navpanel.java

该系统是一个基于p2p的即时聊天系统

/*
 * @(#) NAVPanel.java
 * Copyright 2004 HWStudio. All rights reserved.
 */
package hws.item.smart.panel.navbar;
//导入核心Java类库
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.FontMetrics;
import java.awt.Image;
import java.awt.Point;
import java.awt.Button;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.util.List;
import java.util.ArrayList;
import javax.swing.JPanel;
//导入自定义Java类库
import hws.item.smart.misc.ColorShop;
import hws.item.smart.misc.ImageShop;
/**
 * 导航面板
 *
 * @version 0.1 2005-08-07
 * @author Hwerz
 */
public class NAVPanel extends JPanel
    implements ActionListener, MouseListener, MouseMotionListener {
    /*------------------------------------------------------------------------*
     *                                属性定义                                *
     *------------------------------------------------------------------------*/
    /**
     * 按钮标签的字体
     */
    public static final Font BUTTON_FONT = new Font("宋体", Font.PLAIN, 12);
    /**
     * 导航面板容纳按钮的总数
     */
    private static final int BUTTON_COUNT = 20;
    /**
     * 导航面板上的父按钮数组
     */
    private Button parentButtons[];
    /**
     * 已经添加到面板上的父按钮个数
     */
    private int numberOfParentButton;
    /**
     * 被选中父按钮的索引
     */
    private int selectedParentButtonIndex;
    /**
     * 父按钮的高度
     */
    private int heightOfParentButton;
    /**
     * 每个父按钮里面所包括的子按钮
     */
    private Image sonButtons[][];
    /**
     * 子按钮的标签
     */
    private String sonButtonLabels[][];
    /**
     * 每个组里子按钮的个数
     */
    private int numberOfSonButton[];
    /**
     * 子按钮所占面板宽度的比例
     */
    private int widthPercentOfSonButton;
    /**
     * 子按钮之间的间距
     */
    private int deltaBetweenSonButtons;
    /**
     * 第一个被显示的子按钮
     */
    private int theFirstDisplaySonButton;
    /**
     * 被按下的子按钮
     */
    private int pressedSonButton;
    /**
     * 单击则向上滚动的带箭头小按钮
     */
    private Image slideUpButton;
    /**
     * 单击则向下滚动的带箭头小按钮
     */
    private Image slideDownButton;
    /**
     * 是否显示slideDownButton
     */
    private boolean showSlideDownButton;
    /**
     * 子按钮的滚动次数
     */
    private int slideStep;
    /**
     * 子按钮的滚动节奏
     */
    private int slideIndex;
    /**
     * 记录鼠标的当前位置
     */
    private Point mousePoint;
    /**
     * 事件监听器集合
     */
    private List listeners;
    /*------------------------------------------------------------------------*
     *                                构造函数                                *
     *------------------------------------------------------------------------*/
    /**
     * Create a new instance of this class
     */
    public NAVPanel() {
        super();
        parentButtons = new Button[BUTTON_COUNT];
        numberOfParentButton = 0;
        selectedParentButtonIndex = -1;
        heightOfParentButton = 25;
        
        sonButtons = new Image[BUTTON_COUNT][BUTTON_COUNT];
        sonButtonLabels = new String[BUTTON_COUNT][BUTTON_COUNT];
        numberOfSonButton = new int[BUTTON_COUNT];
        
        widthPercentOfSonButton = 40;
        deltaBetweenSonButtons = 20;
        theFirstDisplaySonButton = -1;
        pressedSonButton = -1;
        
        slideUpButton = ImageShop.UP_IMAGEICON.getImage();
        slideDownButton = ImageShop.DOWN_IMAGEICON.getImage();
        slideStep = 3;
        showSlideDownButton = false;
        slideIndex = 0;
        
        mousePoint = null;
        
        listeners = new ArrayList();
        
