displayed in a tree.
-    if(tree != null) {
-        // Retrieve the error node.
-        FileNode node = (FileNode) path.getLastPathComponent();
-        // If this error node is a dummy node (ie has no associated file) we can't unmap it, so we iterate through its children refreshing each in turn. The exception being Greenstone Collections, as it is a dummy node but we can map/unmap it
-        if(node.getFile() == null && !node.toString().equals(Dictionary.get("Tree.World"))) {
-        for(int i = 0; i < node.getChildCount(); i++) {
-            FileNode child = (FileNode) node.getChildAt(i);
-            refresh(new TreePath(child.getPath()));
-            child = null;
-        }
-        }
-        // Otherwise we refresh this node.
-        else {
-        // Record all of the expanded paths under this node. How come getExpandedDescendants returns more results each time.
-        Enumeration old_tree_paths = tree.getExpandedDescendants(path);
-        // Refresh the tree structure.
-        node.unmap();
-        node.map();
-        // Fire the appropriate event.
-        nodeStructureChanged(node);
-        // Then (painfully) restore the expanded paths. Note that the paths stored in the enumeration no longer exist, so I have to restore by node matching.
-        //counter = 0;
-        ///ystem.err.println("After:");
-        while(old_tree_paths != null && old_tree_paths.hasMoreElements()) {
-            //counter++;
-            FileNode current_node = node;
-            TreePath old_tree_path = (TreePath) old_tree_paths.nextElement();
-            ///ystem.err.println(counter + ". " + old_tree_path);
-            TreePath new_tree_path = new TreePath(path.getPath()); // Why isn't there a treepath copy constructor!
-            boolean not_found = false;
-            while(!not_found && old_tree_path.getPathCount() > new_tree_path.getPathCount()) {
-            // Retrieve the new node in the old tree path
-            FileNode old_path_node = (FileNode) old_tree_path.getPathComponent(new_tree_path.getPathCount());
-            // Ensure the current node is mapped
-            current_node.map();
-            // Now attempt to match it to a child of the new paths last node.
-            boolean found = false;
-            for(int i = 0; !found && i < current_node.getChildCount(); i++) {
-                FileNode target = (FileNode) current_node.getChildAt(i);
-                ///ystem.err.println("Comparing " + old_path_node.toString() + " with " + target);
-                if(target.toString().equals(old_path_node.toString())) {
-                current_node = target;
-                found = true;
-                }
-                target = null;
-            }
-            old_path_node = null;
-            // If we found a match, we add that to the new Tree Path and continue.
-            if(found) {
-                ///ystem.err.println("Found a match!");
-                new_tree_path = new_tree_path.pathByAddingChild(current_node);
-            }
-            // We also have to record if we were unable to find a match in the current nodes children.
-            else {
-                ///ystem.err.println("Node not found.");
-                not_found = true;
-            }
-            }
-            old_tree_path = null;
-            // If we've got this far, and haven't hit a not found, then we can assume we have the appropriate path, and ask the program to expand the new tree path
-            if(!not_found) {
-            tree.expandPath(new_tree_path);
-            ///ystem.err.println(" -> Expanded " + new_tree_path);
-            }
-            else {
-            ///ystem.err.println(" -> Cannot Expand " + new_tree_path);
-            }
-            new_tree_path = null;
-            current_node = null;
-        }
-        node = null;
-        }
-    }
-    else {
-        ///ystem.err.println("No Tree!");
-    }
-    }
-
-    public void setFilter(String pattern) {
-    if(pattern != null) {
-        current_filter = new FileFilter(pattern, false);
-    }
-    else {
-        current_filter = null;
-    }
-    filters = null;
-    }
+//      public void oldRefresh(TreePath path) {
+//      // If no path is set, take the path to the root node (ie update the whole tree)
+//      if(path == null) {
+//          System.err.println("Refresh entire tree.");
+//          path = new TreePath(((FileNode)root).getPath());
+//      }
+//      else {
+//          System.err.println("FileSystemModel.refresh: " + path.getLastPathComponent());
+//      }
+//      // Only a valid action if this model is currently being displayed in a tree.
