- /*
- * @(#)CardLayout.java 1.37 03/01/23
- *
- * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
- package java.awt;
-
- import java.util.Hashtable;
- import java.util.Vector;
- import java.util.Enumeration;
-
- import java.io.Serializable;
- import java.io.ObjectInputStream;
- import java.io.ObjectOutputStream;
- import java.io.ObjectStreamField;
- import java.io.IOException;
-
- /**
- * A <code>CardLayout</code> object is a layout manager for a
- * container. It treats each component in the container as a card.
- * Only one card is visible at a time, and the container acts as
- * a stack of cards. The first component added to a
- * <code>CardLayout</code> object is the visible component when the
- * container is first displayed.
- * <p>
- * The ordering of cards is determined by the container's own internal
- * ordering of its component objects. <code>CardLayout</code>
- * defines a set of methods that allow an application to flip
- * through these cards sequentially, or to show a specified card.
- * The {@link CardLayout#addLayoutComponent}
- * method can be used to associate a string identifier with a given card
- * for fast random access.
- *
- * @version 1.37 01/23/03
- * @author Arthur van Hoff
- * @see java.awt.Container
- * @since JDK1.0
- */
-
- public class CardLayout implements LayoutManager2,
- Serializable {
-
- private static final long serialVersionUID = -4328196481005934313L;
-
- /*
- * This creates a Vector to store associated
- * pairs of components and their names.
- * @see java.util.Vector
- */
- Vector vector = new Vector();
-
- /*
- * A pair of Component and String that represents its name.
- */
- class Card implements Serializable {
- static final long serialVersionUID = 6640330810709497518L;
- public String name;
- public Component comp;
- public Card(String cardName, Component cardComponent) {
- name = cardName;
- comp = cardComponent;
- }
- }
-
- /*
- * Index of Component currently displayed by CardLayout.
- */
- int currentCard = 0;
-
-
- /*
- * A cards horizontal Layout gap (inset). It specifies
- * the space between the left and right edges of a
- * container and the current component.
- * This should be a non negative Integer.
- * @see getHgap()
- * @see setHgap()
- */
- int hgap;
-
- /*
- * A cards vertical Layout gap (inset). It specifies
- * the space between the top and bottom edges of a
- * container and the current component.
- * This should be a non negative Integer.
- * @see getVgap()
- * @see setVgap()
- */
- int vgap;
-
- /**
- * @serialField tab Hashtable
- * deprectated, for forward compatibility only
- * @serialField hgap int
- * @serialField vgap int
- * @serialField vector Vector
- * @serialField currentCard int
- */
- private static final ObjectStreamField[] serialPersistentFields = {
- new ObjectStreamField("tab", Hashtable.class),
- new ObjectStreamField("hgap", Integer.TYPE),
- new ObjectStreamField("vgap", Integer.TYPE),
- new ObjectStreamField("vector", Vector.class),
- new ObjectStreamField("currentCard", Integer.TYPE)
- };
-
- /**
- * Creates a new card layout with gaps of size zero.
- */
- public CardLayout() {
- this(0, 0);
- }
-
- /**
- * Creates a new card layout with the specified horizontal and
- * vertical gaps. The horizontal gaps are placed at the left and
- * right edges. The vertical gaps are placed at the top and bottom
- * edges.
- * @param hgap the horizontal gap.
- * @param vgap the vertical gap.
- */
- public CardLayout(int hgap, int vgap) {
- this.hgap = hgap;
- this.vgap = vgap;
- }
-
- /**
- * Gets the horizontal gap between components.
- * @return the horizontal gap between components.
- * @see java.awt.CardLayout#setHgap(int)
- * @see java.awt.CardLayout#getVgap()
- * @since JDK1.1
- */
- public int getHgap() {
- return hgap;
- }
-
- /**
- * Sets the horizontal gap between components.
- * @param hgap the horizontal gap between components.
- * @see java.awt.CardLayout#getHgap()
- * @see java.awt.CardLayout#setVgap(int)
- * @since JDK1.1
- */
- public void setHgap(int hgap) {
- this.hgap = hgap;
- }
-
- /**
- * Gets the vertical gap between components.
