带图标和缩略图的列表框JList，缩略图列表框jlist,带图标和缩略图的列表框J
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带图标和缩略图的列表框JList，缩略图列表框jlist,带图标和缩略图的列表框J
带图标和缩略图的列表框JList
public class PolymorphicJList extends JList { static Color listForeground, listBackground, listSelectionForeground, listSelectionBackground; static { UIDefaults uid = UIManager.getLookAndFeel().getDefaults(); listForeground = uid.getColor ("List.foreground"); listBackground = uid.getColor ("List.background"); listSelectionForeground = uid.getColor ("List.selectionForeground"); listSelectionBackground = uid.getColor ("List.selectionBackground"); }ImageIcon fileIcon, textFileIcon, directoryIcon, imageFileIcon, pngFileIcon, gifFileIcon, jpegFileIcon; JComponent fileCellPrototype, textCellPrototype, imageCellPrototype, directoryCellPrototype; JLabel fileNameLabel, textNameLabel, directoryNameLabel, imageNameLabel, fileSizeLabel, textSizeLabel, textWordCountLabel, directoryCountLabel, imageSizeLabel, imageIconLabel; public PolymorphicJList (File dir) { super(); buildPrototypeCells(); setCellRenderer (new PolyRenderer()); setModel (new DefaultListModel()); if (! dir.isDirectory()) dir = new File (dir.getParent()); buildModelFromDir (dir); } public static void main (String[] args) { File dir = new File ("."); if (args.length > 0) dir = new File (args[0]); JList list = new PolymorphicJList (dir); JScrollPane pain = new JScrollPane (list, ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER); JFrame frame = new JFrame ("PolymorphicJList"); frame.getContentPane().add (pain); frame.pack(); frame.setVisible(true); } protected void buildModelFromDir (File dir) { File[] files = dir.listFiles(); DefaultListModel mod = (DefaultListModel) getModel(); for (int i=0; i<files.length; i++) { if (isTextFile (files[i])) mod.addElement (new TextFileItem (files[i])); else if (isImageFile (files [i])) mod.addElement (new ImageFileItem (files[i])); else if (files[i].isDirectory()) mod.addElement (new DirectoryItem (files[i]));else mod.addElement (new FileItem (files[i])); } } protected boolean isImageFile(File f) { if (f.isDirectory()) return false; String name = f.getName(); return name.endsWith (".gif") || name.endsWith (".GIF") || name.endsWith (".jpg") || name.endsWith (".JPG") || name.endsWith (".jpeg") || name.endsWith (".JPEG") || name.endsWith (".bmp") || name.endsWith (".BMP") || name.endsWith (".png") || name.endsWith (".PNG"); } protected boolean isTextFile(File f) { if (f.isDirectory()) return false; String name = f.getName(); return name.endsWith (".txt") || name.endsWith (".html") || name.endsWith (".xml") || name.endsWith (".xhtml") || name.endsWith (".java") || name.endsWith (".c") || name.endsWith (".cpp") || name.endsWith (".c++") || name.endsWith (".m") || name.endsWith (".h"); } protected void buildIcons() { String SEP = System.getProperty ("file.separator"); fileIcon = new ImageIcon ("images" + SEP + "generic.gif"); textFileIcon = new ImageIcon ("images" + SEP + "text.gif"); directoryIcon = new ImageIcon ("images" + SEP + "folder.gif"); imageFileIcon = new ImageIcon ("images" + SEP + "image.gif"); pngFileIcon = new ImageIcon ("images" + SEP + "png.gif"); gifFileIcon = new ImageIcon ("images" + SEP + "gif.gif"); jpegFileIcon = new ImageIcon ("images" + SEP + "jpeg.gif"); } protected void buildPrototypeCells() { buildIcons(); fileCellPrototype = new JPanel(); fileCellPrototype.setLayout (new GridBagLayout()); addWithGridBag (new JLabel(fileIcon), fileCellPrototype, 0, 0, 1, 2, GridBagConstraints.WEST, GridBagConstraints.BOTH, 0, 0); fileNameLabel = new JLabel(); Font defaultLabelFont = fileNameLabel.getFont(); Font nameFont = defaultLabelFont.deriveFont (Font.BOLD, defaultLabelFont.getSize()+2); fileNameLabel.setFont (nameFont); addWithGridBag (fileNameLabel, fileCellPrototype, 1, 0, 1, 1, GridBagConstraints.NORTH, GridBagConstraints.HORIZONTAL, 1, 0); fileSizeLabel = new JLabel(); addWithGridBag (fileSizeLabel, fileCellPrototype, 1, 1, 1, 1, GridBagConstraints.SOUTH, GridBagConstraints.HORIZONTAL, 1, 0); opacify (fileCellPrototype); // text file textCellPrototype = new JPanel(); textCellPrototype.setLayout (new GridBagLayout()); addWithGridBag (new JLabel(textFileIcon), textCellPrototype, 0, 0, 1, 2, GridBagConstraints.WEST, GridBagConstraints.BOTH, 0, 0); textNameLabel = new JLabel(); textNameLabel.setFont (nameFont); addWithGridBag (textNameLabel, textCellPrototype, 1, 0, 2, 1, GridBagConstraints.NORTH, GridBagConstraints.HORIZONTAL, 1, 0); textSizeLabel = new JLabel(); textWordCountLabel = new JLabel(); addWithGridBag (textSizeLabel, textCellPrototype, 1, 1, 1, 1, GridBagConstraints.NORTH, GridBagConstraints.HORIZONTAL, 0, 0); addWithGridBag (textWordCountLabel, textCellPrototype, 2, 1, 1, 1, GridBagConstraints.SOUTH, GridBagConstraints.HORIZONTAL, 1, 0); opacify (textCellPrototype); // directory directoryCellPrototype = new JPanel(); directoryCellPrototype.setLayout (new GridBagLayout()); addWithGridBag (new JLabel(directoryIcon), directoryCellPrototype, 0, 0, 1, 2, GridBagConstraints.WEST, GridBagConstraints.BOTH, 0, 0); directoryNameLabel = new JLabel(); directoryNameLabel.setFont (nameFont); addWithGridBag (directoryNameLabel, directoryCellPrototype, 1, 0, 1, 1, GridBagConstraints.NORTH, GridBagConstraints.HORIZONTAL, 1, 0); directoryCountLabel = new JLabel(); addWithGridBag (directoryCountLabel, directoryCellPrototype, 1, 1, 1, 1, GridBagConstraints.SOUTH, GridBagConstraints.HORIZONTAL, 1, 0); opacify (directoryCellPrototype); // image imageCellPrototype = new JPanel(); imageCellPrototype.setLayout (new GridBagLayout()); addWithGridBag (new JLabel(imageFileIcon), imageCellPrototype, 0, 0, 1, 2, GridBagConstraints.WEST, GridBagConstraints.BOTH, 0, 0); imageNameLabel = new JLabel(); imageNameLabel.setFont (nameFont); addWithGridBag (imageNameLabel, imageCellPrototype, 1, 0, 1, 1, GridBagConstraints.NORTH, GridBagConstraints.HORIZONTAL, 1, 0); imageSizeLabel = new JLabel(); addWithGridBag (imageSizeLabel, imageCellPrototype, 1, 1, 1, 1, GridBagConstraints.SOUTH, GridBagConstraints.HORIZONTAL, 1, 0); imageIconLabel = new JLabel(); addWithGridBag (imageIconLabel, imageCellPrototype, 2, 0, 1, 2, GridBagConstraints.EAST, GridBagConstraints.VERTICAL, 0, 0); opacify (imageCellPrototype);}private void addWithGridBag (Component comp, Container cont, int x, int y, int width, int height, int anchor, int fill, int weightx, int weighty) { GridBagConstraints gbc = new GridBagConstraints(); gbc.gridx = x; gbc.gridy = y; gbc.gridwidth = width; gbc.gridheight = height; gbc.anchor = anchor; gbc.fill = fill; gbc.weightx = weightx; gbc.weighty = weighty; cont.add (comp, gbc); } private void opacify (Container prototype) { Component[] comps = prototype.getComponents(); for (int i=0; i<comps.length; i++) { if (comps[i] instanceof JComponent) ((JComponent)comps[i]).setOpaque(true); } }class FileItem extends Object { File file; public FileItem (File f) { file = f; } }class ImageFileItem extends FileItem { ImageIcon icon; public ImageFileItem (File f) { super(f); initIcon(); } void initIcon() { icon = new ImageIcon (file.getPath()); // scale to 32 pix in largest dimension Image img = icon.getImage(); float factor = 1.0f; if (img.getWidth(null) > img.getHeight(null)) factor = Math.min (32f / img.getWidth(null), 1.0f); else factor = Math.min (32f / img.getHeight(null), 1.0f); Image scaledImage = img.getScaledInstance ((int) (img.getWidth(null) * factor), (int) (img.getHeight(null) * factor), Image.SCALE_FAST); icon.setImage(scaledImage); } }class DirectoryItem extends FileItem { int childCount; public DirectoryItem (File f) { super(f); initChildCount(); } public int getChildCount() { return childCount; } void initChildCount () { if (! file.isDirectory()) childCount = -1; else childCount = file.listFiles().length; System.out.println (file.getPath() + ": " + childCount + " items"); } }class TextFileItem extends FileItem { int wordCount = -1; public TextFileItem (File f) { super(f); initWordCount(); } public int getWordCount() { return wordCount; } protected void initWordCount() { try { StreamTokenizer izer = new StreamTokenizer (new BufferedReader (new FileReader(file))); while (izer.nextToken() != StreamTokenizer.TT_EOF) wordCount++; } catch (Exception e) { e.printStackTrace(); wordCount = -1; } System.out.println (file.getPath() + ": " + wordCount + " words"); } }class PolyRenderer extends Object implements ListCellRenderer { public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) { if (value instanceof DirectoryItem) { DirectoryItem item = (DirectoryItem) value; directoryNameLabel.setText (item.file.getName()); directoryCountLabel.setText (item.getChildCount() + " items"); setColorsForSelectionState (directoryCellPrototype, isSelected); return directoryCellPrototype; } else if (value instanceof TextFileItem) { TextFileItem item = (TextFileItem) value; // populate values textNameLabel.setText (item.file.getName()); textSizeLabel.setText (item.file.length() + " bytes "); textWordCountLabel.setText (item.getWordCount() + " words"); setColorsForSelectionState (textCellPrototype, isSelected); return textCellPrototype; } else if (value instanceof ImageFileItem) { ImageFileItem item = (ImageFileItem) value; // pouplate values imageNameLabel.setText (item.file.getName()); imageSizeLabel.setText (item.file.length() + " bytes"); imageIconLabel.setIcon (item.icon); setColorsForSelectionState (imageCellPrototype, isSelected); return imageCellPrototype; } else { FileItem item = (FileItem) value; // pouplate values fileNameLabel.setText (item.file.getName()); fileSizeLabel.setText (item.file.length() + " bytes"); setColorsForSelectionState (fileCellPrototype, isSelected); return fileCellPrototype; }}private void setColorsForSelectionState (Container prototype, boolean isSelected) { Component[] comps = prototype.getComponents(); for (int i=0; i<comps.length; i++) { if (isSelected) { comps[i].setForeground (listSelectionForeground); comps[i].setBackground (listSelectionBackground); } else { comps[i].setForeground (listForeground); comps[i].setBackground (listBackground); } } } }}
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