多个事件源addActionListener,如何区别是哪个事件源发生事件并做不同的处理?

Question

我想实现,按button1,TextField中显示1,
按button2,TextField中显示2,
按button3,TextField中显示3,
按button4,TextField中显示4,
按button5,TextField中显示5,
我的代码:
import java.awt.*;
import java.awt.event.*;
public class MyGridLayout1 extends Frame
{
        private String[] name={"0","1","2","3","4","5",
        "6","7","8","9","+","-","*","/",".","=","?"};
        private Button[] btn= new Button[name.length];
        private TextField tf= new TextField();        public MyGridLayout1()
        {
                super("GridLayoutDemo");
                setLayout(new GridLayout(3,6,4,4));
                add(tf);
                for(int i = 0;i<name.length;i++)
                {
                        btn=new Button(name[i]);
                        this.add(btn[i]);
                }
                setSize(250,150);
                show();
            for(int i = 0;i<name.length;i++)          
                   {        
                         btn[i].addActionListener(new BtnListener());        
                   }        
          
        }
        class BtnListener implements ActionListener
        {
                public void actionPerformed(ActionEvent e)
                {
                //}[i]这里怎么区别是不同按钮的事件?
                }
        }
        public static void main(String[] args)
    {
      new MyGridLayout1();
      
    }                
                
                
                
刚学事件处理,请同行大哥帮忙

Answer 1

import java.awt.*;
import java.awt.event.*;
public class MyGridLayout1 extends Frame
{
        private String[] name={"0","1","2","3","4","5",
        "6","7","8","9","+","-","*","/",".","=","?"};
        private Button[] btn= new Button[name.length];
        private TextField tf= new TextField();        public MyGridLayout1()
        {
                super("GridLayoutDemo");
                setLayout(new GridLayout(3,6,4,4));
                add(tf);
                for(int i = 0;i<name.length;i++)
                {
                        btn=new Button(name[i]);
                        this.add(btn[i]);
                }
                setSize(250,150);
                show();
            for(int i = 0;i<name.length;i++)          
                   {        
                         btn[i].addActionListener(new BtnListener());
                         btn[i].addActionCommand(name[i]);        
                   }        
          
        }
        class BtnListener implements ActionListener
        {
                public void actionPerformed(ActionEvent e)
                {
                String command=e.getActionCommand();                
                if (command.equals(name[1])){
                   按钮1事件处理                
                }else if (command.equals(name[2])){{
                按钮2事件处理                
                }
                .....
                //}[i]这里怎么区别是不同按钮的事件?
                }
        }
        public static void main(String[] args)
    {
      new MyGridLayout1();
      
    }

Answer 2

public void actionPerformed(ActionEvent e)
 {
    Button tempButton= (Button)e.getSource();
    System.out.println(menuItem.getName());
String strTemp = menuItem.getName();
    可以根据button的名字来区别，当然还有其它方法 }

Answer 3

public void actionPerformed(ActionEvent e)
 {
    Button tempButton= (Button)e.getSource();
    System.out.println(tempButton.getName());
String strTemp = tempButton.getName();
    可以根据button的名字来区别，当然还有其它方法 }上面的写错啦,看这个 

Answer 4

有getSource().equals也可以
谢谢
已解决,帖出代码
import java.awt.*;
import java.awt.event.*;
public class MyGridLayout1 extends Frame
{
private String[] name={"0","1","2","3","4","5",
"6","7","8","9","+","-","*","/",".","=","?"};
private Button[] btn= new Button[name.length];
private TextField tf= new TextField(); public MyGridLayout1()
{
super("GridLayoutDemo");
setLayout(new GridLayout(3,6,4,4));



add(tf);


for(int i = 0;i<name.length;i++)
{
btn[i]=new Button(name[i]);
this.add(btn[i]);
}
setSize(250,150);
show();
    for(int i = 0;i<name.length;i++)          
        {        
         btn[i].addActionListener(new BtnListener());        
        } 
        
       this.addWindowListener(new WindowAdapter(){
        public void windowClosing(WindowEvent e){
         closeWindow();
        }
        });        
  