- * @return the vertical gap between components.
- * @see java.awt.CardLayout#setVgap(int)
- * @see java.awt.CardLayout#getHgap()
- */
- public int getVgap() {
- return vgap;
- }
-
- /**
- * Sets the vertical gap between components.
- * @param vgap the vertical gap between components.
- * @see java.awt.CardLayout#getVgap()
- * @see java.awt.CardLayout#setHgap(int)
- * @since JDK1.1
- */
- public void setVgap(int vgap) {
- this.vgap = vgap;
- }
-
- /**
- * Adds the specified component to this card layout's internal
- * table of names. The object specified by <code>constraints</code>
- * must be a string. The card layout stores this string as a key-value
- * pair that can be used for random access to a particular card.
- * By calling the <code>show</code> method, an application can
- * display the component with the specified name.
- * @param comp the component to be added.
- * @param constraints a tag that identifies a particular
- * card in the layout.
- * @see java.awt.CardLayout#show(java.awt.Container, java.lang.String)
- * @exception IllegalArgumentException if the constraint is not a string.
- */
- public void addLayoutComponent(Component comp, Object constraints) {
- synchronized (comp.getTreeLock()) {
- if (constraints instanceof String) {
- addLayoutComponent((String)constraints, comp);
- } else {
- throw new IllegalArgumentException("cannot add to layout: constraint must be a string");
- }
- }
- }
-
- /**
- * @deprecated replaced by
- * <code>addLayoutComponent(Component, Object)</code>.
- */
- public void addLayoutComponent(String name, Component comp) {
- synchronized (comp.getTreeLock()) {
- if (!vector.isEmpty()) {
- comp.setVisible(false);
- }
- for (int i=0; i < vector.size(); i++) {
- if (((Card)vector.get(i)).name.equals(name)) {
- ((Card)vector.get(i)).comp = comp;
- return;
- }
- }
- vector.add(new Card(name, comp));
- }
- }
-
- /**
- * Removes the specified component from the layout.
- * @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) {
- synchronized (comp.getTreeLock()) {
- for (int i = 0; i < vector.size(); i++) {
- if (((Card)vector.get(i)).comp == comp) {
- // if we remove current component we should show next one
- if (comp.isVisible() && (comp.getParent() != null)) {
- next(comp.getParent());
- }
-
- vector.remove(i);
-
- // correct currentCard if this is necessary
- if (currentCard > i) {
- currentCard--;
- }
- break;
- }
- }
- }
- }
-
- /**
- * Determines the preferred size of the container argument using
- * this card layout.
- * @param parent the name of the parent container.
- * @return the preferred dimensions to lay out the subcomponents
- * of the specified container.
- * @see java.awt.Container#getPreferredSize
- * @see java.awt.CardLayout#minimumLayoutSize
- */
- public Dimension preferredLayoutSize(Container parent) {
- synchronized (parent.getTreeLock()) {
- Insets insets = parent.getInsets();
- int ncomponents = parent.getComponentCount();
- int w = 0;
- int h = 0;
-
- for (int i = 0 ; i < ncomponents ; i++) {
- Component comp = parent.getComponent(i);
- Dimension d = comp.getPreferredSize();
- if (d.width > w) {
- w = d.width;
- }
- if (d.height > h) {
- h = d.height;
- }
- }
- return new Dimension(insets.left + insets.right + w + hgap*2,
- insets.top + insets.bottom + h + vgap*2);
- }
- }
-
- /**
- * Calculates the minimum size for the specified panel.
- * @param parent the name of the parent container
- * in which to do the layout.
- * @return the minimum dimensions required to lay out the
- * subcomponents of the specified container.
