1. 使JDialog位于屏幕的中央
public void setToScreenCenter(JDialog jd) {
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); Dimension frameSize = jd.getSize(); if (frameSize.height > screenSize.height) { frameSize.height = screenSize.height; } if (frameSize.width > screenSize.width) { frameSize.width = screenSize.width; } jd.setLocation((screenSize.width - frameSize.width) / 2,(screenSize.height - frameSize.height) / 2); }2.为JDialog增加图片背景
public class MySwingTest extends JDialog{
private JPanel panelContent; private BufferedImage image; private Graphics g; private Image srcImage; String imageURL = "C:/NMS/PLATFORM/NNM5/client/resource/symbols/background/background.gif"; public MySwingTest(){ image = new BufferedImage(1200, 760, BufferedImage.TYPE_3BYTE_BGR); image.flush(); g = image.getGraphics(); try { srcImage = ImageIO.read(new File(imageURL)); } catch (IOException e) { e.printStackTrace(); } g.drawImage(srcImage,0,0, null); init(); }private void init(){
this.setMinimumSize(new Dimension(700, 560)); this.setMaximumSize(new Dimension(700, 560)); /*try {//这样加载的是一个图片，而不是将图片作为背景 ImageIcon icon = new ImageIcon(image); JLabel label = new JLabel(icon); label.setBounds(0, 0, icon.getIconWidth(), icon.getIconHeight()); panelContent.add(label); g.dispose(); }catch (Exception e) { e.printStackTrace(); }*/ panelContent = new NewPanel(); this.setContentPane(panelContent); this.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE); setToScreenCenter(this); this.setVisible(true); }public void setToScreenCenter(JDialog jd) {//上面的方法
}
public static void main(String [] args){ MySwingTest mst = new MySwingTest(); }class NewPanel extends JPanel {
public NewPanel() {
}
public void paintComponent(Graphics g) { int x = 0, y = 0; ImageIcon icon = new ImageIcon(image); g.drawImage(icon.getImage(), x, y, getSize().width,getSize().height, this); while (true) { g.drawImage(icon.getImage(), x, y, this); if (x > getSize().width && y > getSize().height) break; // 这段代码是为了保证在窗口大于图片时，图片仍能覆盖整个窗口 if (x > getSize().width) { x = 0; y += icon.getIconHeight(); } else x += icon.getIconWidth(); } g.drawString("abcdefg", 200, 200);//在图片的特定位置加上文字 } }}3.文字旋转显示
public class Rotate {
public static void main(String[] args) {
JFrame jf = new JFrame(); jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); jf.getContentPane().add(new RotatePanel()); jf.setPreferredSize(new Dimension(500, 400)); jf.pack(); jf.setVisible(true);}
}
class RotatePanel extends JPanel {
protected void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2d = (Graphics2D) g;g2d.setColor(Color.WHITE);
g2d.fillRect(0, 0, this.getWidth(), this.getHeight());String s = "Java 2d 旋转";
Font f = new Font("宋体", Font.BOLD, 16); Color[] colors = { Color.ORANGE, Color.LIGHT_GRAY }; g2d.setFont(f);// 平移原点到图形环境的中心
g2d.translate(this.getWidth() / 2, this.getHeight() / 2);// 旋转文本
for (int i = 0; i < 12; i++) { g2d.rotate(30 * Math.PI / 180); g2d.setPaint(colors[i % 2]); g2d.drawString(s, 0, 0); } }}4.BufferedImage处理图像
BufferedImage是Image的一个子类，BufferedImage生成的图片在内存里有一个图像缓冲区，利用这个缓冲区我们可以很方便的操作这个图片，通常用来做图片修改操作如大小变换、图片变灰、设置图片透明或不透明等。
BufferedImage bufferedImage = ImageIO.read(new FileInputStream(filePath));
public BufferedImage getGrayPicture(BufferedImage originalImage)
{ int green=0,red=0,blue=0,rgb; int imageWidth = originalImage.getWidth(); int imageHeight = originalImage.getHeight(); for(int i = originalImage.getMinX();i < imageWidth ;i++){ for(int j = originalImage.getMinY();j < imageHeight ;j++){ //图片的像素点其实是个矩阵，这里利用两个for循环来对每个像素进行操作 Object data = routeImage.getRaster().getDataElements(i, j, null);//获取该点像素，并以object类型表示 red = routeImage.getColorModel().getRed(data); blue = routeImage.getColorModel().getBlue(data); green = routeImage.getColorModel().getGreen(data); red = (red*3 + green*6 + blue*1)/10; green = red; blue = green; /* 这里将r、g、b再转化为rgb值，因为bufferedImage没有提供设置单个颜色的方法，只能设置rgb。rgb最大为8388608，当大于这个值时，应减去 255*255*25516777216 */ rgb = (red*256 + green)*256+blue; if(rgb>8388608){ rgb = rgb - 16777216; } //将rgb值写回图片 routeImage.setRGB(i, j, rgb); } } return originalImage; }