| /******************************************************************************* |
| * Copyright (c) 2006 Tom Schindl and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Tom Schindl - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.jface.snippets.viewers; |
| |
| import org.eclipse.jface.viewers.ILazyTreeContentProvider; |
| import org.eclipse.jface.viewers.LabelProvider; |
| import org.eclipse.jface.viewers.TreeViewer; |
| import org.eclipse.jface.viewers.Viewer; |
| import org.eclipse.swt.SWT; |
| import org.eclipse.swt.layout.FillLayout; |
| import org.eclipse.swt.widgets.Display; |
| import org.eclipse.swt.widgets.Shell; |
| |
| /** |
| * A simple TreeViewer to demonstrate usage of an ILazyContentProvider. |
| * |
| */ |
| public class Snippet047VirtualLazyTreeViewer { |
| private class MyContentProvider implements ILazyTreeContentProvider { |
| private TreeViewer viewer; |
| private IntermediateNode[] elements; |
| |
| public MyContentProvider(TreeViewer viewer) { |
| this.viewer = viewer; |
| } |
| |
| public void dispose() { |
| |
| } |
| |
| public void inputChanged(Viewer viewer, Object oldInput, Object newInput) { |
| this.elements = (IntermediateNode[]) newInput; |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see org.eclipse.jface.viewers.ILazyTreeContentProvider#getParent(java.lang.Object) |
| */ |
| public Object getParent(Object element) { |
| if (element instanceof LeafNode) |
| return ((LeafNode) element).parent; |
| return elements; |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see org.eclipse.jface.viewers.ILazyTreeContentProvider#updateChildCount(java.lang.Object, |
| * int) |
| */ |
| public void updateChildCount(Object element, int currentChildCount) { |
| |
| int length = 0; |
| if (element instanceof IntermediateNode) { |
| IntermediateNode node = (IntermediateNode) element; |
| length = node.children.length; |
| } |
| if(element == elements) |
| length = elements.length; |
| viewer.setChildCount(element, length); |
| |
| |
| } |
| |
| /* |
| * (non-Javadoc) |
| * |
| * @see org.eclipse.jface.viewers.ILazyTreeContentProvider#updateElement(java.lang.Object, |
| * int) |
| */ |
| public void updateElement(Object parent, int index) { |
| |
| Object element; |
| if (parent instanceof IntermediateNode) |
| element = ((IntermediateNode) parent).children[index]; |
| |
| else |
| element = elements[index]; |
| viewer.replace(parent, index, element); |
| updateChildCount(element, -1); |
| |
| } |
| |
| } |
| |
| public class LeafNode { |
| public int counter; |
| public IntermediateNode parent; |
| |
| public LeafNode(int counter, IntermediateNode parent) { |
| this.counter = counter; |
| this.parent = parent; |
| } |
| |
| public String toString() { |
| return "Leaf " + this.counter; |
| } |
| } |
| |
| public class IntermediateNode { |
| public int counter; |
| public LeafNode[] children = new LeafNode[0]; |
| |
| public IntermediateNode(int counter) { |
| this.counter = counter; |
| } |
| |
| public String toString() { |
| return "Node " + this.counter; |
| } |
| |
| public void generateChildren(int i) { |
| children = new LeafNode[i]; |
| for (int j = 0; j < i; j++) { |
| children[j] = new LeafNode(j, this); |
| } |
| |
| } |
| } |
| |
| public Snippet047VirtualLazyTreeViewer(Shell shell) { |
| final TreeViewer v = new TreeViewer(shell, SWT.VIRTUAL | SWT.BORDER); |
| v.setLabelProvider(new LabelProvider()); |
| v.setContentProvider(new MyContentProvider(v)); |
| v.setUseHashlookup(true); |
| IntermediateNode[] model = createModel(); |
| v.setInput(model); |
| v.getTree().setItemCount(model.length); |
| |
| } |
| |
| private IntermediateNode[] createModel() { |
| IntermediateNode[] elements = new IntermediateNode[10]; |
| |
| for (int i = 0; i < 10; i++) { |
| elements[i] = new IntermediateNode(i); |
| elements[i].generateChildren(1000); |
| } |
| |
| return elements; |
| } |
| |
| /** |
| * @param args |
| */ |
| public static void main(String[] args) { |
| Display display = new Display(); |
| Shell shell = new Shell(display); |
| shell.setLayout(new FillLayout()); |
| new Snippet047VirtualLazyTreeViewer(shell); |
| shell.open(); |
| |
| while (!shell.isDisposed()) { |
| if (!display.readAndDispatch()) |
| display.sleep(); |
| } |
| |
| display.dispose(); |
| |
| } |
| |
| } |