- * @see java.awt.Container#doLayout
- * @see java.awt.CardLayout#preferredLayoutSize
- */
- public Dimension minimumLayoutSize(Container parent) {
- synchronized (parent.getTreeLock()) {
- Insets insets = parent.getInsets();
- int ncomponents = parent.getComponentCount();
- int w = 0;
- int h = 0;
-
- for (int i = 0 ; i < ncomponents ; i++) {
- Component comp = parent.getComponent(i);
- Dimension d = comp.getMinimumSize();
- if (d.width > w) {
- w = d.width;
- }
- if (d.height > h) {
- h = d.height;
- }
- }
- return new Dimension(insets.left + insets.right + w + hgap*2,
- insets.top + insets.bottom + h + vgap*2);
- }
- }
-
- /**
- * Returns the maximum dimensions for this layout given the components
- * in the specified target container.
- * @param target the component which needs to be laid out
- * @see Container
- * @see #minimumLayoutSize
- * @see #preferredLayoutSize
- */
- 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.
- */
- 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.
- */
- 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 card layout.
- * <p>
- * Each component in the <code>parent</code> container is reshaped
- * to be the size of the container, minus space for surrounding
- * insets, horizontal gaps, and vertical gaps.
- *
- * @param parent the name of the parent container
- * in which to do the layout.
- * @see java.awt.Container#doLayout
- */
- public void layoutContainer(Container parent) {
- synchronized (parent.getTreeLock()) {
- Insets insets = parent.getInsets();
- int ncomponents = parent.getComponentCount();
- Component comp = null;
- boolean currentFound = false;
-
- for (int i = 0 ; i < ncomponents ; i++) {
- comp = parent.getComponent(i);
- comp.setBounds(hgap + insets.left, vgap + insets.top,
- parent.width - (hgap*2 + insets.left + insets.right),
- parent.height - (vgap*2 + insets.top + insets.bottom));
- if (comp.isVisible()) {
- currentFound = true;
- }
- }
-
- if (!currentFound && ncomponents > 0) {
- parent.getComponent(0).setVisible(true);
- }
- }
- }
-
- /**
- * Make sure that the Container really has a CardLayout installed.
- * Otherwise havoc can ensue!
- */
- void checkLayout(Container parent) {
- if (parent.getLayout() != this) {
- throw new IllegalArgumentException("wrong parent for CardLayout");
- }
- }
-
- /**
- * Flips to the first card of the container.
- * @param parent the name of the parent container
- * in which to do the layout.
- * @see java.awt.CardLayout#last
- */
- public void first(Container parent) {
- synchronized (parent.getTreeLock()) {
- checkLayout(parent);
- int ncomponents = parent.getComponentCount();
- for (int i = 0 ; i < ncomponents ; i++) {
- Component comp = parent.getComponent(i);
- if (comp.isVisible()) {
- comp.setVisible(false);
- break;
- }
- }
- if (ncomponents > 0) {
- currentCard = 0;
- parent.getComponent(0).setVisible(true);
- parent.validate();
- }
- }
- }
-
- /**
- * Flips to the next card of the specified container. If the
- * currently visible card is the last one, this method flips to the
- * first card in the layout.
- * @param parent the name of the parent container
- * in which to do the layout.
- * @see java.awt.CardLayout#previous
- */
- public void next(Container parent) {
- synchronized (parent.getTreeLock()) {
- checkLayout(parent);
- int ncomponents = parent.getComponentCount();
- for (int i = 0 ; i < ncomponents ; i++) {
- Component comp = parent.getComponent(i);
- if (comp.isVisible()) {
- comp.setVisible(false);
- currentCard = (i + 1) % ncomponents;
- comp = parent.getComponent(currentCard);
- comp.setVisible(true);
- parent.validate();
- return;
- }
- }
- showDefaultComponent(parent);
- }
- }
-
- /**
- * Flips to the previous card of the specified container. If the
- * currently visible card is the first one, this method flips to the
- * last card in the layout.
- * @param parent the name of the parent container
- * in which to do the layout.
