gridbagconstraints.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 318 行

/*
 * @(#)GridBagConstraints.java	1.19 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;

/**
 * The <code>GridBagConstraints</code> class specifies constraints 
 * for components that are laid out using the 
 * <code>GridBagLayout</code> class.
 *
 * @version 1.15, 08/19/02
 * @author Doug Stein
 * @see java.awt.GridBagLayout
 * @since JDK1.0
 */
public class GridBagConstraints implements Cloneable, java.io.Serializable {
    /**
     * Specify that this component is the next-to-last component in its 
     * column or row (<code>gridwidth</code>, <code>gridheight</code>), 
     * or that this component be placed next to the previously added 
     * component (<code>gridx</code>, <code>gridy</code>). 
     * @see      java.awt.GridBagConstraints#gridwidth
     * @see      java.awt.GridBagConstraints#gridheight
     * @see      java.awt.GridBagConstraints#gridx
     * @see      java.awt.GridBagConstraints#gridy
     * @since    JDK1.0
     */
    public static final int RELATIVE = -1;
    /**
     * Specify that this component is the 
     * last component in its column or row. 
     * @since   JDK1.0
     */
    public static final int REMAINDER = 0;
    /**
     * Do not resize the component. 
     * @since   JDK1.0
     */
    public static final int NONE = 0;
    /**
     * Resize the component both horizontally and vertically. 
     * @since   JDK1.0
     */
    public static final int BOTH = 1;
    /**
     * Resize the component horizontally but not vertically. 
     * @since   JDK1.0
     */
    public static final int HORIZONTAL = 2;
    /**
     * Resize the component vertically but not horizontally. 
     * @since   JDK1.0
     */
    public static final int VERTICAL = 3;
    /**
     * Put the component in the center of its display area.
     * @since    JDK1.0
     */
    public static final int CENTER = 10;
    /**
     * Put the component at the top of its display area,
     * centered horizontally. 
     * @since   JDK1.0
     */
    public static final int NORTH = 11;
    /**
     * Put the component at the top-right corner of its display area. 
     * @since   JDK1.0
     */
    public static final int NORTHEAST = 12;
    /**
     * Put the component on the right side of its display area, 
     * centered vertically.
     * @since    JDK1.0
     */
    public static final int EAST = 13;
    /**
     * Put the component at the bottom-right corner of its display area. 
     * @since   JDK1.0
     */
    public static final int SOUTHEAST = 14;
    /**
     * Put the component at the bottom of its display area, centered 
     * horizontally. 
     * @since   JDK1.0
     */
    public static final int SOUTH = 15;
    /**
     * Put the component at the bottom-left corner of its display area. 
     * @since   JDK1.0
     */
    public static final int SOUTHWEST = 16;
    /**
     * Put the component on the left side of its display area, 
     * centered vertically.
     * @since    JDK1.0
     */
    public static final int WEST = 17;
    /**
     * Put the component at the top-left corner of its display area. 
     * @since   JDK1.0
     */
    public static final int NORTHWEST = 18;
    /**
     * Specifies the cell at the left of the component's display area, 
     * where the leftmost cell has <code>gridx&nbsp;=&nbsp;0</code>. The value 
     * <code>RELATIVE</code> specifies that the component be placed just 
     * to the right of the component that was added to the container just 
     * before this component was added. 
     * <p>
     * The default value is <code>RELATIVE</code>. 
     * @see      java.awt.GridBagConstraints#gridy
     * @since    JDK1.0
     */
    public int gridx;
    /**
     * Specifies the cell at the top of the component's display area, 
     * where the topmost cell has <code>gridy&nbsp;=&nbsp;0</code>. The value 
     * <code>RELATIVE</code> specifies that the component be placed just 
     * below the component that was added to the container just before 
     * this component was added. 
     * <p>
     * The default value is <code>RELATIVE</code>. 
     * @see      java.awt.GridBagConstraints#gridx
     * @since    JDK1.0
     */
    public int gridy;
    /**
     * Specifies the number of cells in a row for the component's 
     * display area. 
     * <p>
     * Use <code>REMAINDER</code> to specify that the component be the 
     * last one in its row. Use <code>RELATIVE</code> to specify that the 
     * component be the next-to-last one in its row. 
     * <p>
     * The default value is 1. 
     * @see      java.awt.GridBagConstraints#gridheight
     * @since    JDK1.0
     */
    public int gridwidth;
    /**
     * Specifies the number of cells in a column for the component's 
     * display area. 
     * <p>
     * Use <code>REMAINDER</code> to specify that the component be the 
     * last one in its column. Use <code>RELATIVE</code> to specify that 
     * the component be the next-to-last one in its column. 
     * <p>
     * The default value is 1.
     * @see      java.awt.GridBagConstraints#gridwidth
     * @since    JDK1.0
     */
    public int gridheight;
