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似乎无法修复代码中的Graphics2D缺乏，那么我必须为动画设置修复大小，否则一些开始外面Rectangle 490 x 490冻结或在屏幕上晃动
我的SSCCE
import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.image.BufferedImage; import java.util.ArrayList; import java.util.Random; import java.util.Vector; import java.util.regex.Pattern; import javax.swing.*; import javax.swing.table.*; public class OneTwoThree implements Runnable { private String testS; private JFrame frame = new JFrame("frameTitle"); private JScrollPane tblS = new JScrollPane(); private JTable tbl; private Vector<String> rOrH; private long t1 = 0L; private long t2 = 0L; private AlphaChars aChars = new AlphaChars(); private GradientViewPortOriginal tableViewPort; private JViewport viewport = new JViewport(); private Random random = new Random(); private Vector<Vector<Integer>> vec = new Vector<Vector<Integer>>(); private boolean bolo = false; public OneTwoThree() { t1 = System.currentTimeMillis(); int regLenght = 3500; int chars = 0; testS = aChars.getNext(regLenght); rOrH = new Vector<String>(); Vector<Vector<String>> rowD = new Vector<Vector<String>>(); for (int e = 0; e < regLenght;) { chars++; if (chars > 50) { chars = 1; rowD.add(rOrH); rOrH = new Vector<String>(); } String str = (testS.substring(e, (e + 1))).toString(); if (str != null) { rOrH.add(str); } else { rOrH.add(""); } e++; } rOrH = new Vector<String>(); for (int i = 0; i < 50; i++) { rOrH.add(String.valueOf(i + 1)); } tbl = new JTable(rowD, rOrH); TableColumnModel tcm = tbl.getColumnModel(); for (int i = 0; i < (tcm.getColumnCount()); i++) { tcm.getColumn(i).setPreferredWidth(4); } tbl.setGridColor(tbl.getBackground()); tbl.setRowHeight(10); tbl.setTableHeader(null); tbl.setPreferredScrollableViewportSize(tbl.getPreferredSize()); tbl.setRowSelectionAllowed(false); tbl.setColumnSelectionAllowed(false); tableViewPort = new GradientViewPortOriginal(tbl); viewport = tableViewPort.getViewport(); RepaintManager.setCurrentManager(new RepaintManager() { @Override public void addDirtyRegion(JComponent c, int x, int y, int w, int h) { Container con = c.getParent(); while (con instanceof JComponent) { if (!con.isVisible()) { return; } if (con instanceof GradientViewPortOriginal) { c = (JComponent) con; x = 0; y = 0; w = con.getWidth(); h = con.getHeight(); } con = con.getParent(); } super.addDirtyRegion(c, x, y, w, h); } }); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.add(tableViewPort, BorderLayout.CENTER); frame.setLocation(20, 20); frame.pack(); frame.setVisible(true); addColumnRenderes(); for (int i = 0; i < 35; i++) { Star star = new Star(new Point(random.nextInt(490), random.nextInt(490))); star.setColor(new Color(100 + random.nextInt(155), 100 + random.nextInt(155), 100 + random.nextInt(155))); star.setxIncr(-3 + random.nextInt(7)); star.setyIncr(-3 + random.nextInt(7)); tableViewPort.add(star); } } private void addColumnRenderes() { for (int i = 0; i < tbl.getColumnCount(); i++) { RowColorRenderer rowRenderer = new