Java tutorial
/* * Copyright (c) 1995, 2018, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code 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. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 in the LICENSE file that * accompanied this code). * * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.awt; import java.util.Hashtable; import java.util.Arrays; /** * The {@code GridBagLayout} class is a flexible layout * manager that aligns components vertically, horizontally or along their * baseline without requiring that the components be of the same size. * Each {@code GridBagLayout} object maintains a dynamic, * rectangular grid of cells, with each component occupying * one or more cells, called its <em>display area</em>. * <p> * Each component managed by a {@code GridBagLayout} is associated with * an instance of {@link GridBagConstraints}. The constraints object * specifies where a component's display area should be located on the grid * and how the component should be positioned within its display area. In * addition to its constraints object, the {@code GridBagLayout} also * considers each component's minimum and preferred sizes in order to * determine a component's size. * <p> * The overall orientation of the grid depends on the container's * {@link ComponentOrientation} property. For horizontal left-to-right * orientations, grid coordinate (0,0) is in the upper left corner of the * container with x increasing to the right and y increasing downward. For * horizontal right-to-left orientations, grid coordinate (0,0) is in the upper * right corner of the container with x increasing to the left and y * increasing downward. * <p> * To use a grid bag layout effectively, you must customize one or more * of the {@code GridBagConstraints} objects that are associated * with its components. You customize a {@code GridBagConstraints} * object by setting one or more of its instance variables: * * <dl> * <dt>{@link GridBagConstraints#gridx}, * {@link GridBagConstraints#gridy} * <dd>Specifies the cell containing the leading corner of the component's * display area, where the cell at the origin of the grid has address * <code>gridx = 0</code>, * <code>gridy = 0</code>. For horizontal left-to-right layout, * a component's leading corner is its upper left. For horizontal * right-to-left layout, a component's leading corner is its upper right. * Use {@code GridBagConstraints.RELATIVE} (the default value) * to specify that the component be placed immediately following * (along the x axis for {@code gridx} or the y axis for * {@code gridy}) the component that was added to the container * just before this component was added. * <dt>{@link GridBagConstraints#gridwidth}, * {@link GridBagConstraints#gridheight} * <dd>Specifies the number of cells in a row (for {@code gridwidth}) * or column (for {@code gridheight}) * in the component's display area. * The default value is 1. * Use {@code GridBagConstraints.REMAINDER} to specify * that the component's display area will be from {@code gridx} * to the last cell in the row (for {@code gridwidth}) * or from {@code gridy} to the last cell in the column * (for {@code gridheight}). * * Use {@code GridBagConstraints.RELATIVE} to specify * that the component's display area will be from {@code gridx} * to the next to the last cell in its row (for {@code gridwidth}) * or from {@code gridy} to the next to the last cell in its * column (for {@code gridheight}). * * <dt>{@link GridBagConstraints#fill} * <dd>Used when the component's display area * is larger than the component's requested size * to determine whether (and how) to resize the component. * Possible values are * {@code GridBagConstraints.NONE} (the default), * {@code GridBagConstraints.HORIZONTAL} * (make the component wide enough to fill its display area * horizontally, but don't change its height), * {@code GridBagConstraints.VERTICAL} * (make the component tall enough to fill its display area * vertically, but don't change its width), and * {@code GridBagConstraints.BOTH} * (make the component fill its display area entirely). * <dt>{@link GridBagConstraints#ipadx}, * {@link GridBagConstraints#ipady} * <dd>Specifies the component's internal padding within the layout, * how much to add to the minimum size of the component. * The width of the component will be at least its minimum width * plus {@code ipadx} pixels. Similarly, the height of * the component will be at least the minimum height plus * {@code ipady} pixels. * <dt>{@link GridBagConstraints#insets} * <dd>Specifies the component's external padding, the minimum * amount of space between the component and the edges of its display area. * <dt>{@link GridBagConstraints#anchor} * <dd>Specifies where the component should be positioned in its display area. * There are three kinds of possible values: absolute, orientation-relative, * and baseline-relative * Orientation relative values are interpreted relative to the container's * {@code ComponentOrientation} property while absolute values * are not. Baseline relative values are calculated relative to the * baseline. Valid values are: * * <table class="striped" style="margin: 0px auto"> * <caption>Absolute, relative and baseline values as described above</caption> * <thead> * <tr> * <th><p style="text-align:center">Absolute Values</th> * <th><p style="text-align:center">Orientation Relative Values</th> * <th><p style="text-align:center">Baseline Relative Values</th> * </tr> * </thead> * <tbody> * <tr> * <td> * <ul style="list-style-type:none"> * <li>{@code GridBagConstraints.NORTH}</li> * <li>{@code GridBagConstraints.SOUTH}</li> * <li>{@code GridBagConstraints.WEST}</li> * <li>{@code GridBagConstraints.EAST}</li> * <li>{@code GridBagConstraints.NORTHWEST}</li> * <li>{@code GridBagConstraints.NORTHEAST}</li> * <li>{@code GridBagConstraints.SOUTHWEST}</li> * <li>{@code GridBagConstraints.SOUTHEAST}</li> * <li>{@code GridBagConstraints.CENTER} (the default)</li> * </ul> * </td> * <td> * <ul style="list-style-type:none"> * <li>{@code GridBagConstraints.PAGE_START}</li> * <li>{@code GridBagConstraints.PAGE_END}</li> * <li>{@code GridBagConstraints.LINE_START}</li> * <li>{@code GridBagConstraints.LINE_END}</li> * <li>{@code GridBagConstraints.FIRST_LINE_START}</li> * <li>{@code GridBagConstraints.FIRST_LINE_END}</li> * <li>{@code GridBagConstraints.LAST_LINE_START}</li> * <li>{@code GridBagConstraints.LAST_LINE_END}</li> * </ul> * </td> * <td> * <ul style="list-style-type:none"> * <li>{@code GridBagConstraints.BASELINE}</li> * <li>{@code GridBagConstraints.BASELINE_LEADING}</li> * <li>{@code GridBagConstraints.BASELINE_TRAILING}</li> * <li>{@code GridBagConstraints.ABOVE_BASELINE}</li> * <li>{@code GridBagConstraints.ABOVE_BASELINE_LEADING}</li> * <li>{@code GridBagConstraints.ABOVE_BASELINE_TRAILING}</li> * <li>{@code GridBagConstraints.BELOW_BASELINE}</li> * <li>{@code GridBagConstraints.BELOW_BASELINE_LEADING}</li> * <li>{@code GridBagConstraints.BELOW_BASELINE_TRAILING}</li> * </ul> * </td> * </tr> * </tbody> * </table> * <dt>{@link GridBagConstraints#weightx}, * {@link GridBagConstraints#weighty} * <dd>Used to determine how to distribute space, which is * important for specifying resizing behavior. * Unless you specify a weight for at least one component * in a row ({@code weightx}) and column ({@code weighty}), * all the components clump together in the center of their container. * This is because when the weight is zero (the default), * the {@code GridBagLayout} object puts any extra space * between its grid of cells and the edges of the container. * </dl> * <p> * Each row may have a baseline; the baseline is determined by the * components in that row that have a valid baseline and are aligned * along the baseline (the component's anchor value is one of {@code * BASELINE}, {@code BASELINE_LEADING} or {@code BASELINE_TRAILING}). * If none of the components in the row has a valid baseline, the row * does not have a baseline. * <p> * If a component spans rows it is aligned either to the baseline of * the start row (if the baseline-resize behavior is {@code * CONSTANT_ASCENT}) or the end row (if the baseline-resize behavior * is {@code CONSTANT_DESCENT}). The row that the component is * aligned to is called the <em>prevailing row</em>. * <p> * The following figure shows a baseline layout and includes a * component that spans rows: * <table class="borderless" style="margin: 0px auto"> * <caption>Baseline Layout</caption> * <tr style="text-align:center"> * <td> * <img src="doc-files/GridBagLayout-baseline.png" * alt="The following text describes this graphic (Figure 1)." style="float:center"> * </td> * </table> * This layout consists of three components: * <ul><li>A panel that starts in row 0 and ends in row 1. The panel * has a baseline-resize behavior of {@code CONSTANT_DESCENT} and has * an anchor of {@code BASELINE}. As the baseline-resize behavior * is {@code CONSTANT_DESCENT} the prevailing row for the panel is * row 1. * <li>Two buttons, each with a baseline-resize behavior of * {@code CENTER_OFFSET} and an anchor of {@code BASELINE}. * </ul> * Because the second button and the panel share the same prevailing row, * they are both aligned along their baseline. * <p> * Components positioned using one of the baseline-relative values resize * differently than when positioned using an absolute or orientation-relative * value. How components change is dictated by how the baseline of the * prevailing row changes. The baseline is anchored to the * bottom of the display area if any components with the same prevailing row * have a baseline-resize behavior of {@code CONSTANT_DESCENT}, * otherwise the baseline is anchored to the top of the display area. * The following rules dictate the resize behavior: * <ul> * <li>Resizable components positioned above the baseline can only * grow as tall as the baseline. For example, if the baseline is at 100 * and anchored at the top, a resizable component positioned above the * baseline can never grow more than 100 units. * <li>Similarly, resizable components positioned below the baseline can * only grow as high as the difference between the display height and the * baseline. * <li>Resizable components positioned on the baseline with a * baseline-resize behavior of {@code OTHER} are only resized if * the baseline at the resized size fits within the display area. If * the baseline is such that it does not fit within the display area * the component is not resized. * <li>Components positioned on the baseline that do not have a * baseline-resize behavior of {@code OTHER} * can only grow as tall as {@code display height - baseline + baseline of component}. * </ul> * If you position a component along the baseline, but the * component does not have a valid baseline, it will be vertically centered * in its space. Similarly if you have positioned a component relative * to the baseline and none of the components in the row have a valid * baseline the component is vertically centered. * <p> * The following figures show ten components (all buttons) * managed by a grid bag layout. Figure 2 shows the layout for a horizontal, * left-to-right container and Figure 3 shows the layout for a horizontal, * right-to-left container. * * <table class="borderless" style="margin: 0px auto"> * <caption style="width:600;display:none">Figures</caption> * <tr style="text-align:center"> * <td> * <img src="doc-files/GridBagLayout-1.gif" alt="The preceding text describes this graphic (Figure 1)." style="float:center; margin: 7px 10px;"> * </td> * <td> * <img src="doc-files/GridBagLayout-2.gif" alt="The preceding text describes this graphic (Figure 2)." style="float:center; margin: 7px 10px;"> * </td> * <tr style="text-align:center"> * <td>Figure 2: Horizontal, Left-to-Right</td> * <td>Figure 3: Horizontal, Right-to-Left</td> * </tr> * </table> * <p> * Each of the ten components has the {@code fill} field * of its associated {@code GridBagConstraints} object * set to {@code GridBagConstraints.BOTH}. * In addition, the components have the following non-default constraints: * * <ul> * <li>Button1, Button2, Button3: <code>weightx = 1.0</code> * <li>Button4: <code>weightx = 1.0</code>, * <code>gridwidth = GridBagConstraints.REMAINDER</code> * <li>Button5: <code>gridwidth = GridBagConstraints.REMAINDER</code> * <li>Button6: <code>gridwidth = GridBagConstraints.RELATIVE</code> * <li>Button7: <code>gridwidth = GridBagConstraints.REMAINDER</code> * <li>Button8: <code>gridheight = 2</code>, * <code>weighty = 1.0</code> * <li>Button9, Button 10: * <code>gridwidth = GridBagConstraints.REMAINDER</code> * </ul> * <p> * Here is the code that implements the example shown above: * * <hr><blockquote><pre> * import java.awt.*; * import java.util.*; * import java.applet.Applet; * * public class GridBagEx1 extends Applet { * * protected void makebutton(String name, * GridBagLayout gridbag, * GridBagConstraints c) { * Button button = new Button(name); * gridbag.setConstraints(button, c); * add(button); * } * * public void init() { * GridBagLayout gridbag = new GridBagLayout(); * GridBagConstraints c = new GridBagConstraints(); * * setFont(new Font("SansSerif", Font.PLAIN, 14)); * setLayout(gridbag); * * c.fill = GridBagConstraints.BOTH; * c.weightx = 1.0; * makebutton("Button1", gridbag, c); * makebutton("Button2", gridbag, c); * makebutton("Button3", gridbag, c); * * c.gridwidth = GridBagConstraints.REMAINDER; //end row * makebutton("Button4", gridbag, c); * * c.weightx = 0.0; //reset to the default * makebutton("Button5", gridbag, c); //another row * * c.gridwidth = GridBagConstraints.RELATIVE; //next-to-last in row * makebutton("Button6", gridbag, c); * * c.gridwidth = GridBagConstraints.REMAINDER; //end row * makebutton("Button7", gridbag, c); * * c.gridwidth = 1; //reset to the default * c.gridheight = 2; * c.weighty = 1.0; * makebutton("Button8", gridbag, c); * * c.weighty = 0.0; //reset to the default * c.gridwidth = GridBagConstraints.REMAINDER; //end row * c.gridheight = 1; //reset to the default * makebutton("Button9", gridbag, c); * makebutton("Button10", gridbag, c); * * setSize(300, 100); * } * * public static void main(String args[]) { * Frame f = new Frame("GridBag Layout Example"); * GridBagEx1 ex1 = new GridBagEx1(); * * ex1.init(); * * f.add("Center", ex1); * f.pack(); * f.setSize(f.getPreferredSize()); * f.show(); * } * } * </pre></blockquote><hr> * * @author Doug Stein * @author Bill Spitzak (orignial NeWS & OLIT implementation) * @see java.awt.GridBagConstraints * @see java.awt.GridBagLayoutInfo * @see java.awt.ComponentOrientation * @since 1.0 */ public class GridBagLayout implements LayoutManager2, java.io.Serializable { static final int EMPIRICMULTIPLIER = 2; /** * This field is no longer used to reserve arrays and kept for backward * compatibility. Previously, this was * the maximum number of grid positions (both horizontal and * vertical) that could be laid out by the grid bag layout. * Current implementation doesn't impose any limits * on the size of a grid. */ protected static final int MAXGRIDSIZE = 512; /** * The smallest grid that can be laid out by the grid bag layout. */ protected static final int MINSIZE = 1; /** * The preferred grid size that can be laid out by the grid bag layout. */ protected static final int PREFERREDSIZE = 2; /** * This hashtable maintains the association between * a component and its gridbag constraints. * The Keys in {@code comptable} are the components and the * values are the instances of {@code GridBagConstraints}. * * @serial * @see java.awt.GridBagConstraints */ protected Hashtable<Component, GridBagConstraints> comptable; /** * This field holds a gridbag constraints instance * containing the default values, so if a component * does not have gridbag constraints associated with * it, then the component will be assigned a * copy of the {@code defaultConstraints}. * * @serial * @see #getConstraints(Component) * @see #setConstraints(Component, GridBagConstraints) * @see #lookupConstraints(Component) */ protected GridBagConstraints defaultConstraints; /** * This field holds the layout information * for the gridbag. The information in this field * is based on the most recent validation of the * gridbag. * If {@code layoutInfo} is {@code null} * this indicates that there are no components in * the gridbag or if there are components, they have * not yet been validated. * * @serial * @see #getLayoutInfo(Container, int) */ protected GridBagLayoutInfo layoutInfo; /** * This field holds the overrides to the column minimum * width. If this field is non-{@code null} the values are * applied to the gridbag after all of the minimum columns * widths have been calculated. * If columnWidths has more elements than the number of * columns, columns are added to the gridbag to match * the number of elements in columnWidth. * * @serial * @see #getLayoutDimensions() */ public int[] columnWidths; /** * This field holds the overrides to the row minimum * heights. If this field is non-{@code null} the values are * applied to the gridbag after all of the minimum row * heights have been calculated. * If {@code rowHeights} has more elements than the number of * rows, rows are added to the gridbag to match * the number of elements in {@code rowHeights}. * * @serial * @see #getLayoutDimensions() */ public int[] rowHeights; /** * This field holds the overrides to the column weights. * If this field is non-{@code null} the values are * applied to the gridbag after all of the columns * weights have been calculated. * If {@code columnWeights[i] >} weight for column i, then * column i is assigned the weight in {@code columnWeights[i]}. * If {@code columnWeights} has more elements than the number * of columns, the excess elements are ignored - they do * not cause more columns to be created. * * @serial */ public double[] columnWeights; /** * This field holds the overrides to the row weights. * If this field is non-{@code null} the values are * applied to the gridbag after all of the rows * weights have been calculated. * If {@code rowWeights[i] > } weight for row i, then * row i is assigned the weight in {@code rowWeights[i]}. * If {@code rowWeights} has more elements than the number * of rows, the excess elements are ignored - they do * not cause more rows to be created. * * @serial */ public double[] rowWeights; /** * The component being positioned. This is set before calling into * {@code adjustForGravity}. */ private Component componentAdjusting; /** * Creates a grid bag layout manager. */ public GridBagLayout() { comptable = new Hashtable<Component, GridBagConstraints>(); defaultConstraints = new GridBagConstraints(); } /** * Sets the constraints for the specified component in this layout. * @param comp the component to be modified * @param constraints the constraints to be applied */ public void setConstraints(Component comp, GridBagConstraints constraints) { comptable.put(comp, (GridBagConstraints) constraints.clone()); } /** * Gets the constraints for the specified component. A copy of * the actual {@code GridBagConstraints} object is returned. * @param comp the component to be queried * @return the constraint for the specified component in this * grid bag layout; a copy of the actual constraint * object is returned */ public GridBagConstraints getConstraints(Component comp) { GridBagConstraints constraints = comptable.get(comp); if (constraints == null) { setConstraints(comp, defaultConstraints); constraints = comptable.get(comp); } return (GridBagConstraints) constraints.clone(); } /** * Retrieves the constraints for the specified component. * The return value is not a copy, but is the actual * {@code GridBagConstraints} object used by the layout mechanism. * <p> * If {@code comp} is not in the {@code GridBagLayout}, * a set of default {@code GridBagConstraints} are returned. * A {@code comp} value of {@code null} is invalid * and returns {@code null}. * * @param comp the component to be queried * @return the constraints for the specified component */ protected GridBagConstraints lookupConstraints(Component comp) { GridBagConstraints constraints = comptable.get(comp); if (constraints == null) { setConstraints(comp, defaultConstraints); constraints = comptable.get(comp); } return constraints; } /** * Removes the constraints for the specified component in this layout * @param comp the component to be modified */ private void removeConstraints(Component comp) { comptable.remove(comp); } /** * Determines the origin of the layout area, in the graphics coordinate * space of the target container. This value represents the pixel * coordinates of the top-left corner of the layout area regardless of * the {@code ComponentOrientation} value of the container. This * is distinct from the grid origin given by the cell coordinates (0,0). * Most applications do not call this method directly. * @return the graphics origin of the cell in the top-left * corner of the layout grid * @see java.awt.ComponentOrientation * @since 1.1 */ public Point getLayoutOrigin() { Point origin = new Point(0, 0); if (layoutInfo != null) { origin.x = layoutInfo.startx; origin.y = layoutInfo.starty; } return origin; } /** * Determines column widths and row heights for the layout grid. * <p> * Most applications do not call this method directly. * @return an array of two arrays, containing the widths * of the layout columns and * the heights of the layout rows * @since 1.1 */ public int[][] getLayoutDimensions() { if (layoutInfo == null) return new int[2][0]; int[][] dim = new int[2][]; dim[0] = new int[layoutInfo.width]; dim[1] = new int[layoutInfo.height]; System.arraycopy(layoutInfo.minWidth, 0, dim[0], 0, layoutInfo.width); System.arraycopy(layoutInfo.minHeight, 0, dim[1], 0, layoutInfo.height); return dim; } /** * Determines the weights of the layout grid's columns and rows. * Weights are used to calculate how much a given column or row * stretches beyond its preferred size, if the layout has extra * room to fill. * <p> * Most applications do not call this method directly. * @return an array of two arrays, representing the * horizontal weights of the layout columns * and the vertical weights of the layout rows * @since 1.1 */ public double[][] getLayoutWeights() { if (layoutInfo == null) return new double[2][0]; double[][] weights = new double[2][]; weights[0] = new double[layoutInfo.width]; weights[1] = new double[layoutInfo.height]; System.arraycopy(layoutInfo.weightX, 0, weights[0], 0, layoutInfo.width); System.arraycopy(layoutInfo.weightY, 0, weights[1], 0, layoutInfo.height); return weights; } /** * Determines which cell in the layout grid contains the point * specified by <code>(x, y)</code>. Each cell is identified * by its column index (ranging from 0 to the number of columns * minus 1) and its row index (ranging from 0 to the number of * rows minus 1). * <p> * If the <code>(x, y)</code> point lies * outside the grid, the following rules are used. * The column index is returned as zero if {@code x} lies to the * left of the layout for a left-to-right container or to the right of * the layout for a right-to-left container. The column index is returned * as the number of columns if {@code x} lies * to the right of the layout in a left-to-right container or to the left * in a right-to-left container. * The row index is returned as zero if {@code y} lies above the * layout, and as the number of rows if {@code y} lies * below the layout. The orientation of a container is determined by its * {@code ComponentOrientation} property. * @param x the <i>x</i> coordinate of a point * @param y the <i>y</i> coordinate of a point * @return an ordered pair of indexes that indicate which cell * in the layout grid contains the point * (<i>x</i>, <i>y</i>). * @see java.awt.ComponentOrientation * @since 1.1 */ public Point location(int x, int y) { Point loc = new Point(0, 0); int i, d; if (layoutInfo == null) return loc; d = layoutInfo.startx; if (!rightToLeft) { for (i = 0; i < layoutInfo.width; i++) { d += layoutInfo.minWidth[i]; if (d > x) break; } } else { for (i = layoutInfo.width - 1; i >= 0; i--) { if (d > x) break; d += layoutInfo.minWidth[i]; } i++; } loc.x = i; d = layoutInfo.starty; for (i = 0; i < layoutInfo.height; i++) { d += layoutInfo.minHeight[i]; if (d > y) break; } loc.y = i; return loc; } /** * Has no effect, since this layout manager does not use a per-component string. */ public void addLayoutComponent(String name, Component comp) { } /** * Adds the specified component to the layout, using the specified * {@code constraints} object. Note that constraints * are mutable and are, therefore, cloned when cached. * * @param comp the component to be added * @param constraints an object that determines how * the component is added to the layout * @exception IllegalArgumentException if {@code constraints} * is not a {@code GridBagConstraint} */ public void addLayoutComponent(Component comp, Object constraints) { if (constraints instanceof GridBagConstraints) { setConstraints(comp, (GridBagConstraints) constraints); } else if (constraints != null) { throw new IllegalArgumentException("cannot add to layout: constraints must be a GridBagConstraint"); } } /** * Removes the specified component from this layout. * <p> * Most applications do not call this method directly. * @param comp the component to be removed. * @see java.awt.Container#remove(java.awt.Component) * @see java.awt.Container#removeAll() */ public void removeLayoutComponent(Component comp) { removeConstraints(comp); } /** * Determines the preferred size of the {@code parent} * container using this grid bag layout. * <p> * Most applications do not call this method directly. * * @param parent the container in which to do the layout * @see java.awt.Container#getPreferredSize * @return the preferred size of the {@code parent} * container */ public Dimension preferredLayoutSize(Container parent) { GridBagLayoutInfo info = getLayoutInfo(parent, PREFERREDSIZE); return getMinSize(parent, info); } /** * Determines the minimum size of the {@code parent} container * using this grid bag layout. * <p> * Most applications do not call this method directly. * @param parent the container in which to do the layout * @see java.awt.Container#doLayout * @return the minimum size of the {@code parent} container */ public Dimension minimumLayoutSize(Container parent) { GridBagLayoutInfo info = getLayoutInfo(parent, MINSIZE); return getMinSize(parent, info); } /** * Returns the maximum dimensions for this layout given the components * in the specified target container. * @param target the container which needs to be laid out * @see Container * @see #minimumLayoutSize(Container) * @see #preferredLayoutSize(Container) * @return the maximum dimensions for this layout */ public Dimension maximumLayoutSize(Container target) { return new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE); } /** * 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. * * @return the value {@code 0.5f} to indicate centered */ public float getLayoutAlignmentX(Container parent) { return 0.5f; } /** * 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. * * @return the value {@code 0.5f} to indicate centered */ public float getLayoutAlignmentY(Container parent) { return 0.5f; } /** * Invalidates the layout, indicating that if the layout manager * has cached information it should be discarded. */ public void invalidateLayout(Container target) { } /** * Lays out the specified container using this grid bag layout. * This method reshapes components in the specified container in * order to satisfy the constraints of this {@code GridBagLayout} * object. * <p> * Most applications do not call this method directly. * @param parent the container in which to do the layout * @see java.awt.Container * @see java.awt.Container#doLayout */ public void layoutContainer(Container parent) { arrangeGrid(parent); } /** * Returns a string representation of this grid bag layout's values. * @return a string representation of this grid bag layout. */ public String toString() { return getClass().getName(); } /** * Print the layout information. Useful for debugging. */ /* DEBUG * * protected void dumpLayoutInfo(GridBagLayoutInfo s) { * int x; * * System.out.println("Col\tWidth\tWeight"); * for (x=0; x<s.width; x++) { * System.out.println(x + "\t" + * s.minWidth[x] + "\t" + * s.weightX[x]); * } * System.out.println("Row\tHeight\tWeight"); * for (x=0; x<s.height; x++) { * System.out.println(x + "\t" + * s.minHeight[x] + "\t" + * s.weightY[x]); * } * } */ /** * Print the layout constraints. Useful for debugging. */ /* DEBUG * * protected void dumpConstraints(GridBagConstraints constraints) { * System.out.println( * "wt " + * constraints.weightx + * " " + * constraints.weighty + * ", " + * * "box " + * constraints.gridx + * " " + * constraints.gridy + * " " + * constraints.gridwidth + * " " + * constraints.gridheight + * ", " + * * "min " + * constraints.minWidth + * " " + * constraints.minHeight + * ", " + * * "pad " + * constraints.insets.bottom + * " " + * constraints.insets.left + * " " + * constraints.insets.right + * " " + * constraints.insets.top + * " " + * constraints.ipadx + * " " + * constraints.ipady); * } */ /** * Fills in an instance of {@code GridBagLayoutInfo} for the * current set of managed children. This requires three passes through the * set of children: * * <ol> * <li>Figure out the dimensions of the layout grid. * <li>Determine which cells the components occupy. * <li>Distribute the weights and min sizes among the rows/columns. * </ol> * * This also caches the minsizes for all the children when they are * first encountered (so subsequent loops don't need to ask again). * <p> * This method should only be used internally by * {@code GridBagLayout}. * * @param parent the layout container * @param sizeflag either {@code PREFERREDSIZE} or * {@code MINSIZE} * @return the {@code GridBagLayoutInfo} for the set of children * @since 1.4 */ protected GridBagLayoutInfo getLayoutInfo(Container parent, int sizeflag) { return GetLayoutInfo(parent, sizeflag); } /* * Calculate maximum array sizes to allocate arrays without ensureCapacity * we may use preCalculated sizes in whole class because of upper estimation of * maximumArrayXIndex and maximumArrayYIndex. */ private long[] preInitMaximumArraySizes(Container parent) { Component[] components = parent.getComponents(); Component comp; GridBagConstraints constraints; int curX, curY; int curWidth, curHeight; int preMaximumArrayXIndex = 0; int preMaximumArrayYIndex = 0; long[] returnArray = new long[2]; for (int compId = 0; compId < components.length; compId++) { comp = components[compId]; if (!comp.isVisible()) { continue; } constraints = lookupConstraints(comp); curX = constraints.gridx; curY = constraints.gridy; curWidth = constraints.gridwidth; curHeight = constraints.gridheight; // -1==RELATIVE, means that column|row equals to previously added component, // since each next Component with gridx|gridy == RELATIVE starts from // previous position, so we should start from previous component which // already used in maximumArray[X|Y]Index calculation. We could just increase // maximum by 1 to handle situation when component with gridx=-1 was added. if (curX < 0) { curX = ++preMaximumArrayYIndex; } if (curY < 0) { curY = ++preMaximumArrayXIndex; } // gridwidth|gridheight may be equal to RELATIVE (-1) or REMAINDER (0) // in any case using 1 instead of 0 or -1 should be sufficient to for // correct maximumArraySizes calculation if (curWidth <= 0) { curWidth = 1; } if (curHeight <= 0) { curHeight = 1; } preMaximumArrayXIndex = Math.max(curY + curHeight, preMaximumArrayXIndex); preMaximumArrayYIndex = Math.max(curX + curWidth, preMaximumArrayYIndex); } //for (components) loop // Must specify index++ to allocate well-working arrays. /* fix for 4623196. * now return long array instead of Point */ returnArray[0] = preMaximumArrayXIndex; returnArray[1] = preMaximumArrayYIndex; return returnArray; } //PreInitMaximumSizes /** * This method is obsolete and supplied for backwards * compatibility only; new code should call {@link * #getLayoutInfo(java.awt.Container, int) getLayoutInfo} instead. * * Fills in an instance of {@code GridBagLayoutInfo} for the * current set of managed children. This method is the same * as {@code getLayoutInfo}; refer to {@code getLayoutInfo} * description for details. * * @param parent the layout container * @param sizeflag either {@code PREFERREDSIZE} or {@code MINSIZE} * @return the {@code GridBagLayoutInfo} for the set of children */ protected GridBagLayoutInfo GetLayoutInfo(Container parent, int sizeflag) { synchronized (parent.getTreeLock()) { GridBagLayoutInfo r; Component comp; GridBagConstraints constraints; Dimension d; Component[] components = parent.getComponents(); // Code below will address index curX+curWidth in the case of yMaxArray, weightY // ( respectively curY+curHeight for xMaxArray, weightX ) where // curX in 0 to preInitMaximumArraySizes.y // Thus, the maximum index that could // be calculated in the following code is curX+curX. // EmpericMultier equals 2 because of this. int layoutWidth, layoutHeight; int[] xMaxArray; int[] yMaxArray; int compindex, i, k, px, py, pixels_diff, nextSize; int curX = 0; // constraints.gridx int curY = 0; // constraints.gridy int curWidth = 1; // constraints.gridwidth int curHeight = 1; // constraints.gridheight int curRow, curCol; double weight_diff, weight; int maximumArrayXIndex = 0; int maximumArrayYIndex = 0; int anchor; /* * Pass #1 * * Figure out the dimensions of the layout grid (use a value of 1 for * zero or negative widths and heights). */ layoutWidth = layoutHeight = 0; curRow = curCol = -1; long[] arraySizes = preInitMaximumArraySizes(parent); /* fix for 4623196. * If user try to create a very big grid we can * get NegativeArraySizeException because of integer value * overflow (EMPIRICMULTIPLIER*gridSize might be more then Integer.MAX_VALUE). * We need to detect this situation and try to create a * grid with Integer.MAX_VALUE size instead. */ maximumArrayXIndex = (EMPIRICMULTIPLIER * arraySizes[0] > Integer.MAX_VALUE) ? Integer.MAX_VALUE : EMPIRICMULTIPLIER * (int) arraySizes[0]; maximumArrayYIndex = (EMPIRICMULTIPLIER * arraySizes[1] > Integer.MAX_VALUE) ? Integer.MAX_VALUE : EMPIRICMULTIPLIER * (int) arraySizes[1]; if (rowHeights != null) { maximumArrayXIndex = Math.max(maximumArrayXIndex, rowHeights.length); } if (columnWidths != null) { maximumArrayYIndex = Math.max(maximumArrayYIndex, columnWidths.length); } xMaxArray = new int[maximumArrayXIndex]; yMaxArray = new int[maximumArrayYIndex]; boolean hasBaseline = false; for (compindex = 0; compindex < components.length; compindex++) { comp = components[compindex]; if (!comp.isVisible()) continue; constraints = lookupConstraints(comp); curX = constraints.gridx; curY = constraints.gridy; curWidth = constraints.gridwidth; if (curWidth <= 0) curWidth = 1; curHeight = constraints.gridheight; if (curHeight <= 0) curHeight = 1; /* If x or y is negative, then use relative positioning: */ if (curX < 0 && curY < 0) { if (curRow >= 0) curY = curRow; else if (curCol >= 0) curX = curCol; else curY = 0; } if (curX < 0) { px = 0; for (i = curY; i < (curY + curHeight); i++) { px = Math.max(px, xMaxArray[i]); } curX = px - curX - 1; if (curX < 0) curX = 0; } else if (curY < 0) { py = 0; for (i = curX; i < (curX + curWidth); i++) { py = Math.max(py, yMaxArray[i]); } curY = py - curY - 1; if (curY < 0) curY = 0; } /* Adjust the grid width and height * fix for 5005945: unnecessary loops removed */ px = curX + curWidth; if (layoutWidth < px) { layoutWidth = px; } py = curY + curHeight; if (layoutHeight < py) { layoutHeight = py; } /* Adjust xMaxArray and yMaxArray */ for (i = curX; i < (curX + curWidth); i++) { yMaxArray[i] = py; } for (i = curY; i < (curY + curHeight); i++) { xMaxArray[i] = px; } /* Cache the current slave's size. */ if (sizeflag == PREFERREDSIZE) d = comp.getPreferredSize(); else d = comp.getMinimumSize(); constraints.minWidth = d.width; constraints.minHeight = d.height; if (calculateBaseline(comp, constraints, d)) { hasBaseline = true; } /* Zero width and height must mean that this is the last item (or * else something is wrong). */ if (constraints.gridheight == 0 && constraints.gridwidth == 0) curRow = curCol = -1; /* Zero width starts a new row */ if (constraints.gridheight == 0 && curRow < 0) curCol = curX + curWidth; /* Zero height starts a new column */ else if (constraints.gridwidth == 0 && curCol < 0) curRow = curY + curHeight; } //for (components) loop /* * Apply minimum row/column dimensions */ if (columnWidths != null && layoutWidth < columnWidths.length) layoutWidth = columnWidths.length; if (rowHeights != null && layoutHeight < rowHeights.length) layoutHeight = rowHeights.length; r = new GridBagLayoutInfo(layoutWidth, layoutHeight); /* * Pass #2 * * Negative values for gridX are filled in with the current x value. * Negative values for gridY are filled in with the current y value. * Negative or zero values for gridWidth and gridHeight end the current * row or column, respectively. */ curRow = curCol = -1; Arrays.fill(xMaxArray, 0); Arrays.fill(yMaxArray, 0); int[] maxAscent = null; int[] maxDescent = null; short[] baselineType = null; if (hasBaseline) { r.maxAscent = maxAscent = new int[layoutHeight]; r.maxDescent = maxDescent = new int[layoutHeight]; r.baselineType = baselineType = new short[layoutHeight]; r.hasBaseline = true; } for (compindex = 0; compindex < components.length; compindex++) { comp = components[compindex]; if (!comp.isVisible()) continue; constraints = lookupConstraints(comp); curX = constraints.gridx; curY = constraints.gridy; curWidth = constraints.gridwidth; curHeight = constraints.gridheight; /* If x or y is negative, then use relative positioning: */ if (curX < 0 && curY < 0) { if (curRow >= 0) curY = curRow; else if (curCol >= 0) curX = curCol; else curY = 0; } if (curX < 0) { if (curHeight <= 0) { curHeight += r.height - curY; if (curHeight < 1) curHeight = 1; } px = 0; for (i = curY; i < (curY + curHeight); i++) px = Math.max(px, xMaxArray[i]); curX = px - curX - 1; if (curX < 0) curX = 0; } else if (curY < 0) { if (curWidth <= 0) { curWidth += r.width - curX; if (curWidth < 1) curWidth = 1; } py = 0; for (i = curX; i < (curX + curWidth); i++) { py = Math.max(py, yMaxArray[i]); } curY = py - curY - 1; if (curY < 0) curY = 0; } if (curWidth <= 0) { curWidth += r.width - curX; if (curWidth < 1) curWidth = 1; } if (curHeight <= 0) { curHeight += r.height - curY; if (curHeight < 1) curHeight = 1; } px = curX + curWidth; py = curY + curHeight; for (i = curX; i < (curX + curWidth); i++) { yMaxArray[i] = py; } for (i = curY; i < (curY + curHeight); i++) { xMaxArray[i] = px; } /* Make negative sizes start a new row/column */ if (constraints.gridheight == 0 && constraints.gridwidth == 0) curRow = curCol = -1; if (constraints.gridheight == 0 && curRow < 0) curCol = curX + curWidth; else if (constraints.gridwidth == 0 && curCol < 0) curRow = curY + curHeight; /* Assign the new values to the gridbag slave */ constraints.tempX = curX; constraints.tempY = curY; constraints.tempWidth = curWidth; constraints.tempHeight = curHeight; anchor = constraints.anchor; if (hasBaseline) { switch (anchor) { case GridBagConstraints.BASELINE: case GridBagConstraints.BASELINE_LEADING: case GridBagConstraints.BASELINE_TRAILING: if (constraints.ascent >= 0) { if (curHeight == 1) { maxAscent[curY] = Math.max(maxAscent[curY], constraints.ascent); maxDescent[curY] = Math.max(maxDescent[curY], constraints.descent); } else { if (constraints.baselineResizeBehavior == Component.BaselineResizeBehavior.CONSTANT_DESCENT) { maxDescent[curY + curHeight - 1] = Math.max(maxDescent[curY + curHeight - 1], constraints.descent); } else { maxAscent[curY] = Math.max(maxAscent[curY], constraints.ascent); } } if (constraints.baselineResizeBehavior == Component.BaselineResizeBehavior.CONSTANT_DESCENT) { baselineType[curY + curHeight - 1] |= (1 << constraints.baselineResizeBehavior.ordinal()); } else { baselineType[curY] |= (1 << constraints.baselineResizeBehavior.ordinal()); } } break; case