org.mihalis.opal/src/main/java/org/mihalis/opal/roundedToolbar/RoundedToolbar.java

/*******************************************************************************
 * Copyright (c) 2012 Laurent CARON. 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: Laurent CARON (laurent.caron at gmail dot com) - initial API and implementation
 *******************************************************************************/
package org.mihalis.opal.roundedToolbar;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Widget;
import org.mihalis.opal.utils.AdvancedPath;
import org.mihalis.opal.utils.SWTGraphicUtil;

/**
 * Instances of this class support the layout of selectable
 * rounded tool bar items.
 * <p>
 * The item children that may be added to instances of this class
 * must be of type <code>RoundedToolItem</code>.
 * </p>
 * <p>
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>NONE</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#toolbar">ToolBar, ToolItem snippets</a>
 */
public class RoundedToolbar extends Canvas {

	/** The items. */
	private final List<RoundedToolItem> items;
	
	/** The multi selection. */
	private boolean multiSelection;
	
	/** The corner radius. */
	private int cornerRadius;
	
	/** The start gradient color default. */
	private static Color START_GRADIENT_COLOR_DEFAULT = SWTGraphicUtil.getColorSafely(245, 245, 245);
	
	/** The end gradient color default. */
	private static Color END_GRADIENT_COLOR_DEFAULT = SWTGraphicUtil.getColorSafely(185, 185, 185);
	
	/** The border color. */
	static Color BORDER_COLOR = SWTGraphicUtil.getColorSafely(66, 66, 66);
	
	/** The start gradient color. */
	private Color START_GRADIENT_COLOR = START_GRADIENT_COLOR_DEFAULT;
	
	/** The end gradient color. */
	private Color END_GRADIENT_COLOR = END_GRADIENT_COLOR_DEFAULT;


	/**
	 * Constructs a new instance of this class given its parent and a style
	 * value describing its behavior and appearance.
	 * <p>
	 * The style value is either one of the style constants defined in class
	 * <code>SWT</code> which is applicable to instances of this class, or must
	 * be built by <em>bitwise OR</em>'ing together (that is, using the
	 * <code>int</code> "|" operator) two or more of those <code>SWT</code>
	 * style constants. The class description lists the style constants that are
	 * applicable to the class. Style bits are also inherited from superclasses.
	 * </p>
	 *
	 * @param parent a composite control which will be the parent of the new
	 *            instance (cannot be null)
	 * @param style the style of control to construct
	 * @see Widget#getStyle()
	 * @exception IllegalArgumentException <ul>
	 *                <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
	 *                </ul>
	 * @exception SWTException <ul>
	 *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
	 *                thread that created the parent</li>
	 *                <li>ERROR_INVALID_SUBCLASS - if this class is not an
	 *                allowed subclass</li>
	 *                </ul>
	 */
	public RoundedToolbar(final Composite parent, final int style) {
		super(parent, style | SWT.DOUBLE_BUFFERED);
		items = new ArrayList<RoundedToolItem>();
		cornerRadius = 2;
		addListeners();
	}

	/**
	 * Constructs a new instance of this class given its parent, a style value
	 * describing its behavior and appearance and colors to specify the start
	 * and end gradient of the rounded corner
	 * <p>
	 * The style value is either one of the style constants defined in class
	 * <code>SWT</code> which is applicable to instances of this class, or must
	 * be built by <em>bitwise OR</em>'ing together (that is, using the
	 * <code>int</code> "|" operator) two or more of those <code>SWT</code>
	 * style constants. The class description lists the style constants that are
	 * applicable to the class. Style bits are also inherited from superclasses.
	 * </p>
	 *
	 * @param parent a composite control which will be the parent of the new
	 *            instance (cannot be null)
	 * @param style the style of control to construct
	 * @param startGradientColor the start gradient color
	 * @param endGradientColor the end gradient color
	 * @see Widget#getStyle()
	 * @exception IllegalArgumentException <ul>
	 *                <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
	 *                </ul>
	 * @exception SWTException <ul>
	 *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
	 *                thread that created the parent</li>
	 *                <li>ERROR_INVALID_SUBCLASS - if this class is not an
	 *                allowed subclass</li>
	 *                </ul>
	 */
	public RoundedToolbar(final Composite parent, final int style,Color startGradientColor,Color endGradientColor) {
		super(parent, style | SWT.DOUBLE_BUFFERED);
		items = new ArrayList<RoundedToolItem>();
		cornerRadius = 2;
		addListeners();
		START_GRADIENT_COLOR=startGradientColor;
		END_GRADIENT_COLOR=endGradientColor;
	}

