controlbar.java

mp3的播放

/**************************************************************************
 *	(C) Copyright 2008 by  Tao Liuyuan and Zhang Shuitao.                       *
 *		All Rights Reserved.               								  *
 *     																      *
 *	Project					: KYPlayer									  *
 *	File					: ControlBar.java 						      *	
 *	JDK version used        : jdk1.6.0_u4							      *
 * 	Version                 : 1.00				     					  *
 * 	Created				    : 2008.7.6 by we					  *
 *************************************************************************/
package MP3Player;

import java.awt.Color;
import java.awt.Cursor;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;

import javax.swing.JPanel;

/**
 * 控制拖动条类
 * @author  we
 */
public class ControlBar extends JPanel implements MouseListener, 
										MouseMotionListener{
	
	/**
	 * 自动生成的序列化值
	 */
	private static final long serialVersionUID = 1L;
	
	/**
	 * 拖动位置的比例
	 */
	private double processPercent = 0;
	
	/**
	 * processPercent属性的get方法
	 * @return double
	 */
	public double getProcessPercent() {
		return processPercent;
	}
	
	/**
	 * processPercent属性的set方法，并对拖拉钮进行重定位
	 * @param processPercent
	 */
	public void setProcessPercent(double processPercent) {
		if (processPercent < 0)
			processPercent = 0;
		if (processPercent > 1)
			processPercent = 1;
		
		this.processPercent = processPercent;
		resetBar();
	}

	/**
	 * 根据位置比例重设控制条
	 * @param processPercent
	 */
	private void resetBar() {
		startX = (int)((getWidth()-21)*processPercent);
		repaint();
	}

	/**
	 * 拖拉钮的位置
	 */
	private int startX = 0;

	/**
	 * 重载的重绘组件函数
	 */
	public void paintComponent(Graphics g) {
		super.paintComponent(g);
		
		g.setColor(Color.gray);
		g.drawLine(0, getHeight()/2, getWidth()-1, getHeight()/2);
		
		g.setColor(Color.black);
		g.drawRoundRect(startX, 0, 20, getHeight()-1, 2, 2);
		g.setColor(Color.lightGray);
		g.fillRoundRect(startX+1, 1, 19, getHeight()-2, 2, 2);
		}
	
	/**
	 * 构造函数,改变光标形状
	 */
	public ControlBar() {
		super();

		setCursor(new Cursor(Cursor.HAND_CURSOR));
		addMouseListener(this);
		addMouseMotionListener(this);

		repaint();
	}

	/**
	 * 根据鼠标动作重设工具条
	 * @param e
	 */
	public void reset(MouseEvent e) {
		if (e.getX() < 10)
			startX = 0;
		else if (e.getX() > getWidth()-11)
			startX = getWidth()-21;
		else
			startX = e.getX()-10;
		
		processPercent = (double)startX / (double)(getWidth()-21);
		repaint();
	}
	
	/**
	 * 对控制条进行操作完毕后执行的函数
	 */
	public void done() {
	}
	
	/**
	 * 根据鼠标动作重设提示信息
	 * @param e
	 */
	public void setTip(MouseEvent e) {
		int percentInterger = getPointerPostion(e);
		setToolTipText(Integer.toString(percentInterger) + "%");
	}

	/**
	 * 根据鼠标位置确定位置比例
	 * @param e
	 * @return int
	 */
	public int getPointerPostion(MouseEvent e) {
		int percentInterger = (e.getX()-10)*100 / (getWidth()-21);
		if(percentInterger < 0) 
			percentInterger = 0;
		else if (percentInterger > 100)
			percentInterger = 100;
		return percentInterger;
	}
	
	@Override
	public void mouseClicked(MouseEvent e) {
	}

	@Override
	public void mouseEntered(MouseEvent e) {
		
	}

	@Override
	public void mouseExited(MouseEvent e) {
	}

	/**
	 * 鼠标单击响应
	 */
	@Override
	public void mousePressed(MouseEvent e) {
		reset(e);
	}

	/**
	 * 鼠标拖放结束响应
	 */
	@Override
	public void mouseReleased(MouseEvent e) {	
		done();
	}

	/**
	 * 鼠标拖放响应
	 */
	@Override
	public void mouseDragged(MouseEvent e) {
		reset(e);
	}

	/**
	 * 鼠标移动响应
	 */
	@Override
	public void mouseMoved(MouseEvent e) {
		setTip(e);
	}
}