Question

我正在制作一个GUI，其中我有6个组合框，我从文本文件中读取数据到这些组合框。我的文本文件有3行2列，所以当我读取数据时，我的前2个组合框中的数据填充了文本文件的第3行而不是第1行的值，其余的组合框仍然存在我的文本文件包含6个值，它应该显示在6个组合框中。请帮助

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.util.*;

public class Read extends JPanel {
    public Read() {
        JPanel buttonPanel = new JPanel();
        add(buttonPanel);
        buttonPanel.setLayout(new GridLayout(0, 2, 5, 5));

        JComboBox comboBox1 = new JComboBox();
        comboBox1.addItem("1");
        comboBox1.addItem("2");
        comboBox1.addItem("4");

        JComboBox comboBox2 = new JComboBox();
        comboBox2.addItem("1");
        comboBox2.addItem("2");
        comboBox2.addItem("4");

        JComboBox comboBox3 = new JComboBox();
        comboBox3.addItem("1");
        comboBox3.addItem("2");
        comboBox3.addItem("4");

        JComboBox comboBox4 = new JComboBox();
        comboBox4.addItem("1");
        comboBox4.addItem("2");
        comboBox4.addItem("4");

        JComboBox comboBox5 = new JComboBox();
        comboBox5.addItem("1");
        comboBox5.addItem("2");
        comboBox5.addItem("4");

        JComboBox comboBox6 = new JComboBox();
        comboBox6.addItem("1");
        comboBox6.addItem("2");
        comboBox6.addItem("4");

        buttonPanel.add(comboBox1);
        buttonPanel.add(comboBox2);
        buttonPanel.add(comboBox3);
        buttonPanel.add(comboBox4);
        buttonPanel.add(comboBox5);
        buttonPanel.add(comboBox6);

        try{
            InputStream ips=new FileInputStream("tl.txt"); 
            InputStreamReader ipsr=new InputStreamReader(ips);
            BufferedReader br=new BufferedReader(ipsr);
            String line;
            while ((line=br.readLine())!=null) {
                String[] s = line.split(" ");
                comboBox1.setSelectedItem(s[0]);
                comboBox2.setSelectedItem(s[1]);
            }
            br.close(); 
        }       
        catch (Exception e){
            e.printStackTrace();
        }
    }
    public static void main(String[] args) {
        Read a = new Read();
        JFrame f = new JFrame("");
        f.getContentPane().add(a);
        f.setSize(300,200);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.pack();
        f.setVisible(true);
    }
}

文本文件

2 4
1 2
4 1

Answer 1

请查看您的代码，您只将数据填充到组合框1和2，其他组合框中您没有填写任何数据。

如果您想要其他组合框中的数据，请在while循环中填充它们。

希望这有帮助。

感谢

public class Read extends JPanel{

   String[] values=new String[6];
   JCombobox<String>[] combos=new JCombobox<String>[6];

   public Read() {

    //Do your layout initialization operations here

    this.initCombo();

    //Put the logic to add the comboboxes to the UI here

   }

   public void intiCombo(){
    try{
                ArrayList<String> tmp=new ArrayList<String>();
                InputStream ips=new FileInputStream("tl.txt"); 
                InputStreamReader ipsr=new InputStreamReader(ips);
                BufferedReader br=new BufferedReader(ipsr);
                String line;
                while ((line=br.readLine())!=null) {
                    String[] s = line.split(" ");
                    tmp.add(s[0]);
                    tmp.add(s[1]);
                }
                br.close(); 
            }       
            catch (Exception e){
                e.printStackTrace();
            }

         values=tmp.toArray(new String[1]);
         for(int i=0;i<conbos.length;i++)combos[i]=new JCombobox(values);

   }


    //Your main method comes here
}

Answer 2

声明一个JCombobox数组并将所有JCombobox存储在数组中，如下所示，

    JComboBox[] comboBoxs = new JComboBox[6];
    comboBoxs[0] = comboBox1;
    comboBoxs[1] = comboBox2;
    comboBoxs[2] = comboBox3;
    comboBoxs[3] = comboBox4;
    comboBoxs[4] = comboBox5;
    comboBoxs[5] = comboBox6;

声明Arraylist并存储您从文件中读取的数据，如下所示

// Other code goes here.
ArrayList<String> list = new ArrayList<String>();
String line;
    while ((line=br.readLine())!=null) {
        String[] s = line.split(" ");
        list.add(s[0]);
        list.add(s[1]);
    }
br.close();

最后循环遍历每个Arraylist并填充Combobox。

for(int i = 0; i < comboBoxs.length; i++) {
        comboBoxs[i].setSelectedItem(list.get(i));
    }

这应该做得很好。

从文件读取数据到JCombobox

2 个答案: