filechoosericonmanager.java

具有不同语法高亮的编辑器实例

/*
 * 06/24/2005
 *
 * FileSystemIconManager.java - Manages icons for RTextFileChooser and
 * FileSystemTree.
 * Copyright (C) 2005 Robert Futrell
 * [e-mail]
 * www.website.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
package org.fife.ui.rtextfilechooser;

import java.io.File;
import java.util.HashMap;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.UIManager;
import javax.swing.filechooser.FileSystemView;


class FileChooserIconManager {

	protected Icon folderIcon;
	protected Icon hardDriveIcon;
	protected Icon floppyDriveIcon;
	protected Icon computerIcon;
	protected Icon fileIcon;

	private static final FileSystemView fileSystemView = FileSystemView.
												getFileSystemView();
	private HashMap iconCache;


/*****************************************************************************/


	public FileChooserIconManager() {
		iconCache = new HashMap(50);
		createDefaultIcons();
	}


/*****************************************************************************/


	/**
	 * Clears the icon cache.  Use this if you want to save memory between
	 * displays of the file tree.
	 */
	public void clearIconCache() {
		iconCache.clear();
	}


/*****************************************************************************/


	/**
	 * Creates the icons used by this file chooser.  This method can be
	 * called when the user changes the Look and Feel, and icons used in this
	 * file chooser will change to reflect the new Look and Feel.
	 */
	protected void createDefaultIcons() {

		// Now, on Windows, FileSystemView.getSystemIcon throws an exception
		// if you pass it a file that doesn't exist.  So, we need to have
		// a file that we KNOW is a directory (and not hidden, etc.) to use
		// when we check for the system icon.  Since there is no
		// File.createTempDirectory method, we must create a temporary file,
		// delete it, then recreate it as a directory...
		try {
			File temp = File.createTempFile("FileSystemTree", ".tmp");
			temp.delete();
			temp.mkdir();
			if (temp.isDirectory()) {
				folderIcon = FileSystemView.getFileSystemView().
											getSystemIcon(temp);
				temp.delete();
			}
		} catch (Exception e) {}

		// Get file chooser icons for folders, hard drives, and floppies.
		// We only need the floppy drive icon if the getSystemIcon above
		// returned null.
		if (folderIcon==null)
			folderIcon  = UIManager.getIcon("FileView.directoryIcon");
		hardDriveIcon    = UIManager.getIcon("FileView.hardDriveIcon");
		floppyDriveIcon  = UIManager.getIcon("FileView.floppyDriveIcon");
		fileIcon		  = UIManager.getIcon("FileView.fileIcon");

		// If UIManager returned null for any of the above, just get ones
		// we drew ourselves.
		String path = "org/fife/ui/rtextfilechooser/images/";
		ClassLoader cl = this.getClass().getClassLoader();
		if (folderIcon==null)
			folderIcon = loadIcon(cl, path + "directory.gif");
		if (hardDriveIcon==null)
			hardDriveIcon = loadIcon(cl, path + "harddrive.gif");
		if (floppyDriveIcon==null)
			floppyDriveIcon = loadIcon(cl, path + "floppydrive.gif");
		if (fileIcon==null)
			fileIcon = loadIcon(cl, path + "file.gif");

	}


/*****************************************************************************/


	/**
	 * Returns the standard folder icon.  This is basically a hack to get the
	 * folder icon without looking through/saving to the icon cache (e.g., for
	 * <code>DirectoryTree</code>).
	 *
	 * @return The icon for folders.
	 */
	public Icon getFolderIcon() {
		return folderIcon;
	}


/*****************************************************************************/


	/**
	 * Returns the icon used for this type of file by this file chooser.
	 *
	 * @param f The file for which you want to get its icon.
	 * @return The icon used.
	 */
	public Icon getIcon(File f) {

		Icon icon = null;

		if (f != null) {

			// First check to see if we've already got this
			// icon and cached it.
			icon = (Icon)iconCache.get(f);
			if (icon!=null)
				return icon;

			// See if the system has an icon for this file.
			try {
				icon = fileSystemView.getSystemIcon(f);
			} catch (/*FileNotFound*/Exception fnfe) {
				// This happens, for example, on Windows when no such
				// file "f" exists - the FileSystemView must check for
				// the existance of the icon first.
				//fnfe.printStackTrace();
				// Leave icon as null, it'll get set below.
			}

			// If it didn't, see if it matches one of our defaults.
			if (icon==null) {
				if (fileSystemView.isFloppyDrive(f)) {
					icon = floppyDriveIcon;
				}
				else if (fileSystemView.isDrive(f)) {
					icon = hardDriveIcon;
				}
				else if (fileSystemView.isComputerNode(f)) {
					icon = computerIcon;
				}
				else if (f.isDirectory()) {
					icon = folderIcon;
				}
				else { // Must be a regular file.
					icon = fileIcon;
				}
			}

			// Remember the icon for this file.
			iconCache.put(f, icon);

		}

		return icon;

	}


/*****************************************************************************/


	/**
	 * Creates and returns an icon from an image on disk.
	 *
	 * @param cl The classloader to locate the resource.
	 * @param file The file name.
	 * @return The icon.
	 */
	private static Icon loadIcon(ClassLoader cl, String file) {
		return new ImageIcon(cl.getResource(file));
	}


/*****************************************************************************/

}