+//      if(tree != null) {
+//          System.err.println("Refreshing tree " + tree);
+//          // Retrieve the error node.
+//          FileNode node = (FileNode) path.getLastPathComponent();
+//          // If this error node is a dummy node (ie has no associated file) we can't unmap it, so we iterate through its children refreshing each in turn. The exception being Greenstone Collections, as it is a dummy node but we can map/unmap it
+//          if(node.getFile() == null && !node.toString().equals(Dictionary.get("Tree.World"))) {
+//          for(int i = 0; i < node.getChildCount(); i++) {
+//              FileNode child = (FileNode) node.getChildAt(i);
+//              refresh(new TreePath(child.getPath()));
+//              child = null;
+//          }
+//          }
+//          // Otherwise we refresh this node.
+//          else {
+//          // Record all of the expanded paths under this node. How come getExpandedDescendants returns more results each time.
+//          Enumeration old_tree_paths = tree.getExpandedDescendants(path);
+//          // Refresh the tree structure.
+//          node.unmap();
+//          node.map();
+//          // Fire the appropriate event.
+//          nodeStructureChanged(node);
+//          // Then (painfully) restore the expanded paths. Note that the paths stored in the enumeration no longer exist, so I have to restore by node matching.
+//          //counter = 0;
+//          ///ystem.err.println("After:");
+//          while(old_tree_paths != null && old_tree_paths.hasMoreElements()) {
+//              //counter++;
+//              FileNode current_node = node;
+//              TreePath old_tree_path = (TreePath) old_tree_paths.nextElement();
+//              ///ystem.err.println(counter + ". " + old_tree_path);
+//              TreePath new_tree_path = new TreePath(path.getPath()); // Why isn't there a treepath copy constructor!
+//              boolean not_found = false;
+//              while(!not_found && old_tree_path.getPathCount() > new_tree_path.getPathCount()) {
+//              // Retrieve the new node in the old tree path
+//              FileNode old_path_node = (FileNode) old_tree_path.getPathComponent(new_tree_path.getPathCount());
+//              // Ensure the current node is mapped
+//              current_node.map();
+//              // Now attempt to match it to a child of the new paths last node.
+//              boolean found = false;
+//              for(int i = 0; !found && i < current_node.getChildCount(); i++) {
+//                  FileNode target = (FileNode) current_node.getChildAt(i);
+//                  ///ystem.err.println("Comparing " + old_path_node.toString() + " with " + target);
+//                  if(target.toString().equals(old_path_node.toString())) {
+//                  current_node = target;
+//                  found = true;
+//                  }
+//                  target = null;
+//              }
+//              old_path_node = null;
+//              // If we found a match, we add that to the new Tree Path and continue.
+//              if(found) {
+//                  ///ystem.err.println("Found a match!");
+//                  new_tree_path = new_tree_path.pathByAddingChild(current_node);
+//              }
+//              // We also have to record if we were unable to find a match in the current nodes children.
+//              else {
+//                  ///ystem.err.println("Node not found.");
+//                  not_found = true;
+//              }
+//              }
+//              old_tree_path = null;
+//              // If we've got this far, and haven't hit a not found, then we can assume we have the appropriate path, and ask the program to expand the new tree path
+//              if(!not_found) {
+//              tree.expandPath(new_tree_path);
+//              ///ystem.err.println(" -> Expanded " + new_tree_path);
+//              }
+//              else {
+//              ///ystem.err.println(" -> Cannot Expand " + new_tree_path);
+//              }
+//              new_tree_path = null;
+//              current_node = null;
+//          }
+//          node = null;
+//          }
+//      }
+//      else {
+//          ///ystem.err.println("No Tree!");
+//      }
+//      }
+
+      public void setFilter(String pattern) {
+    if(pattern != null) {
+        current_filter = new FileFilter(pattern, false);
+    }
+    else {
+        current_filter = null;
+    }
+    filters = null;
+      }
 
     /* private void setPermanentFilter(String pattern) {