fileviewer.java

很好的学习swt的 sample 很好的学习swt的 sample

package org.eclipse.swt.examples.fileviewer;

/*
 * Copyright (c) 2000, 2002 IBM Corp.  All rights reserved.
 * This file is made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 */

import org.eclipse.swt.*;
import org.eclipse.swt.custom.*;
import org.eclipse.swt.dnd.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.program.*;
import org.eclipse.swt.widgets.*;

import java.io.*;
import java.text.*;
import java.util.*;

/**
 * File Viewer example
 */
public class FileViewer { 
 	private static ResourceBundle resourceBundle = ResourceBundle.getBundle("examples_fileviewer");

	private final static String DRIVE_A = "a:" + File.separator;
	private final static String DRIVE_B = "b:" + File.separator;

	/* UI elements */ 	
	private Display display; 
	private Shell shell;
	private ToolBar toolBar;

	private Label numObjectsLabel;
	private Label diskSpaceLabel;
	
	private File currentDirectory = null;
	private boolean initial = true;
	
	/* Drag and drop optimizations */
	private boolean isDragging = false; // if this app is dragging
	private boolean isDropping = false; // if this app is dropping

	private File[]  processedDropFiles = null; // so Drag only deletes what it needs to
	private File[]  deferredRefreshFiles = null;      // to defer notifyRefreshFiles while we do DND
	private boolean deferredRefreshRequested = false; // to defer notifyRefreshFiles while we do DND
	private ProgressDialog progressDialog = null; // progress dialog for locally-initiated operations

	/* Combo view */
	private static final String COMBODATA_ROOTS = "Combo.roots";
		// File[]: Array of files whose paths are currently displayed in the combo
	private static final String COMBODATA_LASTTEXT = "Combo.lastText";
		// String: Previous selection text string

	private Combo combo;

	/* Tree view */
	private IconCache iconCache = new IconCache();
	private static final String TREEITEMDATA_FILE = "TreeItem.file";
		// File: File associated with tree item
	private static final String TREEITEMDATA_IMAGEEXPANDED = "TreeItem.imageExpanded";
		// Image: shown when item is expanded
	private static final String TREEITEMDATA_IMAGECOLLAPSED = "TreeItem.imageCollapsed";
		// Image: shown when item is collapsed
	private static final String TREEITEMDATA_STUB = "TreeItem.stub";
		// Object: if not present or null then the item has not been populated

	private Tree tree;
	private Label treeScopeLabel;

	/* Table view */
	private static final DateFormat dateFormat = DateFormat.getDateTimeInstance(
		DateFormat.MEDIUM, DateFormat.MEDIUM);
	private static final String TABLEITEMDATA_FILE = "TableItem.file";
		// File: File associated with table row
	private static final String TABLEDATA_DIR = "Table.dir";
		// File: Currently visible directory
	private static final int[] tableWidths = new int[] {150, 60, 75, 150};
	private final String[] tableTitles = new String [] {
		FileViewer.getResourceString("table.Name.title"),
		FileViewer.getResourceString("table.Size.title"),
		FileViewer.getResourceString("table.Type.title"),
		FileViewer.getResourceString("table.Modified.title")
	};
	private Table table;
	private Label tableContentsOfLabel;

	/* Table update worker */
	// Control data
	private final Object workerLock = new Object();
		// Lock for all worker control data and state
	private volatile Thread  workerThread = null;
		// The worker's thread
	private volatile boolean workerStopped = false;
		// True if the worker must exit on completion of the current cycle
	private volatile boolean workerCancelled = false;
		// True if the worker must cancel its operations prematurely perhaps due to a state update

	// Worker state information -- this is what gets synchronized by an update
	private volatile File workerStateDir = null;

	// State information to use for the next cycle
	private volatile File workerNextDir = null;

	/* Simulate only flag */
	// when true, disables actual filesystem manipulations and outputs results to standard out
	private boolean simulateOnly = true;

	/**
	 * Runs main program.
	 */
	public static void main (String [] args) {
		Display display = new Display ();
		FileViewer application = new FileViewer();
		Shell shell = application.open(display);
		while (! shell.isDisposed()) {
			if (! display.readAndDispatch()) display.sleep();
		}
		application.close();
		display.dispose();
	}

	/**
	 * Opens the main program.
	 */
	public Shell open(Display display) {		
		// Create the window
		this.display = display;
		iconCache.initResources(display);
		shell = new Shell();
		createShellContents();
		notifyRefreshFiles(null);
		shell.open();
		return shell;
	}

	/**
	 * Closes the main program.
	 */
	void close() {
		workerStop();
		iconCache.freeResources();
	}
	
	/**
	 * Returns a string from the resource bundle.
	 * We don't want to crash because of a missing String.
	 * Returns the key if not found.
	 */
	static String getResourceString(String key) {
		try {
			return resourceBundle.getString(key);
		} catch (MissingResourceException e) {
			return key;
		} catch (NullPointerException e) {
			return "!" + key + "!";
		}			
	}

	/**
	 * Returns a string from the resource bundle and binds it
	 * with the given arguments. If the key is not found,
	 * return the key.
	 */
	static String getResourceString(String key, Object[] args) {
		try {
			return MessageFormat.format(getResourceString(key), args);
		} catch (MissingResourceException e) {
			return key;
		} catch (NullPointerException e) {
			return "!" + key + "!";
		}
	}

	/**
	 * Construct the UI
	 * 
	 * @param container the ShellContainer managing the Shell we are rendering inside
	 */
	private void createShellContents() {
		shell.setText(getResourceString("Title", new Object[] { "" }));	
		shell.setImage(iconCache.stockImages[iconCache.shellIcon]);
		Menu bar = new Menu(shell, SWT.BAR);
		shell.setMenuBar(bar);
		createFileMenu(bar);
		createHelpMenu(bar);

		GridLayout gridLayout = new GridLayout();
		gridLayout.numColumns = 3;
		gridLayout.marginHeight = gridLayout.marginWidth = 0;
		shell.setLayout(gridLayout);

		GridData gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
		gridData.widthHint = 185;
		createComboView(shell, gridData);
		gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
		gridData.horizontalSpan = 2;
		createToolBar(shell, gridData);

		SashForm sashForm = new SashForm(shell, SWT.NONE);
		sashForm.setOrientation(SWT.HORIZONTAL);
		gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.FILL_VERTICAL);
		gridData.horizontalSpan = 3;
		sashForm.setLayoutData(gridData);
		createTreeView(sashForm);
		createTableView(sashForm);
		sashForm.setWeights(new int[] { 2, 5 });

		numObjectsLabel = new Label(shell, SWT.BORDER);
		gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
		gridData.widthHint = 185;
		numObjectsLabel.setLayoutData(gridData);
		
		diskSpaceLabel = new Label(shell, SWT.BORDER);
		gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
		gridData.horizontalSpan = 2;
		diskSpaceLabel.setLayoutData(gridData);
	}
	
	/**
	 * Creates the File Menu.
	 * 
	 * @param parent the parent menu
	 */
	private void createFileMenu(Menu parent) {
		Menu menu = new Menu(parent);
		MenuItem header = new MenuItem(parent, SWT.CASCADE);
		header.setText(getResourceString("menu.File.text"));
		header.setMenu(menu);

		final MenuItem simulateItem = new MenuItem(menu, SWT.CHECK);
		simulateItem.setText(getResourceString("menu.File.SimulateOnly.text"));
		simulateItem.setSelection(simulateOnly);
		simulateItem.addSelectionListener(new SelectionAdapter () {
			public void widgetSelected(SelectionEvent e) {
				simulateOnly = simulateItem.getSelection();
			}
		});

		MenuItem item = new MenuItem(menu, SWT.PUSH);
		item.setText(getResourceString("menu.File.Close.text"));
		item.addSelectionListener(new SelectionAdapter () {
			public void widgetSelected(SelectionEvent e) {
				shell.close();
			}
		});
	}
	
	/**
	 * Creates the Help Menu.
	 * 
	 * @param parent the parent menu
	 */
	private void createHelpMenu(Menu parent) {
		Menu menu = new Menu(parent);
		MenuItem header = new MenuItem(parent, SWT.CASCADE);
		header.setText(getResourceString("menu.Help.text"));
		header.setMenu(menu);

		MenuItem item = new MenuItem(menu, SWT.PUSH);
		item.setText(getResourceString("menu.Help.About.text"));		
		item.addSelectionListener(new SelectionAdapter () {
			public void widgetSelected(SelectionEvent e) {
				MessageBox box = new MessageBox(shell, SWT.ICON_INFORMATION | SWT.OK);
				box.setText(getResourceString("dialog.About.title"));
				box.setMessage(getResourceString("dialog.About.description",
					new Object[] { System.getProperty("os.name") }));
				box.open();
			}
		});
	}

	/**
	 * Creates the toolbar
	 * 
	 * @param shell the shell on which to attach the toolbar
	 * @param layoutData the layout data
	 */
	private void createToolBar(final Shell shell, Object layoutData) {
		toolBar = new ToolBar(shell, SWT.NULL);
		toolBar.setLayoutData(layoutData);
		ToolItem item = new ToolItem(toolBar, SWT.SEPARATOR);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdParent]);
		item.setToolTipText(getResourceString("tool.Parent.tiptext"));
		item.addSelectionListener(new SelectionAdapter () {
			public void widgetSelected(SelectionEvent e) {
				doParent();
			}
		});
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdRefresh]);
		item.setToolTipText(getResourceString("tool.Refresh.tiptext"));
		item.addSelectionListener(new SelectionAdapter () {
			public void widgetSelected(SelectionEvent e) {
				doRefresh();
			}
		});
		SelectionAdapter unimplementedListener = new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				MessageBox box = new MessageBox(shell, SWT.ICON_INFORMATION | SWT.OK);
				box.setText(getResourceString("dialog.NotImplemented.title"));
				box.setMessage(getResourceString("dialog.ActionNotImplemented.description"));
				box.open();
			}
		};

