import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;public class Ex32 extends Applet implements MouseListener { Label msg = new Label("", Label.CENTER); public void init() {
add(msg);
} String tempString = "asdfg";
public void mouseClicked(MouseEvent e) {}
public void mousePressed(MouseEvent e) {//按下鼠标使显示
msg.setText(tempString);
}
public void mouseReleased(MouseEvent e) {//松开鼠标是不显示
msg.setText("");
}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}}
import java.awt.*;
import java.awt.event.*;public class Ex32 extends Applet implements MouseListener { Label msg = new Label("", Label.CENTER); public void init() {
add(msg);
} String tempString = "asdfg";
public void mouseClicked(MouseEvent e) {}
public void mousePressed(MouseEvent e) {//按下鼠标使显示
msg.setText(tempString);
}
public void mouseReleased(MouseEvent e) {//松开鼠标是不显示
msg.setText("");
}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}}
add(msg);
addMouseListener(this);
}
没有添加监听,当然不管用
还是有个问题msg.addMouseListener(this); 这样添加侦听为什么不行呢?
public void init(){
add(msg);
msg.addMouseListener(this);
msg.setBackground(Color.red);
}
import java.awt.event.*;
import java.awt.Font;
import java.awt.Color;
import java.applet.Applet;
import java.awt.Graphics;public class App extends Applet implements MouseListener {
Color tColor;
String tString;
String text;
public void init() {
tString = getParameter("COLOR");
text = getParameter("TEXT");
if (tString.equals("BLUE"))
tColor = new Color(0, 0, 255);
addMouseListener(this);
}
public void paint(Graphics g) {
g.setColor(tColor);
g.drawString("text", 10, 20);
}
public void mouseClicked(MouseEvent e) {}
public void mousePressed(MouseEvent e) {
text = getParameter("TEXT");
repaint(); }
public void mouseReleased(MouseEvent e) {
text = "";
repaint();
}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}}
他总是提醒说 小程序没有初始化 为什么呢?