Question

我只是使用事件处理程序在Java中编写基本的GUI程序。所有代码都正常工作，除了

上的一点错误

string s = String.format("field 1 is %s", event.getActionCommand())

错误是

String类型的方法格式（String，object）不适用于参数format（String，String）`＆＃39;。

所以event.getActionCommand())肯定会返回一个字符串。但格式方法不接受。

我在eclipse（kepler）中使用着名的互联网教程之一来做这个代码。他的代码有效，但不是我的。我是Java的初学者。请帮我找到这个愚蠢的错误。

这是我的代码。

package tushar_GUI;

import java.awt.FlowLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.JPasswordField;

public class tush extends JFrame{

private JTextField textbox1;
private JTextField textbox2;
private JTextField textbox3 ;
private JPasswordField textbox_pass1;

public tush(){
    super("TITLE");
    setLayout(new FlowLayout());

    textbox1 = new JTextField(10);
    add(textbox1);

    textbox2 = new JTextField("Enter Your Text Here", 30);
    add(textbox2);

    textbox3 = new JTextField("This is UNEDITABLE textbox", 30);
    textbox3.setEditable(false);
    add(textbox3);

    textbox_pass1 = new JPasswordField("password");
    add(textbox_pass1);

    thehandler handler = new thehandler();
    textbox1.addActionListener(handler);
    textbox2.addActionListener(handler);
    textbox3.addActionListener(handler);
    textbox_pass1.addActionListener(handler);

}

private class thehandler implements ActionListener{

    public void actionPerformed(ActionEvent event){

        String string = "";

        if(event.getSource() == textbox1)
            string = String.format("field 1 is %s",     event.getActionCommand());
        else if(event.getSource() == textbox2)
            string = String.format("field 2 is %s",     event.getActionCommand());
        else if(event.getSource() == textbox3)
            string = String.format("field 3 is %s",     event.getActionCommand());
        else if(event.getSource() == textbox_pass1)
            string = String.format("password field is %s",     event.getActionCommand());

        JOptionPane.showMessageDialog(null, string);
    }
}

}

这是我的主要课程

package tushar_GUI;

import javax.swing.JFrame;

public class gui1 {

public static void main (String[] args){

    tush tushObject = new tush();
    tushObject.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    tushObject.setSize(500, 500);
    tushObject.setVisible(true);
}
}

Answer 1

您尚未在文本框中添加操作命令

溶液：

textbox1 = new JTextField(10);
textbox1.setActionCommand("textbox1 ");
add(textbox1);

textbox2 = new JTextField("Enter Your Text Here", 30);
textbox2.setActionCommand("textbox2 ");
add(textbox2);

textbox3 = new JTextField("This is UNEDITABLE textbox", 30);
textbox3.setActionCommand("textbox3 ");
textbox3.setEditable(false);

错误：String.format不接受event.getActionCommand（）[作为对象]

1 个答案: