HtmlPanel class is a Swing
* component that can render a HTML DOM. It uses
* either {@link HtmlBlockPanel} or {@link FrameSetPanel}
* internally, depending on whether the document
* is determined to be a FRAMESET or not.
*
* Invoke method {@link #setDocument(Document, HtmlRendererContext)}
* in order to schedule a document for rendering.
*/
public class HtmlPanel extends JComponent implements FrameContext {
private final EventDispatch2 selectionDispatch = new SelectionDispatch();
private final javax.swing.Timer notificationTimer;
private final DocumentNotificationListener notificationListener;
private final Runnable notificationImmediateAction;
private static final int NOTIF_TIMER_DELAY = 300;
private volatile boolean isFrameSet = false;
private volatile NodeRenderer nodeRenderer = null;
private volatile NodeImpl rootNode;
private volatile int preferredWidth = -1;
private volatile Insets defaultMarginInsets = new Insets(8, 8, 8, 8);
private volatile int defaultOverflowX = RenderState.OVERFLOW_AUTO;
private volatile int defaultOverflowY = RenderState.OVERFLOW_SCROLL;
protected volatile HtmlBlockPanel htmlBlockPanel;
protected volatile FrameSetPanel frameSetPanel;
/**
* Constructs an HtmlPanel.
*/
public HtmlPanel() {
super();
this.setLayout(WrapperLayout.getInstance());
this.setOpaque(false);
this.notificationTimer = new javax.swing.Timer(NOTIF_TIMER_DELAY, new NotificationTimerAction());
this.notificationTimer.setRepeats(false);
this.notificationListener = new LocalDocumentNotificationListener();
this.notificationImmediateAction = new Runnable() {
public void run() {
processNotifications();
}
};
}
/**
* Sets a preferred width that serves as a hint in calculating
* the preferred size of the HtmlPanel. Note that
* the preferred size can only be calculated when a document is
* available, and it will vary during incremental rendering.
*
* This method currently does not have any effect when the * document is a FRAMESET. *
* Note also that setting the preferred width (to a value other
* than -1) will negatively impact performance.
*
* @param width The preferred width, or -1 to unset.
*/
public void setPreferredWidth(int width) {
this.preferredWidth = width;
HtmlBlockPanel htmlBlock = this.htmlBlockPanel;
if(htmlBlock != null) {
htmlBlock.setPreferredWidth(width);
}
}
/**
* If the current document is not a FRAMESET,
* this method scrolls the body area to the given location.
*
* This method should be called from the GUI thread. * @param bounds The bounds in the scrollable block area that should * become visible. * @param xIfNeeded If this parameter is true, scrolling will only occur if the * requested bounds are not currently visible horizontally. * @param yIfNeeded If this parameter is true, scrolling will only occur if the * requested bounds are not currently visible vertically. */ public void scrollTo(Rectangle bounds, boolean xIfNeeded, boolean yIfNeeded) { HtmlBlockPanel htmlBlock = this.htmlBlockPanel; if(htmlBlock != null) { htmlBlock.scrollTo(bounds, xIfNeeded, yIfNeeded); } } /** * Scrolls the body area to the node given, if it is * part of the current document. *
* This method should be called from the GUI thread.
* @param node A DOM node.
*/
public void scrollTo(org.w3c.dom.Node node) {
HtmlBlockPanel htmlBlock = this.htmlBlockPanel;
if(htmlBlock != null) {
htmlBlock.scