messagepanel.java

用JAVA编写的指针式圆形电子钟

import java.awt.FontMetrics;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.JPanel;

public class MessagePanel extends JPanel
{
	private String message ="welcome to java";
	private int xCoordinate = 20;
	private int yCoordinate = 20;
	private boolean centered;
	private int interval = 10;
	
	public MessagePanel(){
	}
		
	public MessagePanel(String message)
	{
		this.message= message;
	}
	
	public String getMessage(String message)
	{
		return message;
	}
	
	public void setMassage(String message)
	{
		this.message=message;
		repaint();
	}
	
	public int getXCoordinate(){
		return xCoordinate;
	}
	
	public void setXCoordinate(int x){
	this.xCoordinate = x;
	repaint();	
	}
	
	public int getYCoordinate(){
		return yCoordinate;
	}
	
	public void detYCoordinate(int y){
		this.yCoordinate=y;
		repaint();
	}
	
	public boolean isCentered()
	{
		return centered;
	}
	
	public void setCentered(boolean centered){
		this.centered=centered;
		repaint();
	}
	
	public int getInterval(){
		return interval;
	}
	
	public void setInterval(int interval){
		this.interval=interval;
		repaint();
	}
	
	protected void paintcomponent(Graphics g)
	{
		super.paintComponent(g);
		
		if (centered)
		{
			FontMetrics fm = g.getFontMetrics();
			int stringWidth = fm.stringWidth(message);
			int stringAscent = fm.getAscent();
			
			xCoordinate = getWidth()/2 - stringWidth/2;
			yCoordinate = getHeight()/2 - stringAscent/2;
		}
		g.drawString(message,xCoordinate,yCoordinate);	
	}
	
	public void moveLeft()
	{
		xCoordinate -= interval;
		repaint();
	}
	
	public void moveRight()
	{
		xCoordinate -= interval;
		repaint();
	}
	
	public void moveUp()
	{
		yCoordinate -= interval;
		repaint();
	}
	
	public void moveDown()
	{
		yCoordinate += interval;
		repaint();
	}
	
	public Dimension getPreferedSize()
	{
		return new Dimension(200,30);
	}
		
}