RowColorRenderer(i); TableColumn column = tbl.getColumnModel().getColumn(i); column.setCellRenderer(rowRenderer); } addTableData(); } private void addTableData() { tbl.setValueAt("8", 4, 25);tbl.setValueAt("4", 5, 24);tbl.setValueAt("1", 5, 25);tbl.setValueAt("4", 5, 26); tbl.setValueAt("4", 6, 23);tbl.setValueAt("4", 6, 25);tbl.setValueAt("1", 6, 26);tbl.setValueAt("4", 6, 27); tbl.setValueAt("1", 6, 28);tbl.setValueAt("1", 7, 21);tbl.setValueAt("4", 7, 22);tbl.setValueAt("1", 7, 23); tbl.setValueAt("4", 7, 24);tbl.setValueAt("1", 7, 27);tbl.setValueAt("8", 7, 28);tbl.setValueAt("4", 8, 23); tbl.setValueAt("1", 8, 24);tbl.setValueAt("1", 8, 25);tbl.setValueAt("8", 8, 26);tbl.setValueAt("8", 8, 27); tbl.setValueAt("7", 9, 24);tbl.setValueAt("1", 9, 26);tbl.setValueAt("4", 9, 25);tbl.setValueAt("4", 10, 24); tbl.setValueAt("1", 10, 25);tbl.setValueAt("8", 10, 26);tbl.setValueAt("4", 11, 23);tbl.setValueAt("4", 11, 27); tbl.setValueAt("1", 12, 21);tbl.setValueAt("4", 12, 22);tbl.setValueAt("8", 12, 28);tbl.setValueAt("4", 13, 21); tbl.setValueAt("8", 13, 29);tbl.setValueAt("1", 14, 19);tbl.setValueAt("4", 14, 20);tbl.setValueAt("8", 14, 30); tbl.setValueAt("4", 15, 19);tbl.setValueAt("4", 15, 20);tbl.setValueAt("4", 15, 21);tbl.setValueAt("1", 15, 22); tbl.setValueAt("4", 15, 23);tbl.setValueAt("1", 15, 31);tbl.setValueAt("1", 15, 32);tbl.setValueAt("4", 16, 22); tbl.setValueAt("4", 17, 21);tbl.setValueAt("4", 18, 20);tbl.setValueAt("4", 19, 20);tbl.setValueAt("4", 20, 19); tbl.setValueAt("4", 21, 17);tbl.setValueAt("4", 21, 18);tbl.setValueAt("4", 22, 16);tbl.setValueAt("4", 22, 17); tbl.setValueAt("4", 22, 18);tbl.setValueAt("4", 22, 19);tbl.setValueAt("4", 22, 20);tbl.setValueAt("4", 24, 18); tbl.setValueAt("4", 25, 17);tbl.setValueAt("4", 25, 17);tbl.setValueAt("4", 26, 16);tbl.setValueAt("4", 27, 15); tbl.setValueAt("4", 27, 16);tbl.setValueAt("4", 27, 18);tbl.setValueAt("4", 28, 17);tbl.setValueAt("4", 29, 16); tbl.setValueAt("4", 30, 15);tbl.setValueAt("4", 31, 14);tbl.setValueAt("4", 32, 13);tbl.setValueAt("4", 33, 12); tbl.setValueAt("4", 33, 13);tbl.setValueAt("4", 33, 14);tbl.setValueAt("4", 33, 18);tbl.setValueAt("4", 34, 17); tbl.setValueAt("4", 35, 16);tbl.setValueAt("4", 36, 15);tbl.setValueAt("4", 37, 14);tbl.setValueAt("4", 38, 13); tbl.setValueAt("4", 39, 12);tbl.setValueAt("4", 40, 11);tbl.setValueAt("4", 41, 10);tbl.setValueAt("4", 42, 9); tbl.setValueAt("4", 42, 10);tbl.setValueAt("4", 42, 11);tbl.setValueAt("4", 38, 18);tbl.setValueAt("4", 39, 18); tbl.setValueAt("4", 40, 18);tbl.setValueAt("4", 41, 17);tbl.setValueAt("4", 42, 16);tbl.setValueAt("4", 43, 15); tbl.setValueAt("4", 44, 14);tbl.setValueAt("4", 46, 13);tbl.setValueAt("4", 47, 12);tbl.setValueAt("4", 48, 11); tbl.setValueAt("4", 49, 10);tbl.setValueAt("4", 50, 9);tbl.setValueAt("4", 51, 8);tbl.setValueAt("4", 52, 7); tbl.setValueAt("4", 53, 6);tbl.setValueAt("4", 54, 5);tbl.setValueAt("4", 55, 4);tbl.setValueAt("4", 56, 6); tbl.setValueAt("4", 56, 8);tbl.setValueAt("4", 