软件工程P37习题四程序代码

//可移动的HelloWord语句  import java.awt.Color; import java.awt.Cursor; import java.awt.Font; import java.awt.Point; import java.awt.event.MouseEvent;

import javax.swing.JLabel; import javax.swing.JWindow; import javax.swing.event.MouseInputListener;

public class GuiHelloWorld extends JWindow { private static final long serialVersionUID = 1L; JLabel titleLbl; Font GuiHelloWorldFont;

public GuiHelloWorld() { GuiHelloWorldFont = new Font("幼圆", Font.ITALIC, 28);

this.getContentPane().setBackground(new Color(0x99FF66)); this.setBounds(400, 200, 200, 60); this.setLayout(null);

titleLbl = new JLabel(" Hello World!"); titleLbl.setFont(GuiHelloWorldFont); titleLbl.setOpaque(true); titleLbl.setBackground(new Color(0x66CC00)); titleLbl.setBounds(0, 0, 200, 60); this.add(titleLbl);

// 鼠标事件处理类 MouseEventListener mouseListener = new MouseEventListener(this); titleLbl.addMouseListener(mouseListener); titleLbl.addMouseMotionListener(mouseListener); this.setVisible(true); }

public static void main(String[] args) { new GuiHelloWorld(); } }

class MouseEventListener implements MouseInputListener { Point origin; // 鼠标拖拽想要移动的目标组件 GuiHelloWorld frame;

public MouseEventListener(GuiHelloWorld frame) { this.frame = frame; origin = new Point(); }

public void mouseClicked(MouseEvent e) { // TODO Auto-generated method stub

}

public void mousePressed(MouseEvent e) { // TODO Auto-generated method stub origin.x = e.getX(); origin.y = e.getY(); }

public void mouseReleased(MouseEvent e) { // TODO Auto-generated method stub

}

public void mouseEntered(MouseEvent e) { // TODO Auto-generated method stub this.frame.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR)); }

public void mouseExited(MouseEvent e) { // TODO Auto-generated method stub this.frame.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR)); }

public void mouseDragged(MouseEvent e) { // TODO Auto-generated method stub Point p = this.frame.getLocation(); this.frame.setLocation(p.x + (e.getX() - origin.x), p.y + (e.getY() - origin.y)); }

public void mouseMoved(MouseEvent e) { // TODO Auto-generated method stub

}

}