/*
* @(#)CardLayout.java 1.10 95/11/14 Arthur van Hoff
*
* Copyright (c) 1994-1995 Sun Microsystems, Inc. All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file "copyright.html"
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
package java.awt;
import java.util.Hashtable;
import java.util.Enumeration;
/**
* A layout manager for a container that contains several
* 'cards'. Only one card is visible at the same time,
* allowing you to flip through the cards.
*
* @version 1.10 14 Nov 1995
* @author Arthur van Hoff
*/
public class CardLayout implements LayoutManager {
Hashtable tab = new Hashtable();
int hgap;
int vgap;
/**
* Creates a new card layout.
*/
public CardLayout() {
this(0, 0);
}
/**
* Creates a card layout with the specified gaps.
* @param hgap the horizontal gap
* @param vgap the vertical gap
*/
public CardLayout(int hgap, int vgap) {
this.hgap = hgap;
this.vgap = vgap;
}
/**
* Adds the specified component with the specified name to the layout.
* @param name the name of the component
* @param comp the component to be added
*/
public void addLayoutComponent(String name, Component comp) {
if (tab.size() > 0) {
comp.hide();
}
tab.put(name, comp);
}
/**
* Removes the specified component from the layout.
* @param comp the component to be removed
*/
public void removeLayoutComponent(Component comp) {
for (Enumeration e = tab.keys() ; e.hasMoreElements() ; ) {
String key = (String)e.nextElement();
if (tab.get(key) == comp) {
tab.remove(key);
return;
}
}
}
/**
* Calculates the preferred size for the specified panel.
* @param parent the name of the parent container
* @return the dimensions of this panel.
* @see #minimumLayoutSize
*/
public Dimension preferredLayoutSize(Container parent) {
Insets insets = parent.insets();
int ncomponents = parent.countComponents();
int w = 0;
int h = 0;
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
Dimension d = comp.preferredSize();
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
* @return the dimensions of this panel.
* @see #preferredLayoutSize
*/
public Dimension minimumLayoutSize(Container parent) {
Insets insets = parent.insets();
int ncomponents = parent.countComponents();
int w = 0;
int h = 0;
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
Dimension d = comp.minimumSize();
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);
}
/**
* Performs a layout in the specified panel.
* @param parent the name of the parent container
*/
public void layoutContainer(Container parent) {
synchronized (parent) {
Insets insets = parent.insets();
int ncomponents = parent.countComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
if (comp.visible) {
comp.reshape(hgap + insets.left, vgap + insets.top,
parent.width - (hgap*2 + insets.left + insets.right),
parent.height - (vgap*2 + insets.top + insets.bottom));
}
}
}
}
/**
* 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");
}
}
/**
* Flip to the first card.
* @param parent the name of the parent container
*/
public void first(Container parent) {
synchronized (parent) {
checkLayout(parent);
int ncomponents = parent.countComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
if (comp.visible) {
comp.hide();
comp = parent.getComponent(0);
comp.show();
parent.validate();
return;
}
}
}
}
/**
* Flips to the next card of the specified container.
* @param parent the name of the container
*/
public void next(Container parent) {
synchronized (parent) {
checkLayout(parent);
int ncomponents = parent.countComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
if (comp.visible) {
comp.hide();
comp = parent.getComponent((i + 1 < ncomponents) ? i+1 : 0);
comp.show();
parent.validate();
return;
}
}
}
}
/**
* Flips to the previous card of the specified container.
* @param parent the name of the parent container
*/
public void previous(Container parent) {
synchronized (parent) {
checkLayout(parent);
int ncomponents = parent.countComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
if (comp.visible) {
comp.hide();
comp = parent.getComponent((i > 0) ? i-1 : ncomponents-1);
comp.show();
parent.validate();
return;
}
}
}
}
/**
* Flips to the last card of the specified container.
* @param parent the name of the parent container
*/
public void last(Container parent) {
synchronized (parent) {
checkLayout(parent);
int ncomponents = parent.countComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
if (comp.visible) {
comp.hide();
comp = parent.getComponent(ncomponents - 1);
comp.show();
parent.validate();
return;
}
}
}
}
/**
* Flips to the specified component name in the specified container.
* @param parent the name of the parent container
* @param name the component name
*/
public void show(Container parent, String name) {
synchronized (parent) {
checkLayout(parent);
Component next = (Component)tab.get(name);
if ((next != null) && !next.visible){
int ncomponents = parent.countComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = parent.getComponent(i);
if (comp.visible) {
comp.hide();
break;
}
}
next.show();
parent.validate();
}
}
}
/**
* Returns the String representation of this CardLayout's values.
*/
public String toString() {
return getClass().getName() + "[hgap=" + hgap + ",vgap=" + vgap + "]";
}
}