javajpanel背景

① 在java中怎么样设置JPanel里面的背景图片

java要加背景图比较麻烦,需要重载paintComponent方法,下面以JPanel为例,其它按此继承就可
JPanel jContentPane = new getpane(800,600,"images\\0044.jpg");
jContentPane.setLayout(null);
jContentPane.setOpaque(false);//此处要设为false
jContentPane.setAlignmentY(0.5F);
jContentPane.add(jLabel, null);
jContentPane.add(getJTestYear(), null);
this.initComboBox();
jContentPane.add(getJSearchByName(), null);
jContentPane.add(getJSearchByID(), null);
jContentPane.add(getJIDOrName(), null);
jContentPane.add(jLabel1, null);
jContentPane.add(getJPanel(), null);
this.setContentPane(jContentPane);

class getpane extends JPanel{
private static final long serialVersionUID = 1L;
int width=0,hight=0;
String imgpath = "";
public getpane(int width,int hight,String file){
this.width = width;
this.hight = hight;
imgpath = file;
}
protected void paintComponent(Graphics g) {
ImageIcon icon = new ImageIcon(imgpath);
Image img = icon.getImage();
g.drawImage(img, 0, 0, width, hight, this);
}

}

② java中使用Eclipse怎么把JPanel的背景色设置成透明的

JPanel buttonPanel = new JPanel();
buttonPanel.setBackground(null); // 把背景设置为会
buttonPanel.setOpaque(false); // 设置为透明

③ java中jpanel的背景图片问题

写一个ImageJPanel类继承自JPanel,在paintComponent方法中用g.drawImage绘制Image背景图片就挡不着第一张卡片上的四个按钮了。

完整的程序如下：(注意把背景图片的路径换成你的背景图片路径)

importjava.awt.CardLayout;
importjava.awt.Color;
importjava.awt.Graphics;
importjava.awt.GridLayout;
importjava.awt.Image;
importjava.awt.Toolkit;
importjava.awt.event.ActionEvent;
importjava.awt.event.ActionListener;
importjavax.swing.JButton;
importjavax.swing.JFrame;
importjavax.swing.JPanel;
importjavax.swing.JSplitPane;
{
=1L;
JPaneljp1=newJPanel();
JPaneltmpjp1=newJPanel();
JPaneljp2=newJPanel();
JPanelcard_jp1=newJPanel();
JPanelcard_jp2=newJPanel();
JPanelcard_jp3=newJPanel();
JPanelcard_jp4=newJPanel();
JButtonjb1=newJButton("按钮1");
JButtonjb2=newJButton("按钮2");
JButtonjb3=newJButton("按钮3");
JButtonjb4=newJButton("按钮4");
JSplitPanejsp=newJSplitPane(JSplitPane.HORIZONTAL_SPLIT,jp1,jp2);
CardLayoutcl=newCardLayout();
intj=1;
D(){
tmpjp1.setLayout(newGridLayout(4,1,5,5));
tmpjp1.add(jb1);tmpjp1.add(jb2);tmpjp1.add(jb3);tmpjp1.add(jb4);
jp1.add(tmpjp1);
jp2.setLayout(cl);
JPanelp[]=newJPanel[4];
p[0]=newImageJPanel();
jp2.add(p[0],String.valueOf(0));
for(inti=1;i<4;i++){
p[i]=newJPanel();
jp2.add(p[i],String.valueOf(i));
}
JButtonb[]=newJButton[4];
for(inti=1;i<4;i++){
inta=i+1;
b[i]=newJButton("第"+a+"页,下一页");
b[i].addActionListener(this);
p[i].add(b[i]);
}
jsp.setResizeWeight(0.3);
add(jsp);
setSize(800,500);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
}

publicstaticvoidmain(String[]args){
newD();
}
@Override
publicvoidactionPerformed(ActionEvente){
cl.show(jp2,String.valueOf(j++));
if(j==4)j=0;
}
classImageJPanelextendsJPanel{
privateImageimage;
JButtoncard_jb1=newJButton("按钮1");
JButtoncard_jb2=newJButton("按钮2");
JButtoncard_jb3=newJButton("按钮3");
JButtonjb=newJButton("第1页,下一页");
publicImageJPanel(){
super();
setOpaque(true);
add(card_jb1);
add(card_jb2);
add(card_jb3);
jb.addActionListener(newActionListener(){
@Override
publicvoidactionPerformed(ActionEvente){
cl.show(jp2,String.valueOf(j++));
if(j==4)j=0;
}
});
add(jb);
image=Toolkit.getDefaultToolkit().getImage("C:/tmp/F/3.jpg");//这里换成你的背景图片地址
}
publicvoidpaintComponent(Graphicsg){
super.paintComponent(g);
setBackground(Color.WHITE);
if(image!=null){
intheight=image.getHeight(this);
intwidth=image.getWidth(this);
if(height!=-1&&height>getHeight())
height=getHeight();
if(width!=-1&&width>getWidth())
width=getWidth();
intx=(int)(((double)(getWidth()-width))/2.0);
inty=(int)(((double)(getHeight()-height))/2.0);
g.drawImage(image,x,y,width,height,this);
}
}
}
}

