JFrame显示透明图片与动态图片
一、介绍
最近发现桌面上显示的透明图片和动态图片看起来不错，于是研究了一下java能否做到这一点。使用JFrame基本是可以实现的，但是还有些缺陷。其中，核心语句是
jframe.setBackground(new Color(0,0,0,0));
jPanel.setBackground(new Color(0,0,0,0));
这两句都写上，才能实现透明图片的效果。
//网上说这句也可以：AWTUtilities.setWindowOpaque(frame, false);
//不过我加上不行，是jdk1.8不支持吗？还是win10下不支持呢？
直接上截图与代码了：
1.透明图片：
2.动态图片(gif)：
3.有问题的动态图片（本来应该是雪花效果的，要不不透明，要不就长这样，不会调了）：
二、代码
1.透明图片
import java.awt.*;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class noBankImg {
public static void main(String[] args) {
new noBankImg();
}
public noBankImg(){
start();
}
public static void start() {
final JFrame frame = new JFrame();
//设置在最顶层
frame.setAlwaysOnTop(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//设置隐藏标题栏与无法移动
frame.setUndecorated(true);
//禁止改变大小
frame.setResizable(false);
//设置出现位置
frame.setLocation(frame.getToolkit().getScreenSize().width-300, frame.getToolkit().getScreenSize().height-350);
//设置大小
frame.setSize(300, 300);
//这句不能用，无效，不兼容
//AWTUtilities.setWindowOpaque(frame, false);
//设置背景透明
frame.setBackground(new Color(0,0,0,0));
final JPanel pane = new JPanel() {
@Override
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
InputStream imgIS = this.getClass().getResourceAsStream("t3.png");
Image image = null;
try {
image = ImageIO.read(imgIS);
} catch (IOException e) {
e.printStackTrace();
}
g2d.drawImage(image, 0, 0,300,300, null);
}
};
//设置背景透明
pane.setBackground(new Color(0,0,0,0));
frame.setContentPane(pane);
//设置完毕后再显示
frame.setVisible(true);
}
}2.动态图片(图片原本是gif的，不过重命名成jpg也不影响)
import java.awt.*;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
//动图
public class t1 extends JFrame {
public t1() {
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setSize(400, 300);
//设置在最顶层
setAlwaysOnTop(true);
//设置出现位置
setLocation(getToolkit().getScreenSize().width-400, getToolkit().getScreenSize().height-350);
//设置隐藏标题栏与无法移动
setUndecorated(true);
//禁止改变大小
setResizable(false);
getContentPane().setLayout(null);
JPanel panel = new ImagePanel();
panel.setBounds(0, 0, 400, 300);
//设置背景透明
setBackground(new Color(0,0,0,0));
//panel.setBackground(new Color(0,0,0,0));
getContentPane().add(panel);
setVisible(true);
}
public static void main(String[] args) {
new t1();
}
class ImagePanel extends JPanel {
public void paint(Graphics g) {
super.paint(g);
ImageIcon icon = new ImageIcon(this.getClass().getResource("t5.jpg"));
g.drawImage(icon.getImage(), 0, 0, 400, 300, this);
}
}
}3.有问题的动态图片
import com.sun.awt.AWTUtilities;
import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.io.IOException;
import java.io.InputStream;
//pane.setBackground(new Color(0,0,0,0));
//AWTUtilities.setWindowOpaque(frame, false);
public class t3 {
public static void main(String[] args) {
new t3();
}
public t3(){
start();
}
public static void start() {
final JFrame frame = new JFrame();
frame.setAlwaysOnTop(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setUndecorated(true);
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
//这句不能用，无效，不兼容
//AWTUtilities.setWindowOpaque(frame, false);
frame.setBackground(new Color(0,0,0,0));
final JPanel pane = new JPanel() {
private int[] snowX = null;
private int[] snowY = null;
private int[] angles = null;
private int count = 50;
@Override
public void paint(Graphics g) {
super.paint(g);
Rectangle bounds = frame.getBounds();
if (snowX == null) {
snowX = new int[count];
for (int i = 0; i < snowX.length; i++) {
snowX[i] = getRandomInt(bounds.width);
}
snowY = new int[count];
for (int i = 0; i < snowY.length; i++) {
snowY[i] = getRandomInt(bounds.height);
}
angles = new int[count];
for (int i = 0; i < snowY.length; i++) {
angles[i] = getRandomInt(360);
}
}
Graphics2D g2d = (Graphics2D) g;
InputStream imgIS = this.getClass().getResourceAsStream("t3.png");
Image image = null;
try {
image = ImageIO.read(imgIS);
} catch (IOException e) {
e.printStackTrace();
}
for (int i = 0; i < count; i++) {
snowX[i] += getRandomInt(5) - 3;
snowY[i] += 5;
angles[i] += i / 5;
snowY[i] = snowY[i] > bounds.height ? 0 : snowY[i];
angles[i] = angles[i] > 360 ? 0 : angles[i];
int x = snowX[i];
int y = snowY[i];
int angle = angles[i];
g2d.translate(x, y);
double angleValue = Math.toRadians(angle);
g2d.rotate(angleValue);
g2d.drawImage(image, 0, 0, null);
g2d.rotate(-angleValue);
g2d.translate(-x, -y);
}
}
};
//设置透明背景
pane.setBackground(new Color(0,0,0,0));
frame.setContentPane(pane);
frame.setVisible(true);
Thread thread = new Thread() {
@Override
public void run() {
while (true) {
try {
Thread.sleep(10);
} catch (Exception ex) {
ex.printStackTrace();
}
pane.repaint();
}
}
};
thread.start();
}
public static int getRandomInt(int width) {
int i = 0;
double d = Math.random() * width;
i = (int)d;
return i;
}
}
三、说明
以上代码可以直接使用。
有问题的动态图片的代码，还请大佬看看怎么优化；要不实现不了透明效果，要不就是那样，有重叠，很尴尬。