helpdialog.java

具有不同语法高亮的编辑器实例

		// will try to expand each node as we go along to be sure we hit all
		// possible nodes.
		for (int i=0; i<tocTree.getRowCount(); i++) {
			DefaultMutableTreeNode temp = (DefaultMutableTreeNode)tocTree.
								getPathForRow(i).getLastPathComponent();
			tocTree.expandRow(i);
			HelpTreeNode htn = (HelpTreeNode)temp.getUserObject();
			if (htn.url!=null && htn.url.equals(url)) {
				tocTree.setSelectionRow(i);
				tocTree.scrollRowToVisible(i);
				return;
			}
		}

		// If the page wasn't found, tell the user so.
		ResourceBundle msg = getHelpBundle();
		JOptionPane.showMessageDialog(this,
							msg.getString("PageNotFound"),
							msg.getString("Error"),
							JOptionPane.ERROR_MESSAGE);
		msg = null; // May help GC.

	}


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


	/**
	 * Sets the label on the "Index" tab.
 	 *
	 * @param text The text for the "Index" tab.
	 * @see #getIndexTabText
	 */
	public void setIndexTabText(String text) {
		tabbedPane.setTitleAt(1, text);
	}


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


	/**
	 * Sets the text label above the "Type in a keyword to find" text boxes.
	 *
	 * @param text The text label.
	 * @see #getKeywordFieldLabelText
	 */
	public void setKeywordFieldLabelText(String text) {
		keywordToFindLabel.setText(text);
		keywordToFindLabel2.setText(text);
	}


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


	/**
	 * Sets the label on the "List Topics" button on the Search panels.
 	 *
	 * @param text The text for the "List Topics" button.
	 * @see #getListTopicsButtonText
	 */
	public void setListTopicsButtonText(String text) {
		listTopicsButton.setText(text);
	}


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


	/**
	 * Sets the label on the "Search" tab.
 	 *
	 * @param text The text for the "Search" tab.
	 * @see #getSearchTabText
	 */
	public void setSearchTabText(String text) {
		tabbedPane.setTitleAt(2, text);
	}


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


	/**
	 * Sets the text label above the "Select topic to display" text box.
	 *
	 * @param text The text label.
	 * @see #getTopicToDisplayFieldLabelText
	 */
	public void setTopicToDisplayFieldLabelText(String text) {
		topicToDisplayLabel.setText(text);
	}


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


	/**
	 * Helper function to validate that a given node is indeed an Attribute
	 * node with the specified name.
	 *
	 * @param node The node to check.
	 * @param name The name the node should have.
	 * @return Whether the specified node is an Attribute node with the
	 *         specified name.
	 */
	private final boolean validateAttributeNode(Node node, String name) {
		return (node!=null && node.getNodeType()==Node.ATTRIBUTE_NODE &&
				node.getNodeName().equals(name));
	}


/*****************************************************************************/
/****************** INNER CLASSES ********************************************/
/*****************************************************************************/


	/**
	 * Listens for events in the help dialog.
	 */
	protected class HelpListener extends MouseAdapter
						implements ChangeListener,
						HyperlinkListener, DocumentListener,
						KeyListener, TreeSelectionListener {

		public void changedUpdate(DocumentEvent e) {
		}

		/**
		 * Called whenever the user clicks on a hyperlink in editorPane.
		 */
		public void hyperlinkUpdate(HyperlinkEvent e) {

