borderpanel.java

java高级使用教程 全书一共分六章

// BorderPanel - a panel that adds a border around the contents
//
// Copyright (C) 1996 by Jef Poskanzer <[e-mail]>.  All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE.
//
// Visit the ACME Labs Java page for up-to-date versions of this and other
// fine Java utilities: http://www.acme.com/java/

package Acme.Widgets;

import java.awt.*;
import java.awt.image.*;

/// A panel that adds a border around the contents.
// <P>
// Sample usage:
// <IMG ALIGN=RIGHT WIDTH=340 HEIGHT=60 SRC="BorderPanel.png">
// <BLOCKQUOTE><PRE><CODE>
// BorderPanel p = new BorderPanel( BorderPanel.IN );
// </CODE></PRE></BLOCKQUOTE>
// <P>
// <A HREF="/resources/classes/Acme/Widgets/BorderPanel.java">Fetch the software.</A><BR>
// <A HREF="/resources/classes/Acme.tar.gz">Fetch the entire Acme package.</A>

public class BorderPanel extends Panel
    {

    public static final int SOLID = 0;
    public static final int RAISED = 1;
    public static final int LOWERED = 2;
    public static final int IN = 3;
    public static final int OUT = 4;

    private int type;
    private int thickness;

    private Panel innerPanel = null;

    /// Constructor.
    public BorderPanel( int type, int thickness )
	{
	this.type = type;
	this.thickness = thickness;
	build();
	}

    /// Constructor, default thickness for this type.
    public BorderPanel( int type )
	{
	this.type = type;
	switch ( type )
	    {
	    case SOLID:
	    thickness = 2;
	    break;
	    case RAISED:
	    thickness = 2;
	    break;
	    case LOWERED:
	    thickness = 2;
	    break;
	    case IN:
	    thickness = 2;
	    break;
	    case OUT:
	    thickness = 2;
	    break;
	    }
	build();
	}
    
    private void build()
	{
	// Make the inner panel.
	Panel ip = new Panel();

	// Add the inner panel using a GridBagLayout because that layout
	// manager implements inserts.
	GridBagLayout gb = new GridBagLayout();
	setLayout( gb );
	GridBagConstraints gbc = new GridBagConstraints();
	gbc.fill = GridBagConstraints.BOTH;
	gbc.weightx = gbc.weighty = 1.0;
	gbc.insets = new Insets( thickness, thickness, thickness, thickness );
	gb.setConstraints( ip, gbc );
	add( ip, -1 );

	// And set the inner panel so that the delegated methods start using it.
	innerPanel = ip;
	}


    /// Paint the border.
    public void paint( Graphics graphics )
	{
	Dimension size = size();
	// Dimension size = getSize();
	graphics.setColor( getBackground() );
	switch ( type )
	    {
	    case SOLID:
	    graphics.setColor( getForeground() );
	    for ( int i = 0; i < thickness; ++i )
		graphics.drawRect(
		    i, i, size.width - i * 2 - 1, size.height - i * 2 - 1 );
	    break;

	    case RAISED:
	    for ( int i = 0; i < thickness; ++i )
		graphics.draw3DRect(
		    i, i, size.width - i * 2 - 1, size.height - i * 2 - 1,
		    true );
	    break;

	    case LOWERED:
	    for ( int i = 0; i < thickness; ++i )
		graphics.draw3DRect(
		    i, i, size.width - i * 2 - 1, size.height - i * 2 - 1,
		    false );
	    break;

	    case IN:
	    graphics.draw3DRect( 0, 0, size.width - 1, size.height - 1, false );
	    graphics.draw3DRect(
		thickness - 1, thickness - 1,
		size.width - thickness * 2 + 1, size.height - thickness * 2 + 1,
		true );
	    break;

	    case OUT:
	    graphics.draw3DRect( 0, 0, size.width - 1, size.height - 1, true );
	    graphics.draw3DRect(
		thickness - 1, thickness - 1,
		size.width - thickness * 2 + 1, size.height - thickness * 2 + 1,
		false );
	    break;
	    }
	}


    // Delegate other Container/Panel methods to the superclass if we
    // are initializing, otherwise to the inner panel.

    public int countComponents()
	{
	if ( innerPanel == null )
	    return super.getComponentCount();
	else
	    return innerPanel.getComponentCount();
	}
    public Component getComponent( int n )
	{
	if ( innerPanel == null )
	    return super.getComponent( n );
	else
	    return innerPanel.getComponent( n );
	}
    public Insets insets( int n )
	{
	if ( innerPanel == null )
	    return super.getInsets();
	else
	    return innerPanel.getInsets();
	}
    public Component add( Component comp )
	{
	if ( innerPanel == null )
	    return super.add( comp );
	else
	    return innerPanel.add( comp );
	}
    public Component add( Component comp, int pos )
	{
	if ( innerPanel == null )
	    return super.add( comp, pos );
	else
	    return innerPanel.add( comp, pos );
	}
    public Component add( String name, Component comp )
	{
	if ( innerPanel == null )
	    return super.add( name, comp );
	else
	    return innerPanel.add( name, comp );
	}
    public void remove( Component comp )
	{
	if ( innerPanel == null )
	    super.remove( comp );
	else
	    innerPanel.remove( comp );
	}
    public void removeAll()
	{
	if ( innerPanel == null )
	    super.removeAll();
	else
	    innerPanel.removeAll();
	}
    public LayoutManager getLayout()
	{
	if ( innerPanel == null )
	    return super.getLayout();
	else
	    return innerPanel.getLayout();
	}
    public void setLayout( LayoutManager mgr )
	{
	if ( innerPanel == null )
	    super.setLayout( mgr );
	else
	    innerPanel.setLayout( mgr );
	}

    }