- * @see java.awt.CardLayout#next
- */
- public void previous(Container parent) {
- synchronized (parent.getTreeLock()) {
- checkLayout(parent);
- int ncomponents = parent.getComponentCount();
- for (int i = 0 ; i < ncomponents ; i++) {
- Component comp = parent.getComponent(i);
- if (comp.isVisible()) {
- comp.setVisible(false);
- currentCard = ((i > 0) ? i-1 : ncomponents-1);
- comp = parent.getComponent(currentCard);
- comp.setVisible(true);
- parent.validate();
- return;
- }
- }
- showDefaultComponent(parent);
- }
- }
-
- void showDefaultComponent(Container parent) {
- if (parent.getComponentCount() > 0) {
- currentCard = 0;
- parent.getComponent(0).setVisible(true);
- parent.validate();
- }
- }
-
- /**
- * Flips to the last card of the container.
- * @param parent the name of the parent container
- * in which to do the layout.
- * @see java.awt.CardLayout#first
- */
- public void last(Container parent) {
- synchronized (parent.getTreeLock()) {
- checkLayout(parent);
- int ncomponents = parent.getComponentCount();
- for (int i = 0 ; i < ncomponents ; i++) {
- Component comp = parent.getComponent(i);
- if (comp.isVisible()) {
- comp.setVisible(false);
- break;
- }
- }
- if (ncomponents > 0) {
- currentCard = ncomponents - 1;
- parent.getComponent(currentCard).setVisible(true);
- parent.validate();
- }
- }
- }
-
- /**
- * Flips to the component that was added to this layout with the
- * specified <code>name</code>, using <code>addLayoutComponent</code>.
- * If no such component exists, then nothing happens.
- * @param parent the name of the parent container
- * in which to do the layout.
- * @param name the component name.
- * @see java.awt.CardLayout#addLayoutComponent(java.awt.Component, java.lang.Object)
- */
- public void show(Container parent, String name) {
- synchronized (parent.getTreeLock()) {
- checkLayout(parent);
- Component next = null;
- int ncomponents = vector.size();
- for (int i = 0; i < ncomponents; i++) {
- Card card = (Card)vector.get(i);
- if (card.name.equals(name)) {
- next = card.comp;
- currentCard = i;
- break;
- }
- }
- if ((next != null) && !next.isVisible()) {
- ncomponents = parent.getComponentCount();
- for (int i = 0; i < ncomponents; i++) {
- Component comp = parent.getComponent(i);
- if (comp.isVisible()) {
- comp.setVisible(false);
- break;
- }
- }
- next.setVisible(true);
- parent.validate();
- }
- }
- }
-
- /**
- * Returns a string representation of the state of this card layout.
- * @return a string representation of this card layout.
- */
- public String toString() {
- return getClass().getName() + "[hgap=" + hgap + ",vgap=" + vgap + "]";
- }
-
- /**
- * Reads serializable fields from stream.
- */
- private void readObject(ObjectInputStream s)
- throws ClassNotFoundException, IOException
- {
- ObjectInputStream.GetField f = s.readFields();
-
- hgap = f.get("hgap", 0);
- vgap = f.get("vgap", 0);
-
- if (f.defaulted("vector")) {
- // pre-1.4 stream
- Hashtable tab = (Hashtable)f.get("tab", null);
- vector = new Vector();
- if (tab != null && !tab.isEmpty()) {
- for (Enumeration e = tab.keys() ; e.hasMoreElements() ; ) {
- String key = (String)e.nextElement();
- Component comp = (Component)tab.get(key);
- vector.add(new Card(key, comp));
- if (comp.isVisible()) {
- currentCard = vector.size() - 1;
- }
- }
- }
- } else {
- vector = (Vector)f.get("vector", null);
- currentCard = f.get("currentCard", 0);
- }
- }
-
- /**
- * Writes serializable fields to stream.
- */
- private void writeObject(ObjectOutputStream s)
- throws IOException
- {
- Hashtable tab = new Hashtable();
- int ncomponents = vector.size();
- for (int i = 0; i < ncomponents; i++) {
- Card card = (Card)vector.get(i);
- tab.put(card.name, card.comp);
- }
-
- ObjectOutputStream.PutField f = s.putFields();
- f.put("hgap", hgap);
- f.put("vgap", vgap);
- f.put("vector", vector);
- f.put("currentCard", currentCard);
- f.put("tab", tab);
- s.writeFields();
- }
- }