afocustraversalpolicy.java

Java写的ERP系统

/******************************************************************************
 * The contents of this file are subject to the   Compiere License  Version 1.1
 * ("License"); You may not use this file except in compliance with the License
 * You may obtain a copy of the License at http://www.compiere.org/license.html
 * Software distributed under the License is distributed on an  "AS IS"  basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
 * the specific language governing rights and limitations under the License.
 * The Original Code is                  Compiere  ERP & CRM  Business Solution
 * The Initial Developer of the Original Code is Jorg Janke  and ComPiere, Inc.
 * Portions created by Jorg Janke are Copyright (C) 1999-2001 Jorg Janke, parts
 * created by ComPiere are Copyright (C) ComPiere, Inc.;   All Rights Reserved.
 * Contributor(s): ______________________________________.
 *****************************************************************************/
package org.compiere.apps;

import java.awt.*;
import javax.swing.*;
import org.compiere.swing.*;

/**
 *  Compiere Application Focus Traversal Policy
 *
 *  @author     Jorg Janke
 *  @version    $Id: AFocusTraversalPolicy.java,v 1.3 2002/08/12 01:55:13 danb Exp $
 */
public class AFocusTraversalPolicy extends LayoutFocusTraversalPolicy
{
	/**
	 *  Get singleton
	 *  @return AFocusTraversalPolicy
	 */
	public static AFocusTraversalPolicy get()
	{
		if (s_policy == null)
			s_policy = new AFocusTraversalPolicy();
		return s_policy;
	}   //  get

	/** Default Policy          */
	private static AFocusTraversalPolicy s_policy = new AFocusTraversalPolicy();

	/*************************************************************************/

	/**
	 *  Constructor
	 */
	public AFocusTraversalPolicy ()
	{
		super();
	}   //  AFocusTraversalPolicy

	/**
	 * Returns the first Component in the traversal cycle. This method is used
	 * to determine the next Component to focus when traversal wraps in the
	 * forward direction.
	 *
	 * @param focusCycleRoot the focus cycle root whose first Component is to
	 *         be returned
	 * @return the first Component in the traversal cycle when focusCycleRoot
	 *         is the focus cycle root, or null if no suitable Component can be
	 *         found
	 * @throws IllegalArgumentException if focusCycleRoot is null
	 */
	public Component getFirstComponent(Container focusCycleRoot)
	{
		Component c = super.getFirstComponent(focusCycleRoot);
	//	info ("Root: ", focusCycleRoot);
	//	info ("  First: ", c);
		return c;
	}   //  getFirstComponent

	/**
	 * Returns the Component that should receive the focus after aComponent.
	 * focusCycleRoot must be a focus cycle root of aComponent.
	 * <p>
	 * By default, LayoutFocusTraversalPolicy implicitly transfers focus down-
	 * cycle. That is, during normal focus traversal, the Component
	 * traversed after a focus cycle root will be the focus-cycle-root's
	 * default Component to focus. This behavior can be disabled using the
	 * <code>setImplicitDownCycleTraversal</code> method.
	 *
	 * @param focusCycleRoot a focus cycle root of aComponent
	 * @param aComponent a (possibly indirect) child of focusCycleRoot, or
	 *        focusCycleRoot itself
	 * @return the Component that should receive the focus after aComponent, or
	 *         null if no suitable Component can be found
	 * @throws IllegalArgumentException if focusCycleRoot is not a focus cycle
	 *         root of aComponent, or if either focusCycleRoot or aComponent is
	 *         null
	 */
	public Component getComponentAfter(Container focusCycleRoot, Component aComponent)
	{
		Component c = super.getComponentAfter(focusCycleRoot, aComponent);
		return c;
	}