④ JAVA 的JPanel 设置背景求解

你的this的布局是不是null啊、如果是null，就看不到
你可以设置borderlayout，就可以看到了，他就在中间

⑤ 在java中怎么样设置JPanel里面的背景图片

java要加背景图比较麻烦,需要重载paintComponent方法,下面以JPanel为例,其它按此继承就可 JPanel jContentPane = new getpane(800,600,"images\\0044.jpg"); jContentPane.setLayout(null); jContentPane.setOpaque(false);//此处要设为false jContentPane.setAlignmentY(0.5F); jContentPane.add(jLabel, null); jContentPane.add(getJTestYear(), null); this.initComboBox(); jContentPane.add(getJSearchByName(), null); jContentPane.add(getJSearchByID(), null); jContentPane.add(getJIDOrName(), null); jContentPane.add(jLabel1, null); jContentPane.add(getJPanel(), null); this.setContentPane(jContentPane); class getpane extends JPanel{ private static final long serialVersionUID = 1L; int width=0,hight=0; String imgpath = ""; public getpane(int width,int hight,String file){ this.width = width; this.hight = hight; imgpath = file;}protected void paintComponent(Graphics g) {

⑥ Java swing JPanel背景颜色边框显示问题 实现多个JPanel的无缝连接

你使用的是TitleBorder，是带边框的，背景色不会改变边框的颜色。要么设置EmptyBorder，要么改变边框颜色。

⑦ java中如何在JPanel里设置背景

使用成员函数setBackground(Color bg)，下面是java文档中对该方法的说明。
public void setBackground(Color bg)
Sets the background color of this component. The background color is used only if the component is opaque, and only by subclasses of JComponent or ComponentUI implementations. Direct subclasses of JComponent must override paintComponent to honor this property.
It is up to the look and feel to honor this property, some may choose to ignore it.

⑧ JAVA怎样让JLabel透明，显示出下面的JPanel背景

import javax.swing.*;

import java.awt.*;

public class BackGround extends JFrame {
Container content;
Toolkit toolkit;
JLabel bkLabel = new JLabel(); // 背景图片标签
JLabel horseLabel = new JLabel();
JButton bButton;
int screenWidth, screenHeight, WIDTH, HEIGHT;
ImageIcon backImage, bImage;
BackGround() {
content = getContentPane();
toolkit = Toolkit.getDefaultToolkit();
screenWidth = toolkit.getScreenSize().width;
screenHeight = toolkit.getScreenSize().height;
bImage = new ImageIcon("pic/logo.jpg");
//我的笨方法
JLabel image_lab = new JLabel(new ImageIcon("D:\\pic\\logo.jpg"));
//编译的时候会帮你把文件拷贝到classes目录下面去
//同时要达到LZ的效果很简单，两个Panel。直接覆盖的话，如果覆盖面板小于底层面板，当鼠标移动到底层面板区域。则显示了，所以建议加上 //setEnabled(false);这样做LZ你不觉得复杂了吗？你直接在我的image_lab 上加载组件不行吗？或者你先都把组件隐藏了，等用户触发事件再显//示也可以啊。
//
backImage = new ImageIcon("pic/background.gif");
bkLabel.setIcon(backImage);
bkLabel.setOpaque(true);
WIDTH = backImage.getIconWidth();
HEIGHT = backImage.getIconHeight();
content.add(bkLabel, -1); // 添加背景图片
bButton = new JButton(bImage);
JPanel panel2 = new JPanel();
panel2.setOpaque(false); // 设置panel2背景透明
panel2.setPreferredSize(new Dimension(40, 40));
panel2.add(bButton);
content.add(panel2);
validate();
setBounds(300, 200, WIDTH, HEIGHT);
setLocation((screenWidth - WIDTH) / 2, (screenHeight - HEIGHT) / 2);
setSize(WIDTH, HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}

public static void main(String[] args)
{
new BackGround();
}
}

⑨ java swing 的jPanel背景颜色能否设置为透明,代码怎么写

设置颜色：
把pan - pan6的Background设为Null，这样他们就变为透明的了，以后只需要改变inquestFrame的颜色就可以改变全部的颜色，代码如下：
// 设置整体布局
JPanel pan = new JPanel();
pan.setLayout(new GridLayout(6, 1));
pan.add(pan1);
pan.add(pan2);
pan.add(pan3);
pan.add(pan4);
pan.add(pan5);
pan.add(pan6);
pan.setBackground(null);
pan1.setBackground(null);
pan2.setBackground(null);
pan3.setBackground(null);
pan4.setBackground(null);
pan5.setBackground(null);
pan6.setBackground(null);
r1.setBackground(null);
r2.setBackground(null);
inquestFrame.setBackground(Color.LIGHT_GRAY);
inquestFrame.setContentPane(pan);
inquestFrame.setSize(300, 250);
inquestFrame.setVisible(true);