56, 9);tbl.setValueAt("4", 56, 10);tbl.setValueAt("4", 56, 12); tbl.setValueAt("4", 56, 13);tbl.setValueAt("4", 58, 10);tbl.setValueAt("4", 59, 11);tbl.setValueAt("4", 59, 12); tbl.setValueAt("4", 60, 13);tbl.setValueAt("4", 61, 15);tbl.setValueAt("4", 61, 16);tbl.setValueAt("4", 59, 17); tbl.setValueAt("4", 58, 18);tbl.setValueAt("4", 57, 19);tbl.setValueAt("4", 62, 18);tbl.setValueAt("4", 63, 19); tbl.setValueAt("4", 63, 20);tbl.setValueAt("3", 62, 23);tbl.setValueAt("3", 63, 23);tbl.setValueAt("3", 64, 23); tbl.setValueAt("3", 65, 23);tbl.setValueAt("3", 66, 23);tbl.setValueAt("3", 67, 23);tbl.setValueAt("3", 62, 28); tbl.setValueAt("3", 63, 28);tbl.setValueAt("3", 64, 28);tbl.setValueAt("3", 65, 28);tbl.setValueAt("3", 66, 28); tbl.setValueAt("3", 67, 28);tbl.setValueAt("8", 14, 26);tbl.setValueAt("8", 14, 27);tbl.setValueAt("8", 16, 27); tbl.setValueAt("8", 16, 28);tbl.setValueAt("8", 17, 29);tbl.setValueAt("8", 18, 30);tbl.setValueAt("8", 19, 31); tbl.setValueAt("8", 20, 32);tbl.setValueAt("8", 21, 31);tbl.setValueAt("8", 22, 30);tbl.setValueAt("8", 22, 29); tbl.setValueAt("3", 20, 27);tbl.setValueAt("3", 21, 26);tbl.setValueAt("3", 22, 25);tbl.setValueAt("3", 23, 24); tbl.setValueAt("3", 24, 24);tbl.setValueAt("3", 24, 25);tbl.setValueAt("3", 24, 26);tbl.setValueAt("8", 22, 32); tbl.setValueAt("8", 23, 33);tbl.setValueAt("8", 24, 34);tbl.setValueAt("8", 25, 35);tbl.setValueAt("8", 26, 36); tbl.setValueAt("8", 27, 37);tbl.setValueAt("8", 29, 34);tbl.setValueAt("8", 29, 35);tbl.setValueAt("8", 28, 36); tbl.setValueAt("8", 30, 32);tbl.setValueAt("8", 31, 33);tbl.setValueAt("8", 32, 34);tbl.setValueAt("8", 33, 35); tbl.setValueAt("8", 34, 36);tbl.setValueAt("8", 34, 37);tbl.setValueAt("3", 27, 30);tbl.setValueAt("3", 28, 29); tbl.setValueAt("3", 29, 28);tbl.setValueAt("3", 30, 28);tbl.setValueAt("3", 31, 29);tbl.setValueAt("3", 32, 30); tbl.setValueAt("3", 31, 24);tbl.setValueAt("3", 32, 23);tbl.setValueAt("3", 33, 22);tbl.setValueAt("3", 34, 22); tbl.setValueAt("3", 34, 23);tbl.setValueAt("3", 34, 24);tbl.setValueAt("3", 37, 20);tbl.setValueAt("3", 38, 19); tbl.setValueAt("3", 39, 18);tbl.setValueAt("3", 40, 18);tbl.setValueAt("3", 41, 19);tbl.setValueAt("3", 42, 20); tbl.setValueAt("3", 36, 34);tbl.setValueAt("3", 37, 33);tbl.setValueAt("3", 38, 32);tbl.setValueAt("3", 39, 32); tbl.setValueAt("3", 39, 33);tbl.setValueAt("3", 39, 34);tbl.setValueAt("3", 40, 24);tbl.setValueAt("3", 41, 23); tbl.setValueAt("3", 42, 22);tbl.setValueAt("3", 43, 22);tbl.setValueAt("3", 43, 23);tbl.setValueAt("3", 43, 24); tbl.setValueAt("3", 42, 30);tbl.setValueAt("3", 43, 29);tbl.setValueAt("3", 44, 28);tbl.setValueAt("3", 45, 28); tbl.setValueAt("3", 46, 29);tbl.setValueAt("3", 47, 30);tbl.setValueAt("3", 50, 21);tbl.setValueAt("3", 51, 20); tbl.setValueAt("3", 52, 19);tbl.setValueAt("3", 53, 19);tbl.setValueAt("3", 53, 20);tbl.setValueAt("3", 53, 21); tbl.setValueAt("3", 50, 31);tbl.setValueAt("3", 51, 30);tbl.setValueAt("3", 52, 29);tbl.setValueAt("3", 