	/**
	 * Returns the Component that should receive the focus before aComponent.
	 * focusCycleRoot must be a focus cycle root of aComponent.
	 * <p>
	 * By default, LayoutFocusTraversalPolicy implicitly transfers focus down-
	 * cycle. That is, during normal focus traversal, the Component
	 * traversed after a focus cycle root will be the focus-cycle-root's
	 * default Component to focus. This behavior can be disabled using the
	 * <code>setImplicitDownCycleTraversal</code> method.
	 *
	 * @param focusCycleRoot a focus cycle root of aComponent
	 * @param aComponent a (possibly indirect) child of focusCycleRoot, or
	 *        focusCycleRoot itself
	 * @return the Component that should receive the focus before aComponent,
	 *         or null if no suitable Component can be found
	 * @throws IllegalArgumentException if focusCycleRoot is not a focus cycle
	 *         root of aComponent, or if either focusCycleRoot or aComponent is
	 *         null
	 */
	public Component getComponentBefore(Container focusCycleRoot, Component aComponent)
	{
		Component c = super.getComponentBefore(focusCycleRoot, aComponent);
		return c;
	}

	/**
	 * Returns the last Component in the traversal cycle. This method is used
	 * to determine the next Component to focus when traversal wraps in the
	 * reverse direction.
	 *
	 * @param focusCycleRoot the focus cycle root whose last Component is to be
	 *        returned
	 * @return the last Component in the traversal cycle when focusCycleRoot is
	 *         the focus cycle root, or null if no suitable Component can be
	 *         found
	 * @throws IllegalArgumentException if focusCycleRoot is null
	 */
	public Component getLastComponent(Container focusCycleRoot)
	{
		Component c = super.getLastComponent(focusCycleRoot);
		return c;
	}

	/**
	 * Determines whether the specified <code>Component</code>
	 * is an acceptable choice as the new focus owner.
	 * This method performs the following sequence of operations:
	 * <ol>
	 * <li>Checks whether <code>aComponent</code> is visible, displayable,
	 *     enabled, and focusable.  If any of these properties is
	 *     <code>false</code>, this method returns <code>false</code>.
	 * <li>If <code>aComponent</code> is an instance of <code>JTable</code>,
	 *     returns <code>true</code>.
	 * <li>If <code>aComponent</code> is an instance of <code>JComboBox</code>,
	 *     then returns the value of
	 *     <code>aComponent.getUI().isFocusTraversable(aComponent)</code>.
	 * <li>If <code>aComponent</code> is a <code>JComponent</code>
	 *     with a <code>JComponent.WHEN_FOCUSED</code>
	 *     <code>InputMap</code> that is neither <code>null</code>
	 *     nor empty, returns <code>true</code>.
	 * <li>Returns the value of
	 *     <code>DefaultFocusTraversalPolicy.accept(aComponent)</code>.
	 * </ol>
	 *
	 * @param aComponent the <code>Component</code> whose fitness
	 *                   as a focus owner is to be tested
	 * @see java.awt.Component#isVisible
	 * @see java.awt.Component#isDisplayable
	 * @see java.awt.Component#isEnabled
	 * @see java.awt.Component#isFocusable
	 * @see javax.swing.plaf.ComboBoxUI#isFocusTraversable
	 * @see javax.swing.JComponent#getInputMap
	 * @see java.awt.DefaultFocusTraversalPolicy#accept
	 * @return <code>true</code> if <code>aComponent</code> is a valid choice
	 *         for a focus owner;
	 *         otherwise <code>false</code>
	 */
	protected boolean accept(Component aComponent)
	{
		if (!super.accept(aComponent))
			return false;

		//  TabbedPane
		if (aComponent instanceof JTabbedPane)
			return false;
		//  R/O Editors
		if (aComponent instanceof CEditor)
		{
			CEditor ed = (CEditor)aComponent;
			if (!ed.isReadWrite())
				return false;
		}
		//  Toolbar Buttons
		if (aComponent.getParent() instanceof JToolBar)
			return false;
		//
		return true;
	}   //  accept

	/*************************************************************************/

	/**
	 *  Dump info
	 *  @param title
	 *  @param c
	 */
	private void info (String title, Component c)
	{
		System.out.print (title);
		System.out.print (c.getClass().getName());
		System.out.println (" - " + c.getName());
	}   //  info

}   //  AFocusTraversalPolicy