		item = new ToolItem(toolBar, SWT.SEPARATOR);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdCut]);
		item.setToolTipText(getResourceString("tool.Cut.tiptext"));
		item.addSelectionListener(unimplementedListener);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdCopy]);
		item.setToolTipText(getResourceString("tool.Copy.tiptext"));
		item.addSelectionListener(unimplementedListener);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdPaste]);
		item.setToolTipText(getResourceString("tool.Paste.tiptext"));
		item.addSelectionListener(unimplementedListener);

		item = new ToolItem(toolBar, SWT.SEPARATOR);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdDelete]);
		item.setToolTipText(getResourceString("tool.Delete.tiptext"));
		item.addSelectionListener(unimplementedListener);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdRename]);
		item.setToolTipText(getResourceString("tool.Rename.tiptext"));
		item.addSelectionListener(unimplementedListener);

		item = new ToolItem(toolBar, SWT.SEPARATOR);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdSearch]);
		item.setToolTipText(getResourceString("tool.Search.tiptext"));
		item.addSelectionListener(unimplementedListener);
		item = new ToolItem(toolBar, SWT.PUSH);
		item.setImage(iconCache.stockImages[iconCache.cmdPrint]);
		item.setToolTipText(getResourceString("tool.Print.tiptext"));
		item.addSelectionListener(unimplementedListener);
	}

	/**
	 * Creates the combo box view.
	 * 
	 * @param parent the parent control
	 */
	private void createComboView(Composite parent, Object layoutData) {
		combo = new Combo(parent, SWT.NONE);
		combo.setLayoutData(layoutData);
		combo.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				final File[] roots = (File[]) combo.getData(COMBODATA_ROOTS);
				if (roots == null) return;
				int selection = combo.getSelectionIndex();
				if (selection >= 0 && selection < roots.length) {
					notifySelectedDirectory(roots[selection]);
				}
			}
			public void widgetDefaultSelected(SelectionEvent e) {
				final String lastText = (String) combo.getData(COMBODATA_LASTTEXT);
				String text = combo.getText();
				if (text == null) return;
				if (lastText != null && lastText.equals(text)) return;
				combo.setData(COMBODATA_LASTTEXT, text);
				notifySelectedDirectory(new File(text));
			}
		});
	}

	/**
	 * Creates the file tree view.
	 * 
	 * @param parent the parent control
	 */
	private void createTreeView(Composite parent) {
		Composite composite = new Composite(parent, SWT.NONE);
		GridLayout gridLayout = new GridLayout();
		gridLayout.numColumns = 1;
		gridLayout.marginHeight = gridLayout.marginWidth = 2;
		gridLayout.horizontalSpacing = gridLayout.verticalSpacing = 0;
		composite.setLayout(gridLayout);

		treeScopeLabel = new Label(composite, SWT.BORDER);
		treeScopeLabel.setText(FileViewer.getResourceString("details.AllFolders.text"));
		treeScopeLabel.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL));

		tree = new Tree(composite, SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL | SWT.SINGLE);
		tree.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.FILL_VERTICAL));

		tree.addSelectionListener(new SelectionListener() {
			public void widgetSelected(SelectionEvent event) {
				final TreeItem[] selection = tree.getSelection();
				if (selection != null && selection.length != 0) {
					TreeItem item = selection[0];
					File file = (File) item.getData(TREEITEMDATA_FILE);
				
					notifySelectedDirectory(file);
				}
			}
			public void widgetDefaultSelected(SelectionEvent event) {
				final TreeItem[] selection = tree.getSelection();
				if (selection != null && selection.length != 0) {
					TreeItem item = selection[0];
					item.setExpanded(true);
					treeExpandItem(item);
				}
			}
		});
		tree.addTreeListener(new TreeAdapter() {
			public void treeExpanded(TreeEvent event) {
				final TreeItem item = (TreeItem) event.item;
				final Image image = (Image) item.getData(TREEITEMDATA_IMAGEEXPANDED);
				if (image != null) item.setImage(image);
				treeExpandItem(item);
			}
			public void treeCollapsed(TreeEvent event) {
				final TreeItem item = (TreeItem) event.item;
				final Image image = (Image) item.getData(TREEITEMDATA_IMAGECOLLAPSED);
				if (image != null) item.setImage(image);
			}
		});
		createTreeDragSource(tree);
		createTreeDropTarget(tree);
	}

	/**
	 * Creates the Drag & Drop DragSource for items being dragged from the tree.
	 *