| /******************************************************************************* |
| * Copyright (c) 2000, 2016 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.snippets; |
| |
| /* |
| * Tree example snippet: create a tree (lazy) |
| * |
| * For a list of all SWT example snippets see |
| * http://www.eclipse.org/swt/snippets/ |
| */ |
| import java.io.*; |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.layout.*; |
| import org.eclipse.swt.widgets.*; |
| |
| public class Snippet8 { |
| |
| public static void main (String [] args) { |
| final Display display = new Display (); |
| final Shell shell = new Shell (display); |
| shell.setText ("Lazy Tree"); |
| shell.setLayout (new FillLayout ()); |
| final Tree tree = new Tree (shell, SWT.BORDER); |
| File [] roots = File.listRoots (); |
| for (int i=0; i<roots.length; i++) { |
| TreeItem root = new TreeItem (tree, 0); |
| root.setText (roots [i].toString ()); |
| root.setData (roots [i]); |
| new TreeItem (root, 0); |
| } |
| tree.addListener (SWT.Expand, event -> { |
| final TreeItem root = (TreeItem) event.item; |
| TreeItem [] items = root.getItems (); |
| for (int i1= 0; i1<items.length; i1++) { |
| if (items [i1].getData () != null) return; |
| items [i1].dispose (); |
| } |
| File file = (File) root.getData (); |
| File [] files = file.listFiles (); |
| if (files == null) return; |
| for (int i2= 0; i2<files.length; i2++) { |
| TreeItem item = new TreeItem (root, 0); |
| item.setText (files [i2].getName ()); |
| item.setData (files [i2]); |
| if (files [i2].isDirectory()) { |
| new TreeItem (item, 0); |
| } |
| } |
| }); |
| Point size = tree.computeSize (300, SWT.DEFAULT); |
| int width = Math.max (300, size.x); |
| int height = Math.max (300, size.y); |
| shell.setSize (shell.computeSize (width, height)); |
| shell.open (); |
| while (!shell.isDisposed ()) { |
| if (!display.readAndDispatch ()) display.sleep (); |
| } |
| display.dispose (); |
| } |
| } |