    /**
     * Specifies how to distribute extra horizontal space. 
     * <p>
     * The grid bag layout manager calculates the weight of a column to 
     * be the maximum <code>weighty</code> of all the components in a 
     * row. If the resulting layout is smaller horizontally than the area 
     * it needs to fill, the extra space is distributed to each column in 
     * proportion to its weight. A column that has a weight zero receives no 
     * extra space. 
     * <p>
     * If all the weights are zero, all the extra space appears between 
     * the grids of the cell and the left and right edges. 
     * <p>
     * The default value of this field is <code>0</code>. 
     * @see      java.awt.GridBagConstraints#weighty
     * @since    JDK1.0
     */
    public double weightx;
    /**
     * Specifies how to distribute extra vertical space. 
     * <p>
     * The grid bag layout manager calculates the weight of a row to be 
     * the maximum <code>weightx</code> of all the components in a row. 
     * If the resulting layout is smaller vertically than the area it 
     * needs to fill, the extra space is distributed to each row in 
     * proportion to its weight. A row that has a weight of zero receives no 
     * extra space. 
     * <p>
     * If all the weights are zero, all the extra space appears between 
     * the grids of the cell and the top and bottom edges. 
     * <p>
     * The default value of this field is <code>0</code>. 
     * @see      java.awt.GridBagConstraints#weightx
     * @since    JDK1.0
     */
    public double weighty;
    /**
     * This field is used when the component is smaller than its display 
     * area. It determines where, within the display area, to place the 
     * component. Possible values are <code>CENTER<code>, 
     * <code>NORTH<code>, <code>NORTHEAST<code>, <code>EAST<code>, 
     * <code>SOUTHEAST<code>, <code>SOUTH<code>, <code>SOUTHWEST<code>, 
     * <code>WEST<code>, and <code>NORTHWEST<code>.
     * The default value is <code>CENTER</code>. 
     * @since    JDK1.0
     */
    public int anchor;
    /**
     * This field is used when the component's display area is larger 
     * than the component's requested size. It determines whether to 
     * resize the component, and if so, how. 
     * <p>
     * The following values are valid for <code>fill</code>: 
     * <p>
     * <ul>
     * <li>
     * <code>NONE</code>: Do not resize the component. 
     * <li>
     * <code>HORIZONTAL</code>: Make the component wide enough to fill 
     *         its display area horizontally, but do not change its height. 
     * <li>
     * <code>VERTICAL</code>: Make the component tall enough to fill its 
     *         display area vertically, but do not change its width. 
     * <li>
     * <code>BOTH</code>: Make the component fill its display area 
     *         entirely. 
     * </ul>
     * <p>
     * The default value is <code>NONE</code>. 
     * @since   JDK1.0
     */
    public int fill;
    /**
     * This field specifies the external padding of the component, the 
     * minimum amount of space between the component and the edges of its 
     * display area. 
     * <p>
     * The default value is <code>new Insets(0, 0, 0, 0)</code>. 
     * @since    JDK1.0
     */
    public Insets insets;
    /**
     * This field specifies the internal padding of the component, how much 
     * space to add to the minimum width of the component. The width of 
     * the component is at least its minimum width plus 
     * <code>(ipadx&nbsp;*&nbsp;2)</code> pixels. 
     * <p>
     * The default value is <code>0</code>. 
     * @see      java.awt.GridBagConstraints#ipady
     * @since    JDK1.0
     */
    public int ipadx;
    /**
     * This field specifies the internal padding, that is, how much 
     * space to add to the minimum height of the component. The height of 
     * the component is at least its minimum height plus 
     * <code>(ipady&nbsp;*&nbsp;2)</code> pixels. 
     * <p>
     * The default value is 0. 
     * @see      java.awt.GridBagConstraints#ipadx
     * @since    JDK1.0
     */
    public int ipady;
    int tempX, tempY;
    int tempWidth, tempHeight;
    int minWidth, minHeight;
    /**
     * Creates a <code>GridBagConstraint</code> object with 
     * all of its fields set to their default value. 
     * @since    JDK1.0
     */
    public GridBagConstraints () {
        gridx = RELATIVE;
        gridy = RELATIVE;
        gridwidth = 1;
        gridheight = 1;
        weightx = 0;
        weighty = 0;
        anchor = CENTER;
        fill = NONE;
        insets = new Insets(0, 0, 0, 0);
        ipadx = 0;
        ipady = 0;
    }

    /**
     * Creates a copy of this grid bag constraint.
     * @return     a copy of this grid bag constraint
     * @since      JDK1.0
     */
    public Object clone() {
        try { 
            GridBagConstraints c = (GridBagConstraints) super.clone();
            c.insets = (Insets) insets.clone();
            return c;
        } catch (CloneNotSupportedException e) { 
            // this shouldn't happen, since we are Cloneable
            throw new InternalError();
        }
    }
}