			HyperlinkEvent.EventType eventType = e.getEventType();

			if (eventType.equals(HyperlinkEvent.EventType.ACTIVATED)) {
				// Yes, you want this to update the memory of pages visited.
				updateHistory = true;
				highlightSearchString = false;
				// This is a hack so that, for their href, they can specify a "relative path"
				// to any HTML help, which especially comes in handy in jar files.
				URL url = e.getURL();
				if (url==null) {
					try {
						url = new URL("file://" + baseURL.getPath() + e.getDescription());
					} catch (MalformedURLException mue) {
						guiApp.displayException(HelpDialog.this, mue);
					}
				}
				String anchor = url.getRef(); // null if no reference.
				if (anchor!=null) {
					try {
						String protocol = url.getProtocol();
						if (protocol==null || protocol.equals(""))
							protocol = "file://";
						String urlString = "file://" + url.getPath();
						url = new URL(urlString); // No anchor.
					} catch (MalformedURLException mue) {
						mue.printStackTrace();
					}
				}
				setHelpPageURL(url);
				if (anchor!=null)
					editorPane.scrollToReference(anchor);
			}

			else if (eventType.equals(HyperlinkEvent.EventType.ENTERED)) {
				editorPane.setToolTipText(e.getDescription());
			}

			else if (eventType.equals(HyperlinkEvent.EventType.EXITED)) {
				editorPane.setToolTipText(null);
			}

		}

		/**
		 * Called whenever indexField or searchField's contents are
		 * inserted into.
		 */
		public void insertUpdate(DocumentEvent e) {
			Document doc = e.getDocument();
			// If it was the index text field that changed...
			if ( doc.equals(indexField.getDocument()) ) {
				// Find closest match to entered text in index list and highlight it.
				int closestMatch = indexList.getNextMatch(
						indexField.getText(), 0, Position.Bias.Forward);
				if (closestMatch != -1) {
					indexList.setSelectedIndex(closestMatch);
					indexList.ensureIndexIsVisible(indexList.getSelectedIndex());
				}
			}
			// If it was the search text field that changed...
			else if ( doc.equals(searchField.getDocument()) ) {
				// Ensure that the "List Topics" button is enabled.
				listTopicsButton.setEnabled(true);
			}
		}

		/**
		 * Called whenever the user presses a key in indexField or searchField.
		 */
		public void keyPressed(KeyEvent e) {

			// The only keypress we're interested in is the "Enter" key.
			if ( e.getKeyCode() == KeyEvent.VK_ENTER ) {

				Object source = e.getSource();

				// If they pressed Enter while in the index tab, load the
				// help page currently selected.
				if ( source.equals(indexField) || source.equals(indexList) ) {
					if (indexList.getSelectedIndex()!=-1)
						loadSelectedHelpPageIndex();
				}

				// If they press Enter while in searchField, display a list
				// of Help topics.
				else if (source.equals( searchField )) {
					searchString = searchField.getText();	// Remember the searched-for text.
					if (!searchString.equals(""))
						populateSearchList();
				}

				// If they press Enter while in searchList, display the
				// help topic they choose.
				else if (source.equals( searchList )) {
					if (indexList.getSelectedIndex()!=-1)
						loadSelectedHelpPageSearch();
				}

				// If they press enter while on an expandable node in the
				// tocTree, toggle it's expandedness.
				else if (source.equals( tocTree )) {
					int row = tocTree.getMaxSelectionRow();
					// These are okay since tree is single-selection.
					if (tocTree.isExpanded(row)==true)
						tocTree.collapseRow(row);
					else
						tocTree.expandRow(row);
				}

			} // End of if ( e.getKeyCode() == KeyEvent.VK_ENTER ).

		}

		public void keyReleased(KeyEvent e) {
		}

		public void keyTyped(KeyEvent e) {
		}

		/**
		 * We're listening for when the user clicks in one of our components.
		 */
		public void mouseClicked(MouseEvent e) {
			// They must double-click for anything to happen.
			if (e.getClickCount()==2) {
				// If they double-click in the index panel's JList,
				// load the clicked-on help page.
				if (e.getComponent().equals(indexList))
					loadSelectedHelpPageIndex();
				// If they double-click in the search panel's JList,
				// load the clicked-on help page.
				else if (e.getComponent().equals(searchList))
					loadSelectedHelpPageSearch();
			} // End of if (e.getClickCount()==2).
		}

