/*******************************************************************************
* Copyright (c) 2000, 2008 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.wst.jsdt.internal.ui.actions;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.jface.action.Action;
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;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.keys.IBindingService;
/**
* A quick menu actions provides support to assign short cuts
* to sub menus.
*
*
*/
public abstract class QuickMenuAction extends Action {
private static final int CHAR_INDENT= 3;
/**
* Creates a new quick menu action with the given command id.
*
* @param commandId the command id of the short cut used to open
* the sub menu
*/
public QuickMenuAction(String commandId) {
setActionDefinitionId(commandId);
}
/**
* {@inheritDoc}
*/
public void run() {
Display display= Display.getCurrent();
if (display == null)
return;
Control focus= display.getFocusControl();
if (focus == null || focus.isDisposed())
return;
MenuManager menu= new MenuManager();
fillMenu(menu);
final Menu widget= menu.createContextMenu(focus.getShell());
Point location= computeMenuLocation(focus, widget);
if (location == null)
return;
widget.setLocation(location);
widget.setVisible(true);
while (!widget.isDisposed() && widget.isVisible()) {
if (!display.readAndDispatch())
display.sleep();
}
if (!widget.isDisposed()) {
widget.dispose();
}
}
/**
* Hook to fill a menu manager with the items of the sub menu.
*
* @param menu the sub menu to fill
*/
protected abstract void fillMenu(IMenuManager menu);
/**
* Adds the shortcut to the given menu text and returns it.
*
* @param menuText the menu text
* @return the menu text with the shortcut
*
*/
public String addShortcut(String menuText) {
String shortcut= getShortcutString();
if (menuText == null || shortcut == null)
return menuText;
return menuText + '\t' + shortcut;
}
/**
* Returns the shortcut assigned to the sub menu or <code>null</code> if
* no short cut is assigned.
*
* @return the shortcut as a human readable string or <code>null</code>
*/
private String getShortcutString() {
IBindingService bindingService= (IBindingService)PlatformUI.getWorkbench().getAdapter(IBindingService.class);
if (bindingService == null)
return null;
return bindingService.getBestActiveBindingFormattedFor(getActionDefinitionId());
}
private Point computeMenuLocation(Control focus, Menu menu) {
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
*/
protected Point computeMenuLocation(StyledText text) {
int offset= text.getCaretOffset();
Point result= text.getLocationAtOffset(offset);
result.y+= text.getLineHeight(offset);
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
*/
protected 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);
} else {
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
*/
protected 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);
} else {
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();
}
}
}