Create TreeView based on your own tree node structure : TreeViewer « SWT « Java Tutorial

1. Java Tutorial
2. SWT
3. TreeViewer

import java.util.Vector;

import org.eclipse.jface.viewers.ILabelProvider;
import org.eclipse.jface.viewers.ILabelProviderListener;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeItem;

public class TreeViewBasedOnNode {
  static Display display = new Display();

  static Shell shell = new Shell(display);

  static final Tree tree = new Tree(shell, SWT.BORDER);

  static Vector nodes = new Vector();

  public static void traditional() {
    for (int i = 0; nodes != null && i < nodes.size(); i++) {
      Node node = (Node) nodes.elementAt(i);
      addNode(null, node);
    }
  }

  private static void addNode(TreeItem parentItem, Node node) {
    TreeItem item = null;
    if (parentItem == null)
      item = new TreeItem(tree, SWT.NONE);
    else
      item = new TreeItem(parentItem, SWT.NONE);

    item.setText(node.getName());

    Vector subs = node.getSubCategories();
    for (int i = 0; subs != null && i < subs.size(); i++)
      addNode(item, (Node) subs.elementAt(i));
  }

  public static void main(String[] args) {
    Node category = new Node("A", null);
    nodes.add(category);

    category = new Node("a1", category);
    new Node("a11", category);
    new Node("a12", category);

    category = new Node("B", null);
    nodes.add(category);

    new Node("b1", category);
    new Node("b2", category);

    TreeViewer treeViewer = new TreeViewer(tree);

    treeViewer.setContentProvider(new MyTreeContentProvider());

    treeViewer.setLabelProvider(new MyLabelProvider());
    treeViewer.setInput(nodes);
    tree.setSize(300, 200);
    shell.setSize(300, 200);

    shell.open();

    while (!shell.isDisposed()) {
      if (!display.readAndDispatch()) {
        display.sleep();
      }
    }
    display.dispose();
  }

}
class MyLabelProvider implements ILabelProvider {
  public String getText(Object element) {
    return ((Node) element).getName();
  }

  public Image getImage(Object arg0) {
    return null;
  }

  public void addListener(ILabelProviderListener arg0) {
  }

  public void dispose() {
  }

  public boolean isLabelProperty(Object arg0, String arg1) {
    return false;
  }

  public void removeListener(ILabelProviderListener arg0) {
  }
}


class MyTreeContentProvider implements ITreeContentProvider{
  public Object[] getChildren(Object parentElement) {
    Vector subcats = ((Node) parentElement).getSubCategories();
    return subcats == null ? new Object[0] : subcats.toArray();
  }

  public Object getParent(Object element) {
    return ((Node) element).getParent();
  }

  public boolean hasChildren(Object element) {
    return ((Node) element).getSubCategories() != null;
  }

  public Object[] getElements(Object inputElement) {
    if (inputElement != null && inputElement instanceof Vector) {
      return ((Vector) inputElement).toArray();
    }
    return new Object[0];
  }

  public void dispose() {
  }

  public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
  }
}


class Node {
  private String name;

  private Vector subCategories;

  private Node parent;

  public Node(String name, Node parent) {
    this.name = name;
    this.parent = parent;
    if (parent != null)
      parent.addSubCategory(this);
  }

  public Vector getSubCategories() {
    return subCategories;
  }

  private void addSubCategory(Node subcategory) {
    if (subCategories == null)
      subCategories = new Vector();
    if (!subCategories.contains(subcategory))
      subCategories.add(subcategory);
  }

  public String getName() {
    return name;
  }

  public Node getParent() {
    return parent;
  }
}