53, 29); tbl.setValueAt("3", 53, 30);tbl.setValueAt("3", 53, 31);tbl.setValueAt("3", 47, 15);tbl.setValueAt("3", 48, 14); tbl.setValueAt("3", 49, 13);tbl.setValueAt("3", 50, 13);tbl.setValueAt("3", 51, 14);tbl.setValueAt("3", 52, 15); tbl.setValueAt("3", 51, 25);tbl.setValueAt("3", 52, 24);tbl.setValueAt("3", 53, 23);tbl.setValueAt("3", 54, 23); tbl.setValueAt("3", 55, 24);tbl.setValueAt("3", 46, 25);tbl.setValueAt("3", 50, 38);tbl.setValueAt("3", 51, 37); tbl.setValueAt("3", 52, 36);tbl.setValueAt("3", 53, 36);tbl.setValueAt("3", 54, 37);tbl.setValueAt("3", 55, 38); tbl.setValueAt("3", 58, 28);tbl.setValueAt("3", 59, 27);tbl.setValueAt("3", 60, 26);tbl.setValueAt("3", 58, 26); tbl.setValueAt("3", 59, 27);tbl.setValueAt("3", 60, 28);tbl.setValueAt("8", 37, 36);tbl.setValueAt("8", 38, 37); tbl.setValueAt("8", 38, 38);tbl.setValueAt("8", 40, 39);tbl.setValueAt("8", 41, 40);tbl.setValueAt("8", 42, 41); tbl.setValueAt("8", 43, 41);tbl.setValueAt("8", 44, 38);tbl.setValueAt("8", 44, 39);tbl.setValueAt("8", 44, 40); tbl.setValueAt("8", 43, 35);tbl.setValueAt("8", 44, 36);tbl.setValueAt("8", 45, 37);tbl.setValueAt("8", 46, 38); tbl.setValueAt("8", 47, 39);tbl.setValueAt("8", 48, 40);tbl.setValueAt("8", 49, 41);tbl.setValueAt("8", 50, 42); tbl.setValueAt("8", 51, 43);tbl.setValueAt("8", 52, 44);tbl.setValueAt("8", 53, 45);tbl.setValueAt("8", 54, 43); tbl.setValueAt("8", 55, 42);tbl.setValueAt("8", 56, 41);tbl.setValueAt("8", 59, 31);tbl.setValueAt("8", 60, 32); tbl.setValueAt("8", 61, 33);tbl.setValueAt("8", 62, 34);tbl.setValueAt("8", 58, 36);tbl.setValueAt("8", 59, 37); tbl.setValueAt("8", 60, 38);tbl.setValueAt("8", 61, 39);tbl.setValueAt("8", 62, 40);tbl.setValueAt("8", 62, 41); tbl.setValueAt("8", 60, 35);tbl.setValueAt("8", 61, 36);tbl.setValueAt("8", 62, 37);tbl.setValueAt("8", 58, 45); tbl.setValueAt("8", 59, 42);tbl.setValueAt("8", 59, 43);tbl.setValueAt("8", 59, 44);tbl.setValueAt("8", 62, 40); frame.setTitle(" - - > Merry Christmast < - - "); t2 = System.currentTimeMillis(); System.out.println("miliSec:" + (t2 - t1)); //aver. 32 miliSec. new Thread(this).start(); } @Override public void run() { while (true) { try { Thread.sleep(1000); } catch (Exception e) { e.printStackTrace(); } if (!bolo) { for (int i = 0; i < 30; i++) { Vector<Integer> vecLocal = new Vector<Integer>(); final int r1 = random.nextInt(tbl.getRowCount() - 1); final int c1 = random.nextInt(tbl.getColumnCount() - 1); vecLocal.add(r1); vecLocal.add(c1); vec.add(vecLocal); addSnowFlag(); try { Thread.sleep(250); } catch (Exception e) { e.printStackTrace(); } } bolo = true; } else { Vector<Integer> vecLocal = new Vector<Integer>(); final int r = random.nextInt(tbl.getRowCount() - 1); final int c = random.nextInt(tbl.getColumnCount() - 1); vecLocal.add(r); vecLocal.add(c); vec.add(vecLocal); addSnowFlag(); try { Thread.sleep(500); } catch (Exception e) { e.printStackTrace(); } } } } private void addSnowFlag() { if (vec.size() > -1) { Vector<Integer> vecLocal = vec.elementAt(vec.size() - 