layoutmanager2.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 85 行

/*
 * @(#)LayoutManager2.java	1.14 06/10/10
 *
 * Copyright  1990-2008 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 only, as published by the Free Software Foundation. 
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt). 
 * 
 * You should have received a copy of the GNU General Public License
 * version 2 along with this work; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA 
 * 
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions. 
 *
 */
package java.awt;

/** 
 * Defines an interface for classes that know how to layout Containers
 * based on a layout constraints object.
 *
 * This interface extends the LayoutManager interface to deal with layouts
 * explicitly in terms of constraint objects that specify how and where
 * components should be added to the layout.
 * <p>
 * This minimal extension to LayoutManager is intended for tool
 * providers who wish to the creation of constraint-based layouts.
 * It does not yet provide full, general support for custom
 * constraint-based layout managers.
 *
 * @see LayoutManager
 * @see Container
 *
 * @version	1.10, 08/19/02
 * @author 	Jonni Kanerva
 */
public interface LayoutManager2 extends LayoutManager {
    /**
     * Adds the specified component to the layout, using the specified
     * constraint object.
     * @param comp the component to be added
     * @param constraints  where/how the component is added to the layout.
     */
    void addLayoutComponent(Component comp, Object constraints);
    /** 
     * Returns the maximum size of this component.
     * @see java.awt.Component#getMinimumSize()
     * @see java.awt.Component#getPreferredSize()
     * @see LayoutManager
     */
    public Dimension maximumLayoutSize(Container target);
    /**
     * Returns the alignment along the x axis.  This specifies how
     * the component would like to be aligned relative to other 
     * components.  The value should be a number between 0 and 1
     * where 0 represents alignment along the origin, 1 is aligned
     * the furthest away from the origin, 0.5 is centered, etc.
     */
    public float getLayoutAlignmentX(Container target);
    /**
     * Returns the alignment along the y axis.  This specifies how
     * the component would like to be aligned relative to other 
     * components.  The value should be a number between 0 and 1
     * where 0 represents alignment along the origin, 1 is aligned
     * the furthest away from the origin, 0.5 is centered, etc.
     */
    public float getLayoutAlignmentY(Container target);
    /**
     * Invalidates the layout, indicating that if the layout manager
     * has cached information it should be discarded.
     */
    public void invalidateLayout(Container target);
}