}
class BtnListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
/* if (e.getSource().equals(btn[1]))
{
tf.setText("1");
}*/
for(int i = 0;i<10;i++)
{
if (e.getSource().equals(btn[i]))
{

tf.setText(new Integer(i).toString());
}

}
if (e.getSource().equals(btn[10]))
{
tf.setText("+");
}
else if(e.getSource().equals(btn[11]))
{
tf.setText("-");
}
else if(e.getSource().equals(btn[12]))
{
tf.setText("*");
}

else if(e.getSource().equals(btn[13]))
{
tf.setText("/");
}

else if(e.getSource().equals(btn[14]))
{
tf.setText(".");
}

else if(e.getSource().equals(btn[15]))
{
tf.setText("=");
}
else if(e.getSource().equals(btn[16]))
{
tf.setText("?");
}


}
}
public void closeWindow()
{
System.exit(0);
}
public static void main(String[] args)
    {
      new MyGridLayout1();
      
    }
}

Answer 5

这个计算器的代码可能对你有用
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;public class Calculator extends JFrame { private Container container;
private GridBagLayout layout;
private GridBagConstraints constraints; 
private JTextField displayField;//计算结果显示区
private String lastCommand;//保存+,-,*,/,=命令
private double result;//保存计算结果
private boolean start;//判断是否为数字的开始 public Calculator() { super("Calculator");
container=getContentPane();
layout=new GridBagLayout();
container.setLayout(layout);
constraints=new GridBagConstraints();
start=true;
result=0;
lastCommand = "=";
displayField=new JTextField(20);
displayField.setHorizontalAlignment(JTextField.RIGHT);
constraints.gridx=0;
constraints.gridy=0;
constraints.gridwidth=4;
constraints.gridheight=1;
constraints.fill=GridBagConstraints.BOTH;
constraints.weightx=100;
constraints.weighty=100;
layout.setConstraints(displayField,constraints);
container.add(displayField);
ActionListener insert = new InsertAction();
ActionListener command = new CommandAction();
addButton("Backspace",0,1,2,1,insert);
addButton("CE",2,1,1,1,insert);
addButton("C",3,1,1,1,insert);
addButton("7",0,2,1,1,insert);
addButton("8",1,2,1,1,insert);
addButton("9",2,2,1,1,insert);
addButton("/",3,2,1,1,command);
addButton("4",0,3,1,1,insert);
addButton("5",1,3,1,1,insert);
addButton("6",2,3,1,1,insert);
addButton("*",3,3,1,1,command);
addButton("1",0,4,1,1,insert);
addButton("2",1,4,1,1,insert);
addButton("3",2,4,1,1,insert);
addButton("-",3,4,1,1,command);
addButton("0",0,5,1,1,insert);
addButton("+/-",1,5,1,1,insert);//只显示"-"号,"+"没有实用价值
addButton(".",2,5,1,1,insert);
addButton("+",3,5,1,1,command);
addButton("=",0,6,4,1,command);
setSize(300,300);
setVisible(true);

}
private void addButton(String label,int row,int column,int with,int height,ActionListener listener) { JButton button=new JButton(label);
constraints.gridx=row;
constraints.gridy=column;
constraints.gridwidth=with;
constraints.gridheight=height;
constraints.fill=GridBagConstraints.BOTH;
button.addActionListener(listener);
layout.setConstraints(button,constraints);
container.add(button);
}
private class InsertAction implements ActionListener { public void actionPerformed(ActionEvent event) { String input=event.getActionCommand();
if (start) {
displayField.setText("");
start=false;
if(input.equals("+/-"))
displayField.setText(displayField.getText()+"-"); 
}

if(!input.equals("+/-")) {
if(input.equals("Backspace")) {
String str=displayField.getText();
if(str.length()>0)
  displayField.setText(str.substring(0,str.length()-1));
}else if(input.equals("CE")||input.equals("C")) {
displayField.setText("0");
start=true;
}else
displayField.setText(displayField.getText()+input);
}
}
}
private class CommandAction implements ActionListener { public void actionPerformed(ActionEvent evt) {
String command=evt.getActionCommand();
if(start) {
lastCommand=command;
}else {
calculate(Double.parseDouble(displayField.getText()));
lastCommand=command;
start=true;
}
}
} public void calculate(double x) {
if (lastCommand.equals("+")) result+= x;    
else if (lastCommand.equals("-")) result-=x;
else if (lastCommand.equals("*")) result*=x;   
else if (lastCommand.equals("/")) result/=x;
else if (lastCommand.equals("=")) result=x;
displayField.setText(""+ result);
} public static void  main(String []args) {
Calculator calculator=new Calculator();
calculator.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}}