	/**
	 * Adds the listeners.
	 */
	private void addListeners() {
		addListener(SWT.MouseUp, new Listener() {
			@Override
			public void handleEvent(final Event event) {
				for (final RoundedToolItem item : items) {
					if (item.getBounds().contains(event.x, event.y)) {
						if (!multiSelection) {
							applyRadioBehaviour(item);
						}
						item.setSelection(!item.getSelection());
						item.fireSelectionEvent();
						redraw();
						update();
						return;
					}
				}
			}

			private void applyRadioBehaviour(final RoundedToolItem selectedItem) {
				for (final RoundedToolItem item : items) {
					if (!item.equals(selectedItem)) {
						item.setSelection(false);
						item.fireSelectionEvent();
					}
				}
			}
		});

		addListener(SWT.MouseHover, new Listener() {
			@Override
			public void handleEvent(final Event event) {
				for (final RoundedToolItem item : items) {
					if (item.getBounds().contains(event.x, event.y)) {
						setToolTipText(item.getTooltipText() == null ? "" : item.getTooltipText());
						return;
					}
				}
			}
		});

		addPaintListener(new PaintListener() {
			@Override
			public void paintControl(final PaintEvent e) {
				RoundedToolbar.this.paintControl(e);
			}
		});
	}

	/**
	 * Add an item to the toolbar.
	 *
	 * @param roundedToolItem roundedToolItem to add
	 */
	void addItem(final RoundedToolItem roundedToolItem) {
		items.add(roundedToolItem);
	}

	/**
	 * Compute size.
	 *
	 * @param wHint the w hint
	 * @param hHint the h hint
	 * @param changed the changed
	 * @return the point
	 * @see org.eclipse.swt.widgets.Composite#computeSize(int, int, boolean)
	 */
	@Override
	public Point computeSize(final int wHint, final int hHint, final boolean changed) {
		checkWidget();
		int width = 0, height = 0;
		for (final RoundedToolItem item : items) {
			width += item.getWidth();
			height = Math.max(height, item.getHeight());
		}
		return new Point(Math.max(width, wHint), Math.max(height, hHint));
	}

	/**
	 * Gets the corner radius.
	 *
	 * @return the corner radius
	 */
	public int getCornerRadius() {
		checkWidget();
		return this.cornerRadius;
	}

	/**
	 * Returns the item at the given, zero-relative index in the
	 * receiver. Throws an exception if the index is out of range.
	 *
	 * @param index the index of the item to return
	 * @return the item at the given index
	 *
	 * @exception IllegalArgumentException <ul>
	 *    <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)</li>
	 * </ul>
	 * @exception SWTException <ul>
	 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	 * </ul>
	 */
	public RoundedToolItem getItem(final int index) {
		checkWidget();
		if (index < 0 || index > items.size()) {
			SWT.error(SWT.ERROR_INVALID_ARGUMENT);
		}
		return items.get(index);
	}

	/**
	 * Returns the item at the given point in the receiver
	 * or null if no such item exists. The point is in the
	 * coordinate system of the receiver.
	 *
	 * @param point the point used to locate the item
	 * @return the item at the given point
	 *
	 * @exception IllegalArgumentException <ul>
	 *    <li>ERROR_NULL_ARGUMENT - if the point is null</li>
	 * </ul>
	 * @exception SWTException <ul>
	 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	 * </ul>
	 */
	public RoundedToolItem getItem(final Point point) {
		checkWidget();
		for (final RoundedToolItem item : items) {
			if (item.getBounds().contains(point)) {
				return item;
			}
		}
		return null;
	}

