Description: According to the video link written in the video of learning station b [Mad God speaks java]
Case 1
package bili_02;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
//ActionListener是一个接口
class MyActionListener implements ActionListener{
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
System.out.println("点击了btn");
}
}
public class TestAction {
public static void main(String[] args) {
//按下按钮，触发一些事件
Frame frame = new Frame("事件监听窗口");
Button btn = new Button("btn");
//因为addActionListener()需要一个ActionListener,所以我们需要构造一个ActionListener
MyActionListener myActionListener = new MyActionListener();
btn.addActionListener(myActionListener);
frame.add(btn);
//自适应大小
frame.setSize(200, 100);
frame.setVisible(true);
windowClosing(frame);
}
//关闭窗口的事件
public static void windowClosing(Frame frame) {
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
}
}
operation result:
Case 2
Two buttons share one monitor
package bili_02;
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Frame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
class MyMonitor implements ActionListener{
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
System.out.println("点击了"+e.getActionCommand());
if(e.getActionCommand().equals("start")) {
}
}
}
public class TestActionListener {
public static void main(String[] args) {
//两个按钮，实现一个监听
//开始 结束
Frame frame = new Frame("开始-结束");
Button btn1 = new Button("start");
Button btn2 = new Button("stop");
frame.add(btn1,BorderLayout.NORTH);
frame.add(btn2,BorderLayout.SOUTH);
frame.setSize(200,100);
//设置显示内容
btn2.setActionCommand("btn2-stop");
MyMonitor myMonitor = new MyMonitor();
btn1.addActionListener(myMonitor);
btn2.addActionListener(myMonitor);
windowClosing(frame);
frame.setVisible(true);
}
public static void windowClosing(Frame frame) {
frame.addWindowListener((WindowListener) new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
}
}
The results of the operation are:
Case 3
Input text box monitoring, input text box cannot wrap, text field can wrap
package bili_03;
import java.awt.*;
import java.awt.event.*;
class MyFrame extends Frame {
public MyFrame() {
TextField textField = new TextField();
add(textField);
pack();
// 监听这个文本框输入的文字
MyActionListener myActionListener = new MyActionListener();
// 按下enter 会触发这个输入框的事件
textField.addActionListener(myActionListener);
// 设置替换编码 输入的字符显示为*
textField.setEchoChar('*');
setVisible(true);
}
}
class MyActionListener implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
// 在监听器中拿到了TextField对象，然后借用TextField对象的方法获得文本
TextField field = (TextField) e.getSource(); // 获得一些资源,返回一个对象
System.out.println(field.getText()); // 获得输入框的文本
field.setText(""); // 按下enter之后清空
}
}
public class TestText {
public static void main(String[] args) {
MyFrame myFrame = new MyFrame();
windowClosing(myFrame); //关闭
}
//监听关闭事件
public static void windowClosing(Frame frame) {
frame.addWindowListener((WindowListener) new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
}
}
The results of the operation are as follows:
