Question

为什么修改了GUI界面背景颜色在运行的时候还是白色了？要怎么改颜色了？

Answer 1

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.*;

public class Picture {
JTextField field,field1;
JTextArea textarea,textarea1;
public Picture(){
JFrame frame=new JFrame("ChatRoom");
frame.setSize(400,300);
textarea=new JTextArea();
textarea.setPreferredSize(new Dimension(100,100)); //添加的大小
textarea.setBackground(Color.green);//背景颜色
textarea.setEditable(false);
field=new JTextField();
field1=new JTextField();
//field1.setBounds(0, 0, 300, 40);因为布局管理器的问题所以这里没有到指定位置
textarea1=new JTextArea();
//textarea1.setBounds(300,50,100,200);同样
textarea1.setEditable(false);
textarea1.setBackground(Color.blue); //也是背景颜色
textarea1.setPreferredSize(new Dimension(100,100)); //大小
field.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {
//send the message when you input the enter when you compile the textarea
}

}); //匿名类实现发送
frame.getContentPane().add(new JScrollPane(textarea),"East");
frame.getContentPane().add(field,"South");
frame.getContentPane().add(field1,"North");
frame.getContentPane().add(textarea1,"West");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //hide the window when you click exit
frame.setVisible(true);
}
public static void main(String args[]){
new Picture();
}
}