GridBagConstraints.ABOVE_BASELINE: case GridBagConstraints.ABOVE_BASELINE_LEADING: case GridBagConstraints.ABOVE_BASELINE_TRAILING: // Component positioned above the baseline. // To make the bottom edge of the component aligned // with the baseline the bottom inset is // added to the descent, the rest to the ascent. pixels_diff = constraints.minHeight + constraints.insets.top + constraints.ipady; maxAscent[curY] = Math.max(maxAscent[curY], pixels_diff); maxDescent[curY] = Math.max(maxDescent[curY], constraints.insets.bottom); break; case GridBagConstraints.BELOW_BASELINE: case GridBagConstraints.BELOW_BASELINE_LEADING: case GridBagConstraints.BELOW_BASELINE_TRAILING: // Component positioned below the baseline. // To make the top edge of the component aligned // with the baseline the top inset is // added to the ascent, the rest to the descent. pixels_diff = constraints.minHeight + constraints.insets.bottom + constraints.ipady; maxDescent[curY] = Math.max(maxDescent[curY], pixels_diff); maxAscent[curY] = Math.max(maxAscent[curY], constraints.insets.top); break; } } } r.weightX = new double[maximumArrayYIndex]; r.weightY = new double[maximumArrayXIndex]; r.minWidth = new int[maximumArrayYIndex]; r.minHeight = new int[maximumArrayXIndex]; /* * Apply minimum row/column dimensions and weights */ if (columnWidths != null) System.arraycopy(columnWidths, 0, r.minWidth, 0, columnWidths.length); if (rowHeights != null) System.arraycopy(rowHeights, 0, r.minHeight, 0, rowHeights.length); if (columnWeights != null) System.arraycopy(columnWeights, 0, r.weightX, 0, Math.min(r.weightX.length, columnWeights.length)); if (rowWeights != null) System.arraycopy(rowWeights, 0, r.weightY, 0, Math.min(r.weightY.length, rowWeights.length)); /* * Pass #3 * * Distribute the minimum widths and weights: */ nextSize = Integer.MAX_VALUE; for (i = 1; i != Integer.MAX_VALUE; i = nextSize, nextSize = Integer.MAX_VALUE) { for (compindex = 0; compindex < components.length; compindex++) { comp = components[compindex]; if (!comp.isVisible()) continue; constraints = lookupConstraints(comp); if (constraints.tempWidth == i) { px = constraints.tempX + constraints.tempWidth; /* right column */ /* * Figure out if we should use this slave\'s weight. If the weight * is less than the total weight spanned by the width of the cell, * then discard the weight. Otherwise split the difference * according to the existing weights. */ weight_diff = constraints.weightx; for (k = constraints.tempX; k < px; k++) weight_diff -= r.weightX[k]; if (weight_diff > 0.0) { weight = 0.0; for (k = constraints.tempX; k < px; k++) weight += r.weightX[k]; for (k = constraints.tempX; weight > 0.0 && k < px; k++) { double wt = r.weightX[k]; double dx = (wt * weight_diff) / weight; r.weightX[k] += dx; weight_diff -= dx; weight -= wt; } /* Assign the remainder to the rightmost cell */ r.weightX[px - 1] += weight_diff; } /* * Calculate the minWidth array values. * First, figure out how wide the current slave needs to be. * Then, see if it will fit within the current minWidth values. * If it will not fit, add the difference according to the * weightX array. */ pixels_diff = constraints.minWidth + constraints.ipadx + constraints.insets.left + constraints.insets.right; for (k = constraints.tempX; k < px; k++) pixels_diff -= r.minWidth[k]; if (pixels_diff > 0) { weight = 0.0; for (k = constraints.tempX; k < px; k++) weight += r.weightX[k]; for (k = constraints.tempX; weight > 0.0 && k < px; k++) { double wt = r.weightX[k]; int dx = (int) ((wt * ((double) pixels_diff)) / weight); r.minWidth[k] += dx; pixels_diff -= dx; weight -= wt; } /* Any leftovers go into the rightmost cell */ r.minWidth[px - 1] += pixels_diff; } } else if (constraints.tempWidth > i && constraints.tempWidth < nextSize) nextSize = constraints.tempWidth; if (constraints.tempHeight == i) { py = constraints.tempY + constraints.tempHeight; /* bottom row */ /* * Figure out if we should use this slave's weight. If the weight * is less than the total weight spanned by the height of the cell, * then discard the weight. Otherwise split it the difference * according to the existing weights. */ weight_diff = constraints.weighty; for (k = constraints.tempY; k < py; k++) weight_diff -= r.weightY[k]; if (weight_diff > 0.0) { weight = 0.0; for (k = constraints.tempY; k < py; k++) weight += r.weightY[k]; for (k = constraints.tempY; weight > 0.0 && k < py; k++) { double wt = r.weightY[k]; double dy = (wt * weight_diff) / weight; r.weightY[k] += dy; weight_diff -= dy; weight -= wt; } /* Assign the remainder to the bottom cell */ r.weightY[py - 1] += weight_diff; } /* * Calculate the minHeight array values. * First, figure out how tall the current slave needs to be. * Then, see if it will fit within the current minHeight values. * If it will not fit, add the difference according to the * weightY array. */ pixels_diff = -1; if (hasBaseline) { switch (constraints.anchor) { case GridBagConstraints.BASELINE: case GridBagConstraints.BASELINE_LEADING: case GridBagConstraints.BASELINE_TRAILING: if (constraints.ascent >= 0) { if (constraints.tempHeight == 1) { pixels_diff = maxAscent[constraints.tempY] + maxDescent[constraints.tempY]; } else if (constraints.baselineResizeBehavior != Component.BaselineResizeBehavior.CONSTANT_DESCENT) { pixels_diff = maxAscent[constraints.tempY] + constraints.descent; } else { pixels_diff = constraints.ascent + maxDescent[constraints.tempY + constraints.tempHeight - 1]; } } break; case GridBagConstraints.ABOVE_BASELINE: case GridBagConstraints.ABOVE_BASELINE_LEADING: case GridBagConstraints.ABOVE_BASELINE_TRAILING: pixels_diff = constraints.insets.top + constraints.minHeight + constraints.ipady + maxDescent[constraints.tempY]; break; case GridBagConstraints.BELOW_BASELINE: case GridBagConstraints.BELOW_BASELINE_LEADING: case GridBagConstraints.BELOW_BASELINE_TRAILING: pixels_diff = maxAscent[constraints.tempY] + constraints.minHeight + constraints.insets.bottom + constraints.ipady; break; } } if (pixels_diff == -1) { pixels_diff = constraints.minHeight + constraints.ipady + constraints.insets.top + constraints.insets.bottom; } for (k = constraints.tempY; k < py; k++) pixels_diff -= r.minHeight[k]; if (pixels_diff > 0) { weight = 0.0; for (k = constraints.tempY; k < py; k++) weight += r.weightY[k]; for (k = constraints.tempY; weight > 0.0 && k < py; k++) { double wt = r.weightY[k]; int dy = (int) ((wt * ((double) pixels_diff)) / weight); r.minHeight[k] += dy; pixels_diff -= dy; weight -= wt; } /* Any leftovers go into the bottom cell */ r.minHeight[py - 1] += pixels_diff; } } else if (constraints.tempHeight > i && constraints.tempHeight < nextSize) nextSize = constraints.tempHeight; } } return r; } } //getLayoutInfo() /** * Calculate the baseline for the specified component. * If {@code c} is positioned along it's baseline, the baseline is * obtained and the {@code constraints} ascent, descent and * baseline resize behavior are set from the component; and true is * returned. Otherwise false is returned. */ private boolean calculateBaseline(Component c, GridBagConstraints constraints, Dimension size) { int anchor = constraints.anchor; if (anchor == GridBagConstraints.BASELINE || anchor == GridBagConstraints.BASELINE_LEADING || anchor == GridBagConstraints.BASELINE_TRAILING) { // Apply the padding to the component, then ask for the baseline. int w = size.width + constraints.ipadx; int h = size.height + constraints.ipady; constraints.ascent = c.getBaseline(w, h); if (constraints.ascent >= 0) { // Component has a baseline int baseline = constraints.ascent; // Adjust the ascent and descent to include the insets. constraints.descent = h - constraints.ascent + constraints.insets.bottom; constraints.ascent += constraints.insets.top; constraints.baselineResizeBehavior = c.getBaselineResizeBehavior(); constraints.centerPadding = 0; if (constraints.baselineResizeBehavior == Component.BaselineResizeBehavior.CENTER_OFFSET) { // Component has a baseline resize behavior of // CENTER_OFFSET, calculate