		/**
		 * Called whenever indexField or searchField's contents are shortened.
		 */
		public void removeUpdate(DocumentEvent e) {
			Document doc = e.getDocument();
			// If it was the index text field that changed...
			if ( doc.equals(indexField.getDocument()) ) {
				// Find closest match to entered text in index list and
				// highlight it.
				int closestMatch = indexList.getNextMatch(
						indexField.getText(), 0, Position.Bias.Forward);
				if (closestMatch != -1) {
					indexList.setSelectedIndex(closestMatch);
					indexList.ensureIndexIsVisible(indexList.getSelectedIndex());
				}
			}
			// If it was the search text field that changed...
			else if ( doc.equals(searchField.getDocument()) ) {
				// If there is no more text in the search field,
				// disable the "List Topics" button.
				if (doc.getLength() == 0)
					listTopicsButton.setEnabled(false);
			}
		}

		/**
		 * Called whenever the user clicks on the Contents, Index, or
		 * Search tabs.
		 */
		public void stateChanged(ChangeEvent e) {
			int selection = ((JTabbedPane)e.getSource()).getSelectedIndex();
			JTextField field = null;
			// If they selected the Index or Search tab, select the top
			// text field.
			if (selection==1)
				field = indexField;
			else if (selection==2)
				field = searchField;
			if (field!=null) {
				final JTextField field2 = field; // Must be final...
				SwingUtilities.invokeLater(new Runnable() {
					public void run() {
						field2.requestFocusInWindow();
						field2.selectAll();
					}
				});
			}
		}

		/**
		 * Called whenever an item in the TOC tree is selected/deselected.
		 * This will display the help HTML corresponding to the TOC tree node
		 * selected in the right-hand pane.
		 */
		public void valueChanged(TreeSelectionEvent tse) {

			// Get the node they clicked on.
			DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode)
							tocTree.getLastSelectedPathComponent();

			// Selected node could be null if they selected a leaf, then
			// collapsed its parent tree node, leaving "no node" selected.
			if (selectedNode==null)
				return;
			HelpTreeNode htn = (HelpTreeNode)selectedNode.getUserObject();

			// Now, set the html in the right-hand pane to be the page
			// associated with this node.  NOTE: Must check for null URL's
			// as often, branch nodes don't have HTML associated with them.
			if (htn.url != null) {

				// As we support both plain text and HTML as help pages,
				// first check whether our text should be displayed as HTML.
				// We must re-set the IgnoreCharsetDirective property as
				// setContentType() gives us a new document.
				String contentType = guessContentType(htn.url.getPath());
				if (!contentType.equals(editorPane.getContentType())) {
					editorPane.setContentType(contentType);
					//editorPane.setDocument(editorPane.getEditorKit().createDefaultDocument());
					// The Document class does not yet handle charsets properly -
					// without the line below, you'll get a CharSetChangedException...
					editorPane.getDocument().putProperty("IgnoreCharsetDirective", Boolean.TRUE);
				}

				String allText = getContents(htn);

				// If the document is HTML, ensure that the it uses the
				// correct base URL so links work.
				Document document = editorPane.getDocument();
				if (document instanceof HTMLDocument) {
					HTMLDocument htmldoc = (HTMLDocument)document;
					htmldoc.setBase(baseURL);
				}

				editorPane.setText(allText);
				editorPane.setCaretPosition(0);

				// If they want to remember this page in the history...
				if (updateHistory || clickedOnTOCTree) {
					// This will be the "last" page.  Remove all pages
					// ahead of the current page and replace them with
					//this one.
					while (history.size()-1 > historyPos)
						history.remove(history.size()-1);
					history.add(htn);
					historyPos++;
					// The user can definitely go backward and not forward.
					backButton.setEnabled(true);
					forwardButton.setEnabled(false);
				}

				// Next time through, we'll assume we clicked on tocTree
				// unless told otherwise
				clickedOnTOCTree = true;

			} // End of if (htn.url != null).

		}

	}


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

}