在这个SSCCE代码中：

这种方法工作

label.setForeground(Color.GREEN);

但下一个方法不行！

label.setBackground(Color.BLUE);

import java.awt.*;

import javax.swing.*;

public class LabelColorTest extends JPanel

{

static JLabel label;

JPanel panel;

public LabelColorTest()

{

label = new JLabel();

label.setVerticalAlignment(JLabel.CENTER);

label.setHorizontalAlignment(JLabel.CENTER);

label.setText("Hello world");

panel = new JPanel();

panel.setLayout(new BorderLayout());

panel.add(label, BorderLayout.CENTER);

label.setForeground(Color.GREEN); //HERE

label.setBackground(Color.BLUE); //HERE

this.setLayout(new BorderLayout());

this.add(panel);

}

private static void createAndShowGUI()

{

JFrame frame = new JFrame("Hellow world");

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setSize(400, 250);

frame.add(new LabelColorTest(), BorderLayout.CENTER);

frame.setVisible(true);

}

public static void main(String[] args)

{

SwingUtilities.invokeLater(new Runnable()

{

public void run()

{

UIManager.put("swing.boldMetal", Boolean.FALSE);

createAndShowGUI();

}

});

}

}

窗口背景颜色是指直接调用JFrame或者Frame的setBackground(Color color)方法设置后显示出来的颜色。如果直接调用这个方法后，的确设置了背景颜色，但看到的却不是直接的JFrame或者Frame，而是JFrame.getContentPane()，而JFrame上的contentPane默认是Color.WHITE的，所以，无论你对JFrame或者Frame怎么设置背景颜色，你看到的都只是contentPane.

解决方法：

办法A:在完成初始化，调用getContentPane()方法得到一个contentPane容器，然后将其设置为不可见，即setVisible(false)。

import javax.swing.*;

import java.awt.*

public class TestMenuBar1 {

public static void main(String arg[]) {

createNewMenu ck=new createNewMenu("第一个窗口");

}

}

class createNewMenu extends JFrame{

public createNewMenu(String title) {

getContentPane().setVisible(false);

setBackground(Color.blue); //设置窗口背景颜色

setTitle(title);

setBounds(200,200,500,500); //设置窗口位置和大小

setVisible(true); //设置窗口可见

}

}

办法B:直接加 this.getContentPane().setBackground(Color.blue);

import java.awt.*;

import javax.swing.*;

public class TestMenuBar1 {

public static void main(String arg[]) {

createNewMenu ck=new createNewMenu("第一个窗口");

}

}

class createNewMenu extends JFrame{

public createNewMenu(String title) {

setTitle(title);

setBounds(200,200,500,500);

setVisible(true);

this.getContentPane().setBackground(Color.blue);

}

}

这是Win32控制台的解决方案。

1)在这里获取JavaNativeAccess库：[https://github.com/twall/jna/]

2)这两个Java类将起到作用。

请享用。

package com.stackoverflow.util;

import com.sun.jna.Library;

import com.sun.jna.Native;

import com.sun.jna.Platform;

import com.sun.jna.Structure;

public class Win32 {

public static final int STD_INPUT_HANDLE = -10;

public static final int STD_OUTPUT_HANDLE = -11;

public static final int STD_ERROR_HANDLE = -12;

public static final short CONSOLE_FOREGROUND_COLOR_BLACK = 0x00;

public static final short CONSOLE_FOREGROUND_COLOR_BLUE = 0x01;

public static final short CONSOLE_FOREGROUND_COLOR_GREEN = 0x02;

public static final short CONSOLE_FOREGROUND_COLOR_AQUA = 0x03;

public static final short CONSOLE_FOREGROUND_COLOR_RED = 0x04;

public static final short CONSOLE_FOREGROUND_COLOR_PURPLE = 0x05;

public static final short CONSOLE_FOREGROUND_COLOR_YELLOW = 0x06;

public static final short CONSOLE_FOREGROUND_COLOR_WHITE = 0x07;

public static final short CONSOLE_FOREGROUND_COLOR_GRAY = 0x08;

public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_BLUE = 0x09;

public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_GREEN = 0x0A;

public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_AQUA = 0x0B;

public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_RED = 0x0C;

public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_PURPLE = 0x0D;

public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_YELLOW = 0x0E;

public static final short CONSOLE_FOREGROUND_COLOR_BRIGHT_WHITE = 0x0F;

public static final short CONSOLE_BACKGROUND_COLOR_BLACK = 0x00;

public static final short CONSOLE_BACKGROUND_COLOR_BLUE = 0x10;

public static final short CONSOLE_BACKGROUND_COLOR_GREEN = 0x20;

public static final short CONSOLE_BACKGROUND_COLOR_AQUA = 0x30;

public static final short CONSOLE_BACKGROUND_COLOR_RED = 0x40;

public static final short CONSOLE_BACKGROUND_COLOR_PURPLE = 0x50;

public static final short CONSOLE_BACKGROUND_COLOR_YELLOW = 0x60;

public static final short CONSOLE_BACKGROUND_COLOR_WHITE = 0x70;

public static final short CONSOLE_BACKGROUND_COLOR_GRAY = 0x80;

public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_BLUE = 0x90;

public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_GREEN = 0xA0;

public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_AQUA = 0xB0;

public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_RED = 0xC0;

public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_PURPLE = 0xD0;

public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_YELLOW = 0xE0;

public static final short CONSOLE_BACKGROUND_COLOR_BRIGHT_WHITE = 0xF0;

// typedef struct _COORD {

// SHORT X;

// SHORT Y;

// } COORD, *PCOORD;

public static class COORD extends Structure {

public short X;

public short Y;

}

// typedef struct _SMALL_RECT {

// SHORT Left;

// SHORT Top;

// SHORT Right;

// SHORT Bottom;

// } SMALL_RECT;

public static class SMALL_RECT extends Structure {

public short Left;

public short Top;

public short Right;

public short Bottom;

}

// typedef struct _CONSOLE_SCREEN_BUFFER_INFO {

// COORD dwSize;

// COORD dwCursorPosition;

// WORD wAttributes;

// SMALL_RECT srWindow;

// COORD dwMaximumWindowSize;

// } CONSOLE_SCREEN_BUFFER_INFO;

public static class CONSOLE_SCREEN_BUFFER_INFO extends Structure {

public COORD dwSize;

public COORD dwCursorPosition;

public short wAttributes;

public SMALL_RECT srWindow;

public COORD dwMaximumWindowSize;

}

// Source: https://github.com/twall/jna/nonav/javadoc/index.html

public interface Kernel32 extends Library {

Kernel32 DLL = (Kernel32) Native.loadLibrary("kernel32", Kernel32.class);

// HANDLE WINAPI GetStdHandle(

// __in DWORD nStdHandle

// );

public int GetStdHandle(

int nStdHandle);

// BOOL WINAPI SetConsoleTextAttribute(

// __in HANDLE hConsoleOutput,

// __in WORD wAttributes

// );

public boolean SetConsoleTextAttribute(

int in_hConsoleOutput,

short in_wAttributes);

// BOOL WINAPI GetConsoleScreenBufferInfo(

// __in HANDLE hConsoleOutput,

// __out PCONSOLE_SCREEN_BUFFER_INFO lpConsoleScreenBufferInfo

// );

public boolean GetConsoleScreenBufferInfo(

int in_hConsoleOutput,

CONSOLE_SCREEN_BUFFER_INFO out_lpConsoleScreenBufferInfo);

// DWORD WINAPI GetLastError(void);

public int GetLastError();

}

}

package com.stackoverflow.util;

import java.io.PrintStream;

import com.stackoverflow.util.Win32.Kernel32;

public class ConsoleUtil {

public static void main(String[] args)

throws Exception {

System.out.print("abc");

static_color_print(

System.out,

"def",

Win32.CONSOLE_BACKGROUND_COLOR_RED,

Win32.CONSOLE_FOREGROUND_COLOR_BRIGHT_WHITE);

System.out.print("def");

System.out.println();

}

private static Win32.CONSOLE_SCREEN_BUFFER_INFO _static_console_screen_buffer_info = null;

public static void static_save_settings() {

if (null == _static_console_screen_buffer_info) {

_static_console_screen_buffer_info = new Win32.CONSOLE_SCREEN_BUFFER_INFO();

}

int stdout_handle = Kernel32.DLL.GetStdHandle(Win32.STD_OUTPUT_HANDLE);

Kernel32.DLL.GetConsoleScreenBufferInfo(stdout_handle, _static_console_screen_buffer_info);

}

public static void static_restore_color()

throws Exception {

if (null == _static_console_screen_buffer_info) {

throw new Exception("Internal error: Must save settings before restore");

}

int stdout_handle = Kernel32.DLL.GetStdHandle(Win32.STD_OUTPUT_HANDLE);

Kernel32.DLL.SetConsoleTextAttribute(

stdout_handle,

_static_console_screen_buffer_info.wAttributes);

}

public static void static_set_color(Short background_color, Short foreground_color) {

int stdout_handle = Kernel32.DLL.GetStdHandle(Win32.STD_OUTPUT_HANDLE);

if (null == background_color || null == foreground_color) {

Win32.CONSOLE_SCREEN_BUFFER_INFO console_screen_buffer_info =

new Win32.CONSOLE_SCREEN_BUFFER_INFO();

Kernel32.DLL.GetConsoleScreenBufferInfo(stdout_handle, console_screen_buffer_info);

short current_bg_and_fg_color = console_screen_buffer_info.wAttributes;

if (null == background_color) {

short current_bg_color = (short) (current_bg_and_fg_color / 0x10);

background_color = new Short(current_bg_color);

}

if (null == foreground_color) {

short current_fg_color = (short) (current_bg_and_fg_color % 0x10);

foreground_color = new Short(current_fg_color);

}

}

short bg_and_fg_color =

(short) (background_color.shortValue() | foreground_color.shortValue());

Kernel32.DLL.SetConsoleTextAttribute(stdout_handle, bg_and_fg_color);

}

public static void static_color_print(

PrintStream ostream,

T value,

Short background_color,

Short foreground_color)

throws Exception {

static_save_settings();

try {

static_set_color(background_color, foreground_color);

ostream.print(value);

}

finally {

static_restore_color();

}

}

public static void static_color_println(

PrintStream ostream,

T value,

Short background_color,

Short foreground_color)

throws Exception {

static_save_settings();

try {

static_set_color(background_color, foreground_color);

ostream.println(value);

}

finally {

static_restore_color();

}

}

}