| /******************************************************************************* |
| * Copyright (c) 2006, 2007 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.ui.actions; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.eclipse.jface.action.IMenuManager; |
| import org.eclipse.jface.action.MenuManager; |
| import org.eclipse.swt.custom.StyledText; |
| import org.eclipse.swt.graphics.GC; |
| import org.eclipse.swt.graphics.Point; |
| import org.eclipse.swt.graphics.Rectangle; |
| import org.eclipse.swt.widgets.Control; |
| import org.eclipse.swt.widgets.Display; |
| import org.eclipse.swt.widgets.Menu; |
| import org.eclipse.swt.widgets.Table; |
| import org.eclipse.swt.widgets.TableItem; |
| import org.eclipse.swt.widgets.Tree; |
| import org.eclipse.swt.widgets.TreeItem; |
| |
| /** |
| * Abstract class that is capable of creating a context menu under the mouse |
| * pointer. |
| * |
| * @since 3.3 |
| */ |
| public abstract class QuickMenuCreator { |
| |
| private static final int CHAR_INDENT = 3; |
| |
| private Menu quickMenu; |
| |
| /** |
| * Create the context menu. |
| */ |
| public void createMenu() { |
| Display display = Display.getCurrent(); |
| if (display == null) { |
| return; |
| } |
| Control focus = display.getFocusControl(); |
| if (focus == null || focus.isDisposed()) { |
| return; |
| } |
| |
| MenuManager menu = new MenuManager(); |
| fillMenu(menu); |
| if (quickMenu != null) { |
| quickMenu.dispose(); |
| quickMenu = null; |
| } |
| quickMenu = menu.createContextMenu(focus.getShell()); |
| Point location = computeMenuLocation(focus); |
| if (location == null) { |
| return; |
| } |
| quickMenu.setLocation(location); |
| quickMenu.setVisible(true); |
| } |
| |
| /** |
| * Create the contents of the context menu. |
| * |
| * @param menu |
| * the menu to fill |
| */ |
| protected abstract void fillMenu(IMenuManager menu); |
| |
| /** |
| * Determine the optimal point for this menu to appear. |
| * |
| * @param focus |
| * the focus control |
| * @return the optimal placement |
| */ |
| private Point computeMenuLocation(Control focus) { |
| Point cursorLocation = focus.getDisplay().getCursorLocation(); |
| Rectangle clientArea = null; |
| Point result = null; |
| if (focus instanceof StyledText) { |
| StyledText styledText = (StyledText) focus; |
| clientArea = styledText.getClientArea(); |
| result = computeMenuLocation(styledText); |
| } else if (focus instanceof Tree) { |
| Tree tree = (Tree) focus; |
| clientArea = tree.getClientArea(); |
| result = computeMenuLocation(tree); |
| } else if (focus instanceof Table) { |
| Table table = (Table) focus; |
| clientArea = table.getClientArea(); |
| result = computeMenuLocation(table); |
| } |
| if (result == null) { |
| result = focus.toControl(cursorLocation); |
| } |
| if (clientArea != null && !clientArea.contains(result)) { |
| result = new Point(clientArea.x + clientArea.width / 2, |
| clientArea.y + clientArea.height / 2); |
| } |
| Rectangle shellArea = focus.getShell().getClientArea(); |
| if (!shellArea.contains(focus.getShell().toControl( |
| focus.toDisplay(result)))) { |
| result = new Point(shellArea.x + shellArea.width / 2, shellArea.y |
| + shellArea.height / 2); |
| } |
| return focus.toDisplay(result); |
| } |
| |
| /** |
| * Hook to compute the menu location if the focus widget is a styled text |
| * widget. |
| * |
| * @param text |
| * the styled text widget that has the focus |
| * |
| * @return a widget relative position of the menu to pop up or |
| * <code>null</code> if now position inside the widget can be |
| * computed |
| */ |
| private Point computeMenuLocation(StyledText text) { |
| Point result = text.getLocationAtOffset(text.getCaretOffset()); |
| result.y += text.getLineHeight(); |
| if (!text.getClientArea().contains(result)) { |
| return null; |
| } |
| return result; |
| } |
| |
| /** |
| * Hook to compute the menu location if the focus widget is a tree widget. |
| * |
| * @param tree |
| * the tree widget that has the focus |
| * |
| * @return a widget relative position of the menu to pop up or |
| * <code>null</code> if now position inside the widget can be |
| * computed |
| */ |