1); final int r = vecLocal.elementAt(0); final int c = vecLocal.elementAt(1); String str = String.valueOf(tbl.getValueAt(r, c)); if (!str.isEmpty()) { if (!Pattern.compile("\\d").matcher(str).find()) { if (!Pattern.compile("[123456789]").matcher(str).find()) { Runnable doRun = new Runnable() { @Override public void run() { tbl.setValueAt("9", r, c); } }; SwingUtilities.invokeLater(doRun); if (bolo) { Vector<Integer> vecLocal1 = vec.elementAt(0); final int r1 = vecLocal1.elementAt(0); final int c1 = vecLocal1.elementAt(1); Runnable doRun1 = new Runnable() { @Override public void run() { tbl.setValueAt(aChars.getNext(1), r1, c1); vec.removeElementAt(0); } }; SwingUtilities.invokeLater(doRun1); } } } } } } private class GradientViewPortOriginal extends JScrollPane { private static final long serialVersionUID = 1L; private final int h = 80; private BufferedImage img = null; private BufferedImage shadow = new BufferedImage(1, h, BufferedImage.TYPE_INT_ARGB); private JViewport viewPort; private ArrayList<Star> stars = new ArrayList<Star>(); public GradientViewPortOriginal(JComponent com) { super(com); viewPort = this.getViewport(); viewPort.setScrollMode(JViewport.BLIT_SCROLL_MODE); viewPort.setScrollMode(JViewport.BACKINGSTORE_SCROLL_MODE); viewPort.setScrollMode(JViewport.SIMPLE_SCROLL_MODE); setPreferredSize(this.getPreferredSize()); paintBackGround(new Color(250, 250, 150)); } public void add(Star star) { stars.add(star); } // private Timer timer = new Timer(33, new ActionListener() { @Override public void actionPerformed(ActionEvent e) { for (Star star : stars) { star.move(); } repaint(); } }); public void startAnimation() { if (!timer.isRunning()) { timer.start(); } } @Override public void addNotify() { super.addNotify(); timer.start(); } private void paintBackGround(Color g) { Graphics2D g2 = shadow.createGraphics(); g2.setPaint(g); g2.fillRect(0, 0, 1, h); g2.setComposite(AlphaComposite.DstIn); g2.setPaint(new GradientPaint(0, 0, new Color(0, 0, 0, 0f), 0, h, new Color(0.8f, 0.8f, 0.8f, 0.5f))); g2.fillRect(0, 0, 1, h); g2.dispose(); } @Override public void paint(Graphics g) { if (img == null || img.getWidth() != getWidth() || img.getHeight() != getHeight()) { img = new BufferedImage(getWidth(), getHeight(), BufferedImage.TYPE_INT_ARGB); } Graphics2D g2 = img.createGraphics(); super.paint(g2); ((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); Rectangle bounds = getViewport().getVisibleRect(); g2.scale(bounds.getWidth(), -1); int y = (getColumnHeader() == null) ? 0 : getColumnHeader().getHeight(); g2.drawImage(shadow, bounds.x, -bounds.y - y - h, null); g2.scale(1, -1); g2.drawImage(shadow, bounds.x, bounds.y + bounds.height - h + y, null); g2.dispose(); g.drawImage(img, 0, 0, null); for (Star star : stars) { g.setColor(star.getColor()); g.fillPolygon(star); } } } private class RowColorRenderer extends DefaultTableCellRenderer { private static final long serialVersionUID = 1L; private int colNo = 0; RowColorRenderer(int col) { colNo = col; } @Override public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) { Component comp = super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column); if (!isSelected) { if (table.getValueAt(row, colNo) != null) { String str = table.getValueAt(row, colNo).toString(); if (!str.isEmpty()) { if (Pattern.compile("\\d").matcher(str).find()) { if (((Pattern.compile("[9]").matcher(str).find()))) { setBackground(new Color(250, 250, 150)); setForeground(new Color(250, 250, 150)); setFont(new Font("Serif", Font.BOLD, 9)); } else if (((Pattern.compile("[1]").matcher(str).find()))) { setBackground(tbl.getBackground()); setForeground(Color.orange); setFont(new Font("Serif", Font.BOLD, 8)); } else { setBackground(tbl.getBackground()); setForeground(Color.gray); setFont(new Font("Serif", Font.BOLD, 9)); } } else { setBackground(tbl.getBackground()); setForeground(Color.lightGray); setFont(new Font("Serif", Font.PLAIN, 6)); } } } } setHorizontalAlignment(CENTER); return this; } } private class AlphaChars { public static final int MIN_LENGTH = 2000; private java.util.Random rand = new java.util.Random(); private char[] AlphaChars = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',}; /*'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '+', '-', '*', '/', '<', '>', '&', '#', '@', '{', '}', '?', ':', '_', '"', '!', ')', '('};*/ public String getNext() { StringBuilder strbuf = new StringBuilder(); for (int i = 0; i < MIN_LENGTH; i++) { strbuf.append(getAlphaChars()[getRand().nextInt(getAlphaChars().length)]); } return strbuf.toString(); } public String getNext(int reqLenght) { StringBuilder strbuf = new StringBuilder(); for (int i = 0; i < reqLenght; i++) { strbuf.append(getAlphaChars()[getRand().nextInt(getAlphaChars().length)]); } return strbuf.toString(); } public java.util.Random getRand() { return rand; } public void setRand(java.util.Random aRand) { rand = aRand; } public char[] getAlphaChars() { return AlphaChars; } public void setAlphaChars(char[] aAlphaChars) { AlphaChars = aAlphaChars; } } private class Star extends Polygon { private static final long serialVersionUID = 1L; private Point location = null; private Color color = Color.YELLOW; private int xIncr, yIncr; static final int WIDTH = 500, HEIGHT = 500; Star(Point location) { int x = location.x; int y = location.y; this.location = location; this.addPoint(x, y + 8); this.addPoint(x + 8, y + 8); this.addPoint(x + 11, y); this.addPoint(x + 14, y + 8); this.addPoint(x + 22, y + 8); this.addPoint(x + 17, y + 12); this.addPoint(x + 21, y + 20); this.addPoint(x + 11, y + 14); this.addPoint(x + 3, y + 20); this.addPoint(x + 6, y + 12); } public void setColor(Color color) { this.color = color; } public void move() { if (location.x < 0 || location.x > WIDTH) { xIncr = -xIncr; } if (location.y < 0 || location.y > WIDTH) { yIncr = -yIncr; } translate(xIncr, yIncr); location.setLocation(location.x + xIncr, location.y + yIncr); } public void setxIncr(int xIncr) { this.xIncr = xIncr; } public void setyIncr(int yIncr) { this.yIncr = yIncr; } public Color getColor() { return color; } } public static void main(String args[]) { Runnable doRun = new Runnable() { @Override public void run() { OneTwoThree hnvit = new OneTwoThree(); } }; SwingUtilities.invokeLater(doRun); } } 我希望所有的Java贡献者Merry Merrymast在这里
