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Diffstat (limited to 'libjava/classpath/javax/swing/BoxLayout.java')
| -rw-r--r-- | libjava/classpath/javax/swing/BoxLayout.java | 746 |
1 files changed, 746 insertions, 0 deletions
diff --git a/libjava/classpath/javax/swing/BoxLayout.java b/libjava/classpath/javax/swing/BoxLayout.java new file mode 100644 index 00000000000..5dfe1d6b735 --- /dev/null +++ b/libjava/classpath/javax/swing/BoxLayout.java @@ -0,0 +1,746 @@ +/* BoxLayout.java -- A layout for swing components. + Copyright (C) 2002, 2003, 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath 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 for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + +package javax.swing; + +import java.awt.AWTError; +import java.awt.Component; +import java.awt.ComponentOrientation; +import java.awt.Container; +import java.awt.Dimension; +import java.awt.Insets; +import java.awt.LayoutManager2; +import java.io.Serializable; +import java.util.Collection; +import java.util.Iterator; +import java.util.List; +import java.util.Vector; + +import gnu.java.awt.AWTUtilities; + +/** + * A layout for swing components. + * + * @author Ronald Veldema (rveldema@cs.vu.nl) + * @author Roman Kennke (roman@kennke.org) + */ +public class BoxLayout implements LayoutManager2, Serializable +{ + + /** + * This is an abstraction that allows the BoxLayout algorithm to + * be applied to both direction (X and Y) without duplicating the + * algorithm. It defines several methods that access properties of + * a component for a specific direction. + */ + static interface Direction + { + /** + * Returns the correct part of <code>d</code> for this direction. This will + * be <code>d.width</code> for horizontal and <code>d.height</code> for + * vertical direction. + * + * @param d the size as Dimension object + * + * @return the correct part of <code>d</code> for this direction + */ + int size(Dimension d); + + /** + * Returns the lower bounds of the {@link Insets} object according to this + * direction. This will be <code>insets.top</code> for vertical direction + * and <code>insets.left</code> for horizontal direction. + * + * @param the {@link Insets} object from which to return the lower bounds + * + * @return the lower bounds of the {@link Insets} object according to this + * direction + */ + int lower(Insets insets); + + /** + * Returns the alignment property according to this direction. + * + * @param comp the Component for which to return the alignment property + * + * @return the alignment property according to this direction + */ + float alignment(Component comp); + + /** + * Sets the location for Component <code>c</code>. <code>coord1</code> + * specifies the coordinate of the location in this direction, + * <code>coord2</code> the coordinate of the location in the opposite + * direction. + * + * @param c the Component for which to set the location + * @param coord1 the coordinate in this direction + * @param coord2 the coordinate in the opposite direction + */ + void setLocation(Component c, int coord1, int coord2); + + /** + * Sets the size for Component <code>c</code>. <code>coord1</code> + * specifies the size in this direction, + * <code>coord2</code> the size in the opposite + * direction. + * + * @param c the Component for which to set the size + * @param size1 the size in this direction + * @param size2 the size in the opposite direction + */ + void setSize(Component c, int size1, int size2); + } + + /** + * The horizontal direction. + */ + static class Horizontal implements Direction + { + /** + * Returns the correct part of <code>d</code> for this direction. This will + * be <code>d.width</code> for horizontal and <code>d.height</code> for + * vertical direction. + * + * @param d the size as Dimension object + * + * @return the correct part of <code>d</code> for this direction + */ + public int size(Dimension d) + { + return d.width; + } + + /** + * Returns the lower bounds of the {@link Insets} object according to this + * direction. This will be <code>insets.top</code> for vertical direction + * and <code>insets.left</code> for horizontal direction. + * + * @param the {@link Insets} object from which to return the lower bounds + * + * @return the lower bounds of the {@link Insets} object according to this + * direction + */ + public int lower(Insets insets) + { + return insets.left; + } + + /** + * Returns the alignment property according to this direction. + * + * @param comp the Component for which to return the alignment property + * + * @return the alignment property according to this direction + */ + public float alignment(Component comp) + { + return comp.getAlignmentX(); + } + + /** + * Sets the location for Component <code>c</code>. <code>coord1</code> + * specifies the coordinate of the location in this direction, + * <code>coord2</code> the coordinate of the location in the opposite + * direction. + * + * @param c the Component for which to set the location + * @param coord1 the coordinate in this direction + * @param coord2 the coordinate in the opposite direction + */ + public void setLocation(Component