	/**
	 * Returns the number of items contained in the receiver.
	 *
	 * @return the number of items
	 *
	 * @exception SWTException <ul>
	 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	 * </ul>
	 */
	public int getItemCount() {
		checkWidget();
		return items.size();
	}

	/**
	 * Returns an array of <code>RoundedToolItem</code>s which are the items
	 * in the receiver. 
	 * <p>
	 * Note: This is not the actual structure used by the receiver
	 * to maintain its list of items, so modifying the array will
	 * not affect the receiver. 
	 * </p>
	 *
	 * @return the items in the receiver
	 *
	 * @exception SWTException <ul>
	 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	 * </ul>
	 */
	public RoundedToolItem[] getItems() {
		checkWidget();
		return items.toArray(new RoundedToolItem[items.size()]);
	}

	/**
	 * Searches the receiver's list starting at the first item
	 * (index 0) until an item is found that is equal to the 
	 * argument, and returns the index of that item. If no item
	 * is found, returns -1.
	 *
	 * @param item the search item
	 * @return the index of the item
	 *
	 * @exception IllegalArgumentException <ul>
	 *    <li>ERROR_NULL_ARGUMENT - if the tool item is null</li>
	 *    <li>ERROR_INVALID_ARGUMENT - if the tool item has been disposed</li>
	 * </ul>
	 * @exception SWTException <ul>
	 *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
	 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
	 * </ul>
	 */
	public int indexOf(final RoundedToolItem item) {
		checkWidget();
		return items.indexOf(item);
	}

	/**
	 * Checks if is multiselection.
	 *
	 * @return <code>true</code> if the toolbar is in multiselection mode,
	 *         <code>false</code> otherwise
	 */
	public boolean isMultiselection() {
		checkWidget();
		return this.multiSelection;
	}

	/**
	 * Paint the component.
	 *
	 * @param e event
	 */
	protected void paintControl(final PaintEvent e) {
		final GC gc = e.gc;
		gc.setAdvanced(true);
		gc.setAntialias(SWT.ON);

		final int width = getSize().x;
		final int height = getSize().y;

		drawBorders(gc, width, height);
		final Iterator<RoundedToolItem> it = items.iterator();
		int x = 0;
		while (it.hasNext()) {
			final RoundedToolItem item = it.next();
			item.drawButton(gc, x, height, !it.hasNext());
			x += item.getWidth();
		}
	}

	/**
	 * Draw borders.
	 *
	 * @param gc the gc
	 * @param width the width
	 * @param height the height
	 */
	private void drawBorders(final GC gc, final int width, final int height) {
		final AdvancedPath path = new AdvancedPath(getDisplay());
		path.addRoundRectangle(0, 0, width, height, cornerRadius, cornerRadius);
		gc.setClipping(path);

		gc.setForeground(START_GRADIENT_COLOR);
		gc.setBackground(END_GRADIENT_COLOR);
		gc.fillGradientRectangle(0, 0, width, height, true);

		gc.setForeground(BORDER_COLOR);
		gc.drawRoundRectangle(0, 0, width - 1, height - 1, cornerRadius, cornerRadius);

		gc.setClipping((Rectangle) null);
	}

	/**
	 * Add an item to the toolbar.
	 *
	 * @param roundedToolItem roundedToolItem to add
	 */
	void removeItem(final RoundedToolItem roundedToolItem) {
		checkWidget();
		items.remove(roundedToolItem);
	}

	/**
	 * Sets the corner radius.
	 *
	 * @param cornerRadius new corner radius
	 */
	public void setCornerRadius(final int cornerRadius) {
		checkWidget();
		this.cornerRadius = cornerRadius;
	}

	/**
	 * Sets the multiselection.
	 *
	 * @param multiSelection new value of the multi selection flag
	 */
	public void setMultiselection(final boolean multiSelection) {
		checkWidget();
		this.multiSelection = multiSelection;
	}

}