设置图片需要改的比较多，自己比较那不一样吧：
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.URL;

import javax.swing.ButtonGroup;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JTextField;

public class Inquest {
JFrame inquestFrame;
JLabel lab1, lab2, lab3, lab4, lab5, lab6;
JTextField text1, text2, text4, text5, text6;
JRadioButton r1, r2;
JButton inqButton;

public Inquest() {
inquestFrame = new JFrame("教育经历管理系统-查询窗口");
MyPanel pan1 = new MyPanel();
lab1 = new JLabel("请输入编码:");
text1 = new JTextField(10);
inqButton = new JButton(" 查询");
inqButton.addActionListener(new ButtonHandler());
pan1.add(lab1);
pan1.add(text1);
pan1.add(inqButton);

MyPanel pan2 = new MyPanel();
lab2 = new JLabel("姓名:");
text2 = new JTextField(10);
pan2.add(lab2);
pan2.add(text2);

MyPanel pan3 = new MyPanel();
lab3 = new JLabel("性别:");
r1 = new JRadioButton("男");
r2 = new JRadioButton("女");
// 把两个单选按钮放到一个群组中，保持二选一
ButtonGroup group = new ButtonGroup();
group.add(r1);
group.add(r2);

pan3.add(lab3);
pan3.add(r1);
pan3.add(r2);
MyPanel pan4 = new MyPanel();
lab4 = new JLabel("单位:");
text4 = new JTextField(10);
pan4.add(lab4);
pan4.add(text4);

MyPanel pan5 = new MyPanel();
lab5 = new JLabel("职位:");
text5 = new JTextField(10);
pan5.add(lab5);
pan5.add(text5);

MyPanel pan6 = new MyPanel();
lab6 = new JLabel("年龄:");
text6 = new JTextField(10);
pan6.add(lab6);
pan6.add(text6);

// 设置整体布局
MyPanel pan = new MyPanel();
pan.setLayout(new GridLayout(6, 1));
pan.add(pan1);
pan.add(pan2);
pan.add(pan3);
pan.add(pan4);
pan.add(pan5);
pan.add(pan6);
pan.setBackground(null);
pan1.setBackground(null);
pan2.setBackground(null);
pan3.setBackground(null);
pan4.setBackground(null);
pan5.setBackground(null);
pan6.setBackground(null);
r1.setBackground(null);
r2.setBackground(null);

MyPanel pan0 = new MyPanel();
pan0.setPreferredSize(pan.getPreferredSize());
pan0.setLayout(null);
pan.setBounds(0, 0, pan.getPreferredSize().width, pan.getPreferredSize().height);
URL url = Inquest.class.getResource("Winter.jpg");
ImageIcon img = new ImageIcon(url);
JLabel lab = new JLabel(img);
lab.setBounds(0, 0, img.getIconWidth(), img.getIconHeight());
pan0.add(pan);
pan0.add(lab);
inquestFrame.setContentPane(pan0);
inquestFrame.pack();
inquestFrame.setVisible(true);

}

public static class MyPanel extends JPanel {
public void paint(Graphics g) {
paintChildren(g);
}
}

public void setBack() {
((JPanel) inquestFrame.getContentPane()).setOpaque(false);
// Winter.jpg这个图片的位置要跟当前这个类是同一个包下
URL url = Inquest.class.getResource("Winter.jpg");
ImageIcon img = new ImageIcon(url);

JLabel background = new JLabel(img);
inquestFrame.getLayeredPane().add(background, new Integer(Integer.MIN_VALUE));
background.setBounds(0, 0, img.getIconWidth(), img.getIconHeight());
}

class ButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e) {

// 生成SQL语句
String s = "select * from information where id=" + "'" + text1.getText() + "'";

String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
String url = "jdbc:odbc:test";

// DB db = new DB(driver, url, "sa", "");
// ResultSet rs = db.query(s);
// try {
// while (rs.next()) {
// text2.setText(rs.getString(2));
// String sex = rs.getString(3);
// if (sex.trim().equals("男"))
// r1.setSelected(true);
// else
// r2.setSelected(true);
//
// text4.setText(rs.getString(4));
// text5.setText(rs.getString(5));
// text6.setText(rs.getString(6));
// }
// } catch (Exception e2) {
// e2.printStackTrace();
// }

}
}

public static void main(String args[]) {
new Inquest();
}

}