编辑：
请change private class Star extends Polygon {方法move()到—>
public void move() { if (location.x < 0 || location.x > frame.getContentPane().getWidth() - 20) { xIncr = -xIncr; } if (location.y < 0 || location.y > frame.getContentPane().getHeight() - 20) { yIncr = -yIncr; } translate(xIncr, yIncr); location.setLocation(location.x + xIncr, location.y + yIncr); }
下面的例子为你的树创建MAX饰品。 它使用ComponentListener来重新定位任何外面的装饰物。
package merrychristmas; import java.awt.AlphaComposite; import java.awt.Color; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.ComponentAdapter; import java.awt.event.ComponentEvent; import java.util.LinkedList; import java.util.Queue; import java.util.Random; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.Timer; public class Baubles extends JPanel implements ActionListener { private static final int MAX = 64; private static final String TITLE = "Baubles"; private static final Random rnd = new Random(); private static final AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.75f); private final Timer timer = new Timer(100, this); private final Queue<Bauble> queue = new LinkedList<Bauble>(); public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { JFrame f = new JFrame(TITLE); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); Baubles dt = new Baubles(); f.add(dt); f.pack(); f.setLocationRelativeTo(null); f.setVisible(true); } }); } public Baubles() { this.setPreferredSize(new Dimension(8 * MAX, 8 * MAX)); this.addComponentListener(new ComponentAdapter() { @Override // relocate any outliers public void componentResized(ComponentEvent e) { for (Bauble bauble : queue) { if (bauble.x > getWidth() || bauble.y > getHeight()) { bauble.x = rnd.nextInt(getWidth()); bauble.y = rnd.nextInt(getHeight()); } } } }); timer.start(); } @Override public void actionPerformed(ActionEvent e) { if (queue.isEmpty()) { for (int i = 0; i < MAX; i++) { queue.add(randomBauble()); } } queue.add(randomBauble()); queue.remove(); this.repaint(); } @Override public void paintComponent(Graphics g) { Graphics2D g2d = (Graphics2D) g; g2d.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2d.setColor(Color.black); g2d.fillRect(0, 0, getWidth(), this.getHeight()); g2d.setComposite(ac); for (Bauble b : queue) { g2d.setColor(bc); g2d.fillOval(bx, by, bd, bd); } } private Bauble randomBauble() { int x = rnd.nextInt(getWidth()); int y = rnd.nextInt(getHeight()); int r = rnd.nextInt(MAX) + MAX / 2; Color c = new Color(rnd.nextInt()); return new Bauble(x, y, r, c); } private static class Bauble { private int x, y, d; private Color c; public Bauble(int x, int y, int r, Color c) { this.x = x - r; this.y = y - r; this.d = 2 * r; this.c = c; } } }