c, int coord1, int coord2) + { + c.setLocation(coord1, coord2); + } + + /** + * Sets the size for Component <code>c</code>. <code>coord1</code> + * specifies the size in this direction, + * <code>coord2</code> the size in the opposite + * direction. + * + * @param c the Component for which to set the size + * @param size1 the size in this direction + * @param size2 the size in the opposite direction + */ + public void setSize(Component c, int size1, int size2) + { + c.setSize(size1, size2); + } + } + /** + * The vertical direction. + */ + static class Vertical implements Direction + { + /** + * Returns the correct part of <code>d</code> for this direction. This will + * be <code>d.width</code> for horizontal and <code>d.height</code> for + * vertical direction. + * + * @param d the size as Dimension object + * + * @return the correct part of <code>d</code> for this direction + */ + public int size(Dimension d) + { + return d.height; + } + + /** + * Returns the lower bounds of the {@link Insets} object according to this + * direction. This will be <code>insets.top</code> for vertical direction + * and <code>insets.left</code> for horizontal direction. + * + * @param the {@link Insets} object from which to return the lower bounds + * + * @return the lower bounds of the {@link Insets} object according to this + * direction + */ + public int lower(Insets insets) + { + return insets.top; + } + + /** + * Returns the alignment property according to this direction. + * + * @param comp the Component for which to return the alignment property + * + * @return the alignment property according to this direction + */ + public float alignment(Component comp) + { + return comp.getAlignmentY(); + } + + /** + * Sets the location for Component <code>c</code>. <code>coord1</code> + * specifies the coordinate of the location in this direction, + * <code>coord2</code> the coordinate of the location in the opposite + * direction. + * + * @param c the Component for which to set the location + * @param coord1 the coordinate in this direction + * @param coord2 the coordinate in the opposite direction + */ + public void setLocation(Component c, int coord1, int coord2) + { + c.setLocation(coord2, coord1); + } + + /** + * Sets the size for Component <code>c</code>. <code>coord1</code> + * specifies the size in this direction, + * <code>coord2</code> the size in the opposite + * direction. + * + * @param c the Component for which to set the size + * @param size1 the size in this direction + * @param size2 the size in the opposite direction + */ + public void setSize(Component c, int size1, int size2) + { + c.setSize(size2, size1); + } + } + + /** + * A helper class that temporarily stores the size specs of a component. + */ + static class SizeReq + { + int size; + int min; + int pref; + int max; + float align; + Component comp; + SizeReq(Component comp, Direction dir) + { + this.min = dir.size(comp.getMinimumSize()); + this.pref = dir.size(comp.getPreferredSize()); + this.max = dir.size(comp.getMaximumSize()); + this.size = dir.size(comp.getSize()); + this.align = dir.alignment(comp); + this.comp = comp; + } + } + + /** + * Specifies that components are laid out left to right. + */ + public static final int X_AXIS = 0; + + /** + * Specifies that components are laid out top to bottom. + */ + public static final int Y_AXIS = 1; + + /** + * Specifies that components are laid out in the direction of a line of text. + */ + public static final int LINE_AXIS = 2; + + /** + * Sepcifies that components are laid out in the direction of the line flow. + */ + public static final int PAGE_AXIS = 3; + + /* + * Needed for serialization. + */ + private static final long serialVersionUID = -2474455742719112368L; + + /* + * The container given to the constructor. + */ + private Container container; + + /* + * Current type of component layouting. Defaults to X_AXIS. + */ + private int way = X_AXIS; + + /** Constant for the horizontal direction. */ + private static final Direction HORIZONTAL = new Horizontal(); + + /** Constant for the vertical direction. */ + private static final Direction VERTICAL = new Vertical(); + + /** + * Constructs a <code>BoxLayout</code> object. + * + * @param container The container that needs to be laid out. + * @param way The orientation of the components. + * + * @exception AWTError If way has an invalid value. + */ + public BoxLayout(Container container, int way) + { + int width = 0; + int height = 0; + this.container = container; + this.way = way; + } + + /** + * Adds a component to the layout. Not used in BoxLayout. + * + * @param name The name of the component to add. + * @param component the component to add to the layout. + */ + public void addLayoutComponent(String name, Component component) + { + } + + /** + * Removes a component from the layout. Not used in BoxLayout. + * + * @param component The component to remove from the layout. + */ + public void removeLayoutComponent(Component component) + { + } + + private boolean isHorizontalIn(Container parent) + { + ComponentOrientation orientation = parent.getComponentOrientation(); + return this.way == X_AXIS + || (this.way == LINE_AXIS + && orientation.isHorizontal()) + || (this.way == PAGE_AXIS + && (!orientation.isHorizontal())); + } + + + + /** + * Returns the preferred size of the layout. + * + * @param parent The container that needs to be laid out. + * + * @return The dimension of the layout. + */ + public Dimension preferredLayoutSize(Container parent) + { + if (parent != container) + throw new AWTError("invalid parent"); + + Insets insets = parent.getInsets(); + int x = 0; + int y = 0; + + List children = AWTUtilities.getVisibleChildren(parent); + + if (isHorizontalIn(parent)) + { + x = insets.left + insets.right; + // sum up preferred widths of components, find maximum of preferred + // heights + for (Iterator i = children.iterator(); i.hasNext();) + { + Component comp = (Component) i.next(); + Dimension sz = comp.getPreferredSize(); + x += sz.width; + y = Math.max(y, sz.height); + } + y += insets.bottom + insets.top; + } + else + { + y = insets.top + insets.bottom; + // sum up preferred heights of components, find maximum of + // preferred widths + for (Iterator i = children.iterator(); i.hasNext();) + { + Component comp = (Component) i.next(); + Dimension sz = comp.getPreferredSize(); + y += sz.height; + x = Math.max(x, sz.width); + } + x += insets.left + insets.right; + } + + return new Dimension(x, y); + } + + /** + * Returns the minimum size of the layout. + * + * @param parent The container that needs to be laid out. + * + * @return The dimension of the layout. + */ + public Dimension minimumLayoutSize(Container parent) + { + if (parent != container) + throw new AWTError("invalid parent"); + + Insets insets = parent.getInsets(); + int x = insets.left + insets.right; + int y = insets.bottom + insets.top; + + List children = AWTUtilities.getVisibleChildren(parent); + + if (isHorizontalIn(parent)) + { + // sum up preferred widths of components, find maximum of preferred + // heights + for (Iterator i = children.iterator(); i.hasNext();) + { + Component comp = (Component) i.next(); + Dimension sz = comp.getMinimumSize(); + x += sz.width; + y = Math.max(y, sz.height); + } + } + else + { + // sum up preferred heights of components, find maximum of + // preferred widths + for (Iterator i = children.iterator(); i.hasNext();) + { + Component comp = (Component) i.next(); + Dimension sz = comp.getMinimumSize(); + y += sz.height; + x = Math.max(x, sz.width); + } + } + + return new Dimension(x, y); + } + + /** + * Lays out the specified container using this layout. + * + * @param parent The container that needs to be laid out. + */ + public void layoutContainer(Container parent) + { + if (isHorizontalIn(parent)) + layoutAlgorithm(parent, HORIZONTAL, VERTICAL); + else + layoutAlgorithm(parent, VERTICAL, HORIZONTAL); + } + + /** + * Adds a component to the layout. Not used in BoxLayout + * + * @param child The component to add to the layout. + * @param constraints The constraints for the component in the layout. + */ + public void addLayoutComponent(Component child, Object constraints) + { + } + + /** + * Returns the alignment along the X axis for the container. + * + * @param parent The container that needs to be laid out. + * + * @return The alignment. + */ + public float getLayoutAlignmentX(Container parent) + { + if (parent != container) + throw new AWTError("invalid parent"); + + return 0; + } + + /** + * Returns the alignment along the Y axis for the container. + * + * @param parent The container that needs to be laid out. + * + * @return The alignment. + */ + public float getLayoutAlignmentY(Container parent) + { + if (parent != container) + throw new AWTError("invalid parent"); + + return 0; + } + + /** + * Invalidates the layout. + * + * @param parent The container that needs to be laid out. + */ + public void invalidateLayout(Container parent) + { + if (parent != container) + throw new AWTError("invalid parent"); + } + + /** + * Returns the maximum size of the layout gived the components + * in the given container. + * + * @param parent The container that needs to be laid out. + * + * @return The dimension of the layout. + */ + public Dimension maximumLayoutSize(Container parent) + { + if (parent != container) + throw new AWTError("invalid parent"); + + Insets insets = parent.getInsets(); + int x = insets.left + insets.right; + int y = insets.top + insets.bottom; + + List children = AWTUtilities.getVisibleChildren(parent); + + if (isHorizontalIn(parent)) + { + + // sum up preferred widths of components, find maximum of preferred + // heights + for (Iterator i = children.iterator(); i.hasNext();) + { + Component comp = (Component) i.next(); + Dimension sz = comp.getMaximumSize(); + x += sz.width; + // Check for overflow. + if (x < 0) + x = Integer.MAX_VALUE; + y = Math.max(y, sz.height); + } + } + else + { + // sum up preferred heights of components, find maximum of + // preferred widths + for (Iterator i = children.iterator(); i.hasNext();) + { + Component comp = (Component) i.next(); + Dimension sz = comp.getMaximumSize(); + y += sz.height; + // Check for overflow + if (y < 0) + y = Integer.MAX_VALUE; + x = Math.max(x, sz.width); + } + } + return new