        setLayout(null);
        setBackground(ColorShop.NAVPANEL_BG_COLOR);
        addMouseMotionListener(this);
        addMouseListener(this);
    }
    /*------------------------------------------------------------------------*
     *                                公共方法                                *
     *------------------------------------------------------------------------*/
    /**
     * 添加SonButtonClickedListener事件监听器
     *
     * @param listener 待添加的SonButtonClickedListener
     */
    public synchronized void addSonButtonClickedListener(
        SonButtonClickedListener listener) {
        listeners.add(listener);
    }
    /**
     * 删除SonButtonClickedListener事件监听器
     *
     * @param listener 待删除的SonButtonClickedListener
     */
    public synchronized void removeSonButtonClickedListener(
        SonButtonClickedListener listener) {
        listeners.remove(listener);
    }
    /**
     * 返回父按钮的个数
     *
     * @return 父按钮的个数
     */
    public int getNumberOfParentButton() {
        return numberOfParentButton;
    }
    /**
     * 返回指定索引的父按钮对象
     *
     * @param index 父按钮的索引
     * @return 指定索引的父按钮对象
     */
    public Button getParentButton(int index) {
        Button parentButton = null;
        if (index >= 0 && index < numberOfParentButton) {
            parentButton = parentButtons[index];
        }
        return parentButton;
    }
    /**
     * 添加父按钮
     *
     * @param text 待添加父按钮的文本
     * @return 如果添加成功则返回true，否则返回false
     */
    public boolean addParentButton(String text) {
        boolean success = false;
        int i = numberOfParentButton;
        if (i < BUTTON_COUNT) {
            Button button = new Button(text);
            parentButtons[i] = button;
            numberOfSonButton[i] = 0;
            numberOfParentButton++;
            add(button);
            button.addActionListener(this);
            setSelectedParentButton(i);
            success = true;
        } 
        return success;
    }
    /**
     * 向指定的父按钮所在的组里添加子按钮
     *
     * @param index 指定父按钮的索引
     * @param image 待添加子按钮的图标
     * @param text 待添加子按钮的文本
     */
    public void addSonToParent(int index, Image image, String text) {
        if (index < numberOfParentButton 
            && numberOfSonButton[index] < BUTTON_COUNT) {
            sonButtons[index][numberOfSonButton[index]] = image;
            sonButtonLabels[index][numberOfSonButton[index]] = text;
            numberOfSonButton[index]++;
            repaint();
        }
    }
    /**
     * 选中指定索引的父按钮
     *
     * @param index 父按钮的索引
     */
    public void setSelectedParentButton(int index) {
        if (index >= 0 && index < numberOfParentButton) {
            if (selectedParentButtonIndex != index) {
                selectedParentButtonIndex = index;
                theFirstDisplaySonButton = 0;
                repaint();
            }
        }
    }
    /*------------------------------------------------------------------------*
     *                                私有方法                                *
     *------------------------------------------------------------------------*/
    /**
     * 返回子按钮的宽度(注意：所有子按钮的宽度都一致)
     *
     * @return 子按钮的宽度
     */
    private int getSonButtonWidth() {
        return (widthPercentOfSonButton * getWidth()) / 100;
    }
    /**
     * 返回指定子按钮的边界(注意：这个子按钮是隶属于当前选定的父按钮)
     *
     * @param index 子按钮的索引号
     * @return 子按钮的边界
     */
    private Rectangle getSonButtonRectangle(int index) {
        int x = (getWidth() - getSonButtonWidth()) / 2;
        int y = (selectedParentButtonIndex + 1) * heightOfParentButton
            + (index - theFirstDisplaySonButton) * (getSonButtonWidth()
            + deltaBetweenSonButtons) + deltaBetweenSonButtons / 2;
        Rectangle rectangle = new Rectangle(x, y, getSonButtonWidth(),
            getSonButtonWidth());
        return rectangle;
    }
    /**
     * 返回slideDownButton的边界
     *
     * @return slideDownButton的边界
     */
    private Rectangle getSlideDownButtonRect() {
        int y = getHeight() - (numberOfParentButton
            - selectedParentButtonIndex) * heightOfParentButton;
        Rectangle rectangle = new Rectangle(getWidth() - 20, y, 16, 16);
        return rectangle;
    }
    /**
     * 返回slideUpButton的边界
     *
     * @return slideUpButton的边界
     */
    private Rectangle getSlideUpButtonRect() {
        int y = (selectedParentButtonIndex + 1) * heightOfParentButton + 16;
        Rectangle rectangle = new Rectangle(getWidth() - 20, y, 16, 16);
        return rectangle;
    }
    /**
     * 返回指定位置处按钮的索引如果是父按钮，则返回值为索引的相反数减去2；如果是子按
     * 钮，则返回索引值
     *
     * @param point 指定的位置
     * @return 指定位置处按钮的索引
     */
    private int getButtonIndex(Point point) {
        int index = -1;
        if (point != null) {
            if (numberOfParentButton != 0) {
                for (int i = 0; i < numberOfParentButton; i++) {
                    Rectangle rectangle = getParentButton(i).getBounds();
                    //鼠标在某一父按钮的上面
                    if (rectangle.contains(point)) {
                        index = -i - 2;
                        break;
                    }
                }
                if (index == -1) {
                    for (int i = theFirstDisplaySonButton;
                        i < theFirstDisplaySonButton
                        + numberOfSonButton[selectedParentButtonIndex]; i++) {
                        Rectangle rectangle = getSonButtonRectangle(i);
                        //鼠标在某一子按钮的上面
                        if (rectangle.contains(point)) {
                            index = i;
                            break;
                        }
                    }
                }
            }