| private Point computeMenuLocation(Tree tree) { |
| TreeItem[] items = tree.getSelection(); |
| Rectangle clientArea = tree.getClientArea(); |
| switch (items.length) { |
| case 0: |
| return null; |
| case 1: |
| Rectangle bounds = items[0].getBounds(); |
| Rectangle intersect = clientArea.intersection(bounds); |
| if (intersect != null && intersect.height == bounds.height) { |
| return new Point(Math.max(0, bounds.x |
| + getAvarageCharWith(tree) * CHAR_INDENT), bounds.y |
| + bounds.height); |
| } |
| return null; |
| |
| default: |
| Rectangle[] rectangles = new Rectangle[items.length]; |
| for (int i = 0; i < rectangles.length; i++) { |
| rectangles[i] = items[i].getBounds(); |
| } |
| Point cursorLocation = tree.getDisplay().getCursorLocation(); |
| Point result = findBestLocation(getIncludedPositions(rectangles, |
| clientArea), tree.toControl(cursorLocation)); |
| if (result != null) { |
| result.x = result.x + getAvarageCharWith(tree) * CHAR_INDENT; |
| } |
| return result; |
| } |
| } |
| |
| /** |
| * Hook to compute the menu location if the focus widget is a table widget. |
| * |
| * @param table |
| * the table widget that has the focus |
| * |
| * @return a widget relative position of the menu to pop up or |
| * <code>null</code> if now position inside the widget can be |
| * computed |
| */ |
| private Point computeMenuLocation(Table table) { |
| TableItem[] items = table.getSelection(); |
| Rectangle clientArea = table.getClientArea(); |
| switch (items.length) { |
| case 0: { |
| return null; |
| } |
| case 1: { |
| Rectangle bounds = items[0].getBounds(0); |
| Rectangle iBounds = items[0].getImageBounds(0); |
| Rectangle intersect = clientArea.intersection(bounds); |
| if (intersect != null && intersect.height == bounds.height) { |
| return new Point(Math.max(0, bounds.x + iBounds.width |
| + getAvarageCharWith(table) * CHAR_INDENT), bounds.y |
| + bounds.height); |
| } |
| return null; |
| |
| } |
| default: { |
| Rectangle[] rectangles = new Rectangle[items.length]; |
| for (int i = 0; i < rectangles.length; i++) { |
| rectangles[i] = items[i].getBounds(0); |
| } |
| Rectangle iBounds = items[0].getImageBounds(0); |
| Point cursorLocation = table.getDisplay().getCursorLocation(); |
| Point result = findBestLocation(getIncludedPositions(rectangles, |
| clientArea), table.toControl(cursorLocation)); |
| if (result != null) { |
| result.x = result.x + iBounds.width + getAvarageCharWith(table) |
| * CHAR_INDENT; |
| } |
| return result; |
| } |
| } |
| } |
| |
| private Point[] getIncludedPositions(Rectangle[] rectangles, |
| Rectangle widgetBounds) { |
| List result = new ArrayList(); |
| for (int i = 0; i < rectangles.length; i++) { |
| Rectangle rectangle = rectangles[i]; |
| Rectangle intersect = widgetBounds.intersection(rectangle); |
| if (intersect != null && intersect.height == rectangle.height) { |
| result.add(new Point(intersect.x, intersect.y |
| + intersect.height)); |
| } |
| } |
| return (Point[]) result.toArray(new Point[result.size()]); |
| } |
| |
| private Point findBestLocation(Point[] points, Point relativeCursor) { |
| Point result = null; |
| double bestDist = Double.MAX_VALUE; |
| for (int i = 0; i < points.length; i++) { |
| Point point = points[i]; |
| int a = 0; |
| int b = 0; |
| if (point.x > relativeCursor.x) { |
| a = point.x - relativeCursor.x; |
| } else { |
| a = relativeCursor.x - point.x; |
| } |
| if (point.y > relativeCursor.y) { |
| b = point.y - relativeCursor.y; |
| } else { |
| b = relativeCursor.y - point.y; |
| } |
| double dist = Math.sqrt(a * a + b * b); |
| if (dist < bestDist) { |
| result = point; |
| bestDist = dist; |
| } |
| } |
| return result; |
| } |
| |
| private int getAvarageCharWith(Control control) { |
| GC gc = null; |
| try { |
| gc = new GC(control); |
| return gc.getFontMetrics().getAverageCharWidth(); |
| } finally { |
| if (gc != null) { |
| gc.dispose(); |
| } |
| } |
| } |
| |
| /** |
| * Dispose of this quick menu creator. Subclasses should ensure that they |
| * call this method. |
| */ |
| public void dispose() { |
| if (quickMenu != null) { |
| quickMenu.dispose(); |
| quickMenu = null; |
| } |
| } |
| } |