Dimension(x, y); + } + + /** + * Lays out the Container <code>c</code> in the layout direction + * <code>layoutDir</code>. The direction that is crossing the layout + * direction is specified in <code>crossDir</code>. + * + * @param parent + * @param layoutDir + * @param crossDir + */ + void layoutAlgorithm(Container parent, Direction layoutDir, Direction crossDir) + { + if (parent != container) + throw new AWTError("invalid parent"); + + Dimension parentSize = parent.getSize(); + Insets insets = parent.getInsets(); + Dimension innerSize = new Dimension(parentSize.width - insets.left + - insets.right, parentSize.height + - insets.bottom - insets.top); + + // Set all components to their preferredSizes and sum up the allocated + // space. Create SizeReqs for each component and store them in + // sizeReqs. Find the maximum size in the crossing direction. + List children = AWTUtilities.getVisibleChildren(parent); + Vector sizeReqs = new Vector(); + int allocated = 0; + for (Iterator i = children.iterator(); i.hasNext();) + { + Component c = (Component) i.next(); + SizeReq sizeReq = new SizeReq(c, layoutDir); + int preferred = layoutDir.size(c.getPreferredSize()); + sizeReq.size = preferred; + allocated += preferred; + sizeReqs.add(sizeReq); + } + + // Distribute remaining space (may be positive or negative) over components + int remainder = layoutDir.size(innerSize) - allocated; + distributeSpace(sizeReqs, remainder, layoutDir); + + // Resize and relocate components. If the component can be sized to + // take the full space in the crossing direction, then do so, otherwise + // align according to its alingnmentX or alignmentY property. + int loc = 0; + int offset1 = layoutDir.lower(insets); + int offset2 = crossDir.lower(insets); + for (Iterator i = sizeReqs.iterator(); i.hasNext();) + { + SizeReq sizeReq = (SizeReq) i.next(); + Component c = sizeReq.comp; + int availCrossSize = crossDir.size(innerSize); + int maxCross = crossDir.size(c.getMaximumSize()); + int crossSize = Math.min(availCrossSize, maxCross); + int crossRemainder = availCrossSize - crossSize; + int crossLoc = (int) (crossDir.alignment(c) * crossRemainder); + layoutDir.setSize(c, sizeReq.size, crossSize); + layoutDir.setLocation(c, offset1 + loc, offset2 + crossLoc); + loc += sizeReq.size; + } + } + + /** + * Distributes some space over a set of components. This implementation + * tries to set the components as close as possible to their + * <code>preferredSize</code>s, and respects the components + * <code>minimumSize</code> and <code>maximumSize</code>. + * + * The algorithm is implemented as follows: + * + * <ul> + * <li>The <code>remainder</code> is divided by the number of components + * in <code>freeComponents</code>.</li> + * <li>The result is added to (or substracted from) the size of each + * component.</li> + * <li>If the <code>minimumSize</code> or <code>maximumSize</code> of a + * component is exceeded, then this component is set to its + * <code>minimumSize</code> or <code>maximumSize</code>, it is removed from + * <code>freeComponents</code> and the difference is added to a new + * remainder.</li> + * <li>Finally, if there is a new remainer != 0 and the + * <code>freeComponents.size() != 0</code>, then this method is called + * recursivly to distribute the newly allocated remaining space.</li> + * </ul> + * + * @param freeComponents a SizeReq collection for components that have space + * left so that they can be moved freely + * @param remainder the space that should be distributed between the + * components + * @param dir the direction in which we operate + */ + void distributeSpace(Collection freeComponents, int remainder, Direction dir) + { + // Sum up total available space in components. If the remainder is negative + // then we sum up the difference between minSize and size. If remainder + // is positive we sum up the difference between maxSize and size. + double totalAvailable = 0; + for (Iterator i = freeComponents.iterator(); i.hasNext();) + { + SizeReq sizeReq = (SizeReq) i.next(); + if (remainder >= 0) + totalAvailable += sizeReq.max - sizeReq.size; + else + totalAvailable += sizeReq.min - sizeReq.size; + } + if (totalAvailable == 0) + if (remainder >= 0) + totalAvailable = 1; + else + totalAvailable = -1; + + int newRemainder = 0; + Vector stillFree = new Vector(); + for (Iterator i = freeComponents.iterator(); i.hasNext();) + { + // Add/substract share to component. + SizeReq sizeReq = (SizeReq) i.next(); + double available = 0; + if (remainder >= 0) + available = sizeReq.max - sizeReq.size; + else + available = sizeReq.min - sizeReq.size; + int share = (int) ((available / totalAvailable) * remainder); + sizeReq.size += share; + // check for min/maximumSize + if (sizeReq.size < sizeReq.min) + { + newRemainder += sizeReq.size - sizeReq.min; + sizeReq.size = sizeReq.min; + } + else if (sizeReq.size > sizeReq.max) + { + newRemainder += sizeReq.size - sizeReq.max; + sizeReq.size = sizeReq.max; + } + else + stillFree.add(sizeReq); + } + // recursivly call this method if necessary + if (newRemainder != 0 && stillFree.size() > 0) + distributeSpace(stillFree, newRemainder, dir); + } +} |