centerPadding and // centerOffset (see the description of // CENTER_OFFSET in the enum for details on this // algorithm). int nextBaseline = c.getBaseline(w, h + 1); constraints.centerOffset = baseline - h / 2; if (h % 2 == 0) { if (baseline != nextBaseline) { constraints.centerPadding = 1; } } else if (baseline == nextBaseline) { constraints.centerOffset--; constraints.centerPadding = 1; } } } return true; } else { constraints.ascent = -1; return false; } } /** * Adjusts the x, y, width, and height fields to the correct * values depending on the constraint geometry and pads. * This method should only be used internally by * {@code GridBagLayout}. * * @param constraints the constraints to be applied * @param r the {@code Rectangle} to be adjusted * @since 1.4 */ protected void adjustForGravity(GridBagConstraints constraints, Rectangle r) { AdjustForGravity(constraints, r); } /** * Adjusts the x, y, width, and height fields to the correct * values depending on the constraint geometry and pads. * <p> * This method is obsolete and supplied for backwards * compatibility only; new code should call {@link * #adjustForGravity(java.awt.GridBagConstraints, java.awt.Rectangle) * adjustForGravity} instead. * This method is the same as {@code adjustForGravity} * * @param constraints the constraints to be applied * @param r the {@code Rectangle} to be adjusted */ protected void AdjustForGravity(GridBagConstraints constraints, Rectangle r) { int diffx, diffy; int cellY = r.y; int cellHeight = r.height; if (!rightToLeft) { r.x += constraints.insets.left; } else { r.x -= r.width - constraints.insets.right; } r.width -= (constraints.insets.left + constraints.insets.right); r.y += constraints.insets.top; r.height -= (constraints.insets.top + constraints.insets.bottom); diffx = 0; if ((constraints.fill != GridBagConstraints.HORIZONTAL && constraints.fill != GridBagConstraints.BOTH) && (r.width > (constraints.minWidth + constraints.ipadx))) { diffx = r.width - (constraints.minWidth + constraints.ipadx); r.width = constraints.minWidth + constraints.ipadx; } diffy = 0; if ((constraints.fill != GridBagConstraints.VERTICAL && constraints.fill != GridBagConstraints.BOTH) && (r.height > (constraints.minHeight + constraints.ipady))) { diffy = r.height - (constraints.minHeight + constraints.ipady); r.height = constraints.minHeight + constraints.ipady; } switch (constraints.anchor) { case GridBagConstraints.BASELINE: r.x += diffx / 2; alignOnBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.BASELINE_LEADING: if (rightToLeft) { r.x += diffx; } alignOnBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.BASELINE_TRAILING: if (!rightToLeft) { r.x += diffx; } alignOnBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.ABOVE_BASELINE: r.x += diffx / 2; alignAboveBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.ABOVE_BASELINE_LEADING: if (rightToLeft) { r.x += diffx; } alignAboveBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.ABOVE_BASELINE_TRAILING: if (!rightToLeft) { r.x += diffx; } alignAboveBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.BELOW_BASELINE: r.x += diffx / 2; alignBelowBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.BELOW_BASELINE_LEADING: if (rightToLeft) { r.x += diffx; } alignBelowBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.BELOW_BASELINE_TRAILING: if (!rightToLeft) { r.x += diffx; } alignBelowBaseline(constraints, r, cellY, cellHeight); break; case GridBagConstraints.CENTER: r.x += diffx / 2; r.y += diffy / 2; break; case GridBagConstraints.PAGE_START: case GridBagConstraints.NORTH: r.x += diffx / 2; break; case GridBagConstraints.NORTHEAST: r.x += diffx; break; case GridBagConstraints.EAST: r.x += diffx; r.y += diffy / 2; break; case GridBagConstraints.SOUTHEAST: r.x += diffx; r.y += diffy; break; case GridBagConstraints.PAGE_END: case GridBagConstraints.SOUTH: r.x += diffx / 2; r.y += diffy; break; case GridBagConstraints.SOUTHWEST: r.y += diffy; break; case GridBagConstraints.WEST: r.y += diffy / 2; break; case GridBagConstraints.NORTHWEST: break; case GridBagConstraints.LINE_START: if (rightToLeft) { r.x += diffx; } r.y += diffy / 2; break; case GridBagConstraints.LINE_END: if (!rightToLeft) { r.x += diffx; } r.y += diffy / 2; break; case GridBagConstraints.FIRST_LINE_START: if (rightToLeft) { r.x += diffx; } break; case GridBagConstraints.FIRST_LINE_END: if (!rightToLeft) { r.x += diffx; } break; case GridBagConstraints.LAST_LINE_START: if (rightToLeft) { r.x += diffx; } r.y += diffy; break; case GridBagConstraints.LAST_LINE_END: if (!rightToLeft) { r.x += diffx; } r.y += diffy; break; default: throw new IllegalArgumentException("illegal anchor value"); } } /** * Positions on the baseline. * * @param cellY the location of the row, does not include insets * @param cellHeight the height of the row, does not take into account * insets * @param r available bounds for the component, is padded by insets and * ipady */ private void alignOnBaseline(GridBagConstraints cons, Rectangle r, int cellY, int cellHeight) { if (cons.ascent >= 0) { if (cons.baselineResizeBehavior == Component.BaselineResizeBehavior.CONSTANT_DESCENT) { // Anchor to the bottom. // Baseline is at (cellY + cellHeight - maxDescent). // Bottom of component (maxY) is at baseline + descent // of component. We need to subtract the bottom inset here // as the descent in the constraints object includes the // bottom inset. int maxY = cellY + cellHeight - layoutInfo.maxDescent[cons.tempY + cons.tempHeight - 1] + cons.descent - cons.insets.bottom; if (!cons.isVerticallyResizable()) { // Component not resizable, calculate y location // from maxY - height. r.y = maxY - cons.minHeight; r.height = cons.minHeight; } else { // Component is resizable. As brb is constant descent, // can expand component to fill region above baseline. // Subtract out the top inset so that components insets // are honored. r.height = maxY - cellY - cons.insets.top; } } else { // BRB is not constant_descent int baseline; // baseline for the row, relative to cellY // Component baseline, includes insets.top int ascent = cons.ascent; if (layoutInfo.hasConstantDescent(cons.tempY)) { // Mixed ascent/descent in same row, calculate position // off maxDescent baseline = cellHeight - layoutInfo.maxDescent[cons.tempY]; } else { // Only ascents/unknown in this row, anchor to top baseline = layoutInfo.maxAscent[cons.tempY]; } if (cons.baselineResizeBehavior == Component.BaselineResizeBehavior.OTHER) { // BRB is other, which means we can only determine // the baseline by asking for it again giving the // size we plan on using for the component. boolean fits = false; ascent = componentAdjusting.getBaseline(r.width, r.height); if (ascent >= 0) { // Component has a baseline, pad with top inset // (this follows from calculateBaseline which // does the same). ascent += cons.insets.top; } if (ascent >= 0 && ascent <= baseline) { // Components baseline fits within rows baseline. // Make sure the descent fits within the space as well. if (baseline + (r.height - ascent - cons.insets.top) <= cellHeight - cons.insets.bottom) { // It fits, we're good. fits = true; } else if (cons.isVerticallyResizable()) { // Doesn't fit, but it's resizable. Try // again assuming we'll get ascent again. int ascent2 = componentAdjusting.getBaseline(r.width, cellHeight - cons.insets.bottom - baseline + ascent); if (ascent2 >= 0) { ascent2 += cons.insets.top; } if (ascent2 >= 0 && ascent2 <= ascent) { // It'll fit r.height = cellHeight - cons.insets.bottom - baseline + ascent; ascent = ascent2; fits = true; } } } if (!fits) { // Doesn't fit, use min size and original ascent ascent = cons.ascent; r.width = cons.minWidth; r.height = cons.minHeight; } } // Reset the components y location based on // components ascent and baseline for row. Because ascent // includes the baseline r.y = cellY + baseline - ascent + cons.insets.top; if (cons.isVerticallyResizable()) { switch (cons.baselineResizeBehavior) { case CONSTANT_ASCENT: r.height = Math.max(cons.minHeight, cellY + cellHeight - r.y - cons.insets.bottom); break; case CENTER_OFFSET: { int upper = r.y - cellY - cons.insets.top; int lower = cellY + cellHeight - r.y - cons.minHeight - cons.insets.bottom; int delta = Math.min(upper, lower); delta += delta; if (delta > 0 && (cons.minHeight + cons.centerPadding + delta) / 2 + cons.centerOffset != baseline) { // Off by 1 delta--; } r.height = cons.minHeight + delta; r.y = cellY + baseline - (r.height + cons.centerPadding) / 2 - cons.centerOffset; } break; case OTHER: // Handled above break; default: break; } } } } else { centerVertically(cons, r, cellHeight); } } /** * Positions the specified component above the baseline. That is * the bottom edge of the component will be aligned along the baseline. * If the row does not have a baseline, this centers the component. */ private void alignAboveBaseline(GridBagConstraints cons, Rectangle r, int cellY, int cellHeight) { if (layoutInfo.hasBaseline(cons.tempY)) { int maxY; // Baseline for the row if (layoutInfo.hasConstantDescent(cons.tempY)) { // Prefer descent maxY = cellY + cellHeight - layoutInfo.maxDescent[cons.tempY]; } else { // Prefer ascent maxY = cellY + layoutInfo.maxAscent[cons.tempY]; } if (cons.isVerticallyResizable()) { // Component is resizable. Top edge is offset by top // inset, bottom edge on baseline. r.y = cellY + cons.insets.top; r.height = maxY - r.y; } else { // Not resizable. r.height = cons.minHeight + cons.ipady; r.y = maxY - r.height; } } else { centerVertically(cons, r, cellHeight); } } /** * Positions below the baseline. */ private void alignBelowBaseline(GridBagConstraints cons, Rectangle r, int cellY, int cellHeight) { if (layoutInfo.hasBaseline(cons.tempY)) { if (layoutInfo.hasConstantDescent(cons.tempY)) { // Prefer descent r.y = cellY + cellHeight - layoutInfo.maxDescent[cons.tempY]; } else { // Prefer ascent r.y = cellY + layoutInfo.maxAscent[cons.tempY]; } if (cons.isVerticallyResizable()) { r.height = cellY + cellHeight - r.y - cons.insets.bottom; } } else { centerVertically(cons, r, cellHeight); } } private void centerVertically(GridBagConstraints cons, Rectangle r, int cellHeight) { if (!cons.isVerticallyResizable()) { r.y += Math.max(0, (cellHeight - cons.insets.top - cons.insets.bottom - cons.minHeight - cons.ipady) / 2); } } /** * Figures out the minimum size of the * master based on the information from {@code getLayoutInfo}. * This method should only be used internally by * {@code GridBagLayout}. * * @param parent the layout container * @param info the layout info for this parent * @return a {@code Dimension} object containing the * minimum size * @since 1.4 */ protected Dimension getMinSize(Container parent, GridBagLayoutInfo info) { return GetMinSize(parent, info); } /** * This method is obsolete and supplied for backwards * compatibility only; new code should call {@link * #getMinSize(java.awt.Container, GridBagLayoutInfo) getMinSize} instead. * This method is the same as {@code getMinSize} * * @param parent the layout container * @param info the layout info for this parent * @return a {@code Dimension} object containing the * minimum size */ protected Dimension GetMinSize(Container parent, GridBagLayoutInfo info) { Dimension d = new Dimension(); int i, t; Insets insets = parent.getInsets(); t = 0; for (i = 0; i < info.width; i++) t += info.minWidth[i]; d.width = t + insets.left + insets.right; t = 0; for (i = 0; i < info.height; i++) t += info.minHeight[i]; d.height = t + insets.top + insets.bottom; return d; } transient boolean rightToLeft = false; /** * Lays out the grid. * This method should only be used internally by * {@code GridBagLayout}. * * @param parent the layout container * @since 1.4 */ protected void arrangeGrid(Container parent) { ArrangeGrid(parent); } /** * This method is obsolete and supplied for backwards * compatibility only; new code should call {@link * #arrangeGrid(Container) arrangeGrid} instead. * This method is the same as {@code arrangeGrid} * * @param parent the layout container */ protected void ArrangeGrid(Container parent) { Component comp; int compindex; GridBagConstraints constraints; Insets insets = parent.getInsets(); Component[] components = parent.getComponents(); Dimension d; Rectangle r = new Rectangle(); int i, diffw, diffh; double weight; GridBagLayoutInfo info; rightToLeft = !parent.getComponentOrientation().isLeftToRight(); /* * If the parent has no slaves anymore, then don't do anything * at all: just leave the parent's size as-is. */ if (components.length == 0 && (columnWidths == null || columnWidths.length == 0) && (rowHeights == null || rowHeights.length == 0)) { return; } /* * Pass #1: scan all the slaves to figure out the total amount * of space needed. */ info = getLayoutInfo(parent, PREFERREDSIZE); d = getMinSize(parent, info); if (parent.width < d.width || parent.height < d.height) { info = getLayoutInfo(parent, MINSIZE); d = getMinSize(parent, info); } layoutInfo = info; r.width = d.width; r.height = d.height; /* * DEBUG * * DumpLayoutInfo(info); * for (compindex = 0 ; compindex < components.length ; compindex++) { * comp = components[compindex]; * if (!comp.isVisible()) * continue; * constraints = lookupConstraints(comp); * DumpConstraints(constraints); * } * System.out.println("minSize " + r.width + " " + r.height); */ /* * If the current dimensions of the window don't match the desired * dimensions, then adjust the minWidth and minHeight arrays * according to the weights. */ diffw = parent.width - r.width; if (diffw != 0) { weight = 0.0; for (i = 0; i < info.width; i++) weight += info.weightX[i]; if (weight > 0.0) { for (i = 0; i < info.width; i++) { int dx = (int) ((((double) diffw) * info.weightX[i]) / weight); info.minWidth[i] += dx; r.width += dx; if (info.minWidth[i] < 0) { r.width -= info.minWidth[i]; info.minWidth[i] = 0; } } } diffw = parent.width - r.width; } else { diffw = 0; } diffh = parent.height - r.height; if (diffh != 0) { weight = 0.0; for (i = 0; i < info.height; i++) weight += info.weightY[i]; if (weight > 0.0) { for (i = 0; i < info.height; i++) { int dy = (int) ((((double) diffh) * info.weightY[i]) / weight); info.minHeight[i] += dy; r.height += dy; if (info.minHeight[i] < 0) { r.height -= info.minHeight[i]; info.minHeight[i] = 0; } } } diffh = parent.height - r.height; } else { diffh = 0; } /* * DEBUG * * System.out.println("Re-adjusted:"); * DumpLayoutInfo(info); */ /* * Now do the actual layout of the slaves using the layout information * that has been collected. */ info.startx = diffw / 2 + insets.left; info.starty = diffh / 2 + insets.top; for (compindex = 0; compindex < components.length; compindex++) { comp = components[compindex]; if (!comp.isVisible()) { continue; } constraints = lookupConstraints(comp); if (!rightToLeft) { r.x = info.startx; for (i = 0; i < constraints.tempX; i++) r.x += info.minWidth[i]; } else { r.x = parent.width - (diffw / 2 + insets.right); for (i = 0; i < constraints.tempX; i++) r.x -= info.minWidth[i]; } r.y = info.starty; for (i = 0; i < constraints.tempY; i++) r.y += info.minHeight[i]; r.width = 0; for (i = constraints.tempX; i < (constraints.tempX + constraints.tempWidth); i++) { r.width += info.minWidth[i]; } r.height = 0; for (i = constraints.tempY; i < (constraints.tempY + constraints.tempHeight); i++) { r.height += info.minHeight[i]; } componentAdjusting = comp; adjustForGravity(constraints, r); /* fix for 4408108 - components were being created outside of the container */ /* fix for 4969409 "-" replaced by "+" */ if (r.x < 0) { r.width += r.x; r.x = 0; } if (r.y < 0) { r.height += r.y; r.y = 0; } /* * If the window is too small to be interesting then * unmap it. Otherwise configure it and then make sure * it's mapped. */ if ((r.width <= 0) || (r.height <= 0)) { comp.setBounds(0, 0, 0, 0); } else { if (comp.x != r.x || comp.y != r.y || comp.width != r.width || comp.height != r.height) { comp.setBounds(r.x, r.y, r.width, r.height); } } } } // Added for serial backwards compatibility (4348425) static final long serialVersionUID = 8838754796412211005L; }