| /******************************************************************************* |
| * Copyright (c) 2000, 2004 IBM Corporation 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: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.snippets; |
| /* |
| * example snippet: Scroll table when mouse at top or bottom |
| * |
| * For a list of all SWT example snippets see |
| * http://www.eclipse.org/swt/snippets/ |
| */ |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.layout.*; |
| import org.eclipse.swt.widgets.*; |
| |
| public class Snippet221 { |
| static Runnable Heartbeat; |
| static boolean Tracking; |
| static int ScrollSpeed = 40; |
| |
| public static void main(String[] args) { |
| final Display display = new Display(); |
| Shell shell = new Shell(display); |
| shell.setLayout(new FillLayout()); |
| final Tree tree = new Tree(shell, SWT.FULL_SELECTION | SWT.BORDER); |
| tree.setHeaderVisible(true); |
| TreeColumn column0 = new TreeColumn(tree, SWT.LEFT); |
| column0.setText("Column 0"); |
| TreeColumn column1 = new TreeColumn(tree, SWT.LEFT); |
| column1.setText("Column 1"); |
| TreeColumn column2 = new TreeColumn(tree, SWT.LEFT); |
| column2.setText("Column 2"); |
| for (int i = 0; i < 9; i++) { |
| TreeItem item = new TreeItem(tree, SWT.NONE); |
| item.setText("item "+i); |
| item.setText(1, "column 1 - "+i); |
| item.setText(2, "column 2 - "+i); |
| for (int j = 0; j < 9; j++) { |
| TreeItem subItem = new TreeItem(item, SWT.NONE); |
| subItem.setText("item "+i+" "+j); |
| subItem.setText(1, "column 1 - "+i+" "+j); |
| subItem.setText(2, "column 2 - "+i+" "+j); |
| for (int k = 0; k < 9; k++) { |
| TreeItem subsubItem = new TreeItem(subItem, SWT.NONE); |
| subsubItem.setText("item "+i+" "+j+" "+k); |
| subsubItem.setText(1, "column 1 - "+i+" "+j+" "+k); |
| subsubItem.setText(2, "column 2 - "+i+" "+j+" "+k); |
| } |
| } |
| } |
| column0.pack(); |
| column1.pack(); |
| column2.pack(); |
| |
| Heartbeat = new Runnable() { |
| public void run() { |
| if (!Tracking || tree.isDisposed()) return; |
| Point cursor = display.getCursorLocation(); |
| cursor = display.map(null, tree, cursor); |
| Scroll(tree, cursor.x, cursor.y); |
| display.timerExec(ScrollSpeed, Heartbeat); |
| } |
| }; |
| Listener listener = new Listener() { |
| public void handleEvent(Event event) { |
| switch (event.type) { |
| case SWT.MouseEnter: |
| Tracking = true; |
| display.timerExec(0, Heartbeat); |
| break; |
| case SWT.MouseExit: |
| Tracking = false; |
| break; |
| } |
| } |
| }; |
| tree.addListener(SWT.MouseEnter, listener); |
| tree.addListener(SWT.MouseExit, listener); |
| shell.open(); |
| while (!shell.isDisposed()) { |
| if (!display.readAndDispatch()) |
| display.sleep(); |
| } |
| display.dispose(); |
| } |
| static void Scroll(Tree tree, int x, int y) { |
| TreeItem item = tree.getItem(new Point(x, y)); |
| if (item == null) return; |
| Rectangle area = tree.getClientArea(); |
| int headerHeight = tree.getHeaderHeight(); |
| int itemHeight= tree.getItemHeight(); |
| TreeItem nextItem = null; |
| if (y < area.y + headerHeight + 2 * itemHeight) { |
| nextItem = PreviousItem(tree, item); |
| } |
| if (y > area.y + area.height - 2 * itemHeight) { |
| nextItem = NextItem(tree, item); |
| } |
| if (nextItem != null) tree.showItem(nextItem); |
| } |
| |
| static TreeItem PreviousItem(Tree tree, TreeItem item) { |
| if (item == null) return null; |
| TreeItem childItem = item; |
| TreeItem parentItem = childItem.getParentItem(); |
| int index = parentItem == null ? tree.indexOf(childItem) : parentItem.indexOf(childItem); |
| if (index == 0) { |
| return parentItem; |
| } else { |
| TreeItem nextItem = parentItem == null ? tree.getItem(index-1) : parentItem.getItem(index-1); |
| int count = nextItem.getItemCount(); |
| while (count > 0 && nextItem.getExpanded()) { |
| nextItem = nextItem.getItem(count - 1); |
| count = nextItem.getItemCount(); |
| } |
| return nextItem; |
| } |
| } |
| static TreeItem NextItem(Tree tree, TreeItem item) { |
| if (item == null) return null; |
| if (item.getExpanded()) { |
| return item.getItem(0); |
| } else { |
| TreeItem childItem = item; |
| TreeItem parentItem = childItem.getParentItem(); |
| int index = parentItem == null ? tree.indexOf(childItem) : parentItem.indexOf(childItem); |
| int count = parentItem == null ? tree.getItemCount() : parentItem.getItemCount(); |
| while (true) { |
| if (index + 1 < count) { |
| return parentItem == null ? tree.getItem(index + 1) : parentItem.getItem(index + 1); |
| } else { |
| if (parentItem == null) { |
| return null; |
| } else { |
| childItem = parentItem; |
| parentItem = childItem.getParentItem(); |
| index = parentItem == null ? tree.indexOf(childItem) : parentItem.indexOf(childItem); |
| count = parentItem == null ? tree.getItemCount() : parentItem.getItemCount(); |
| } |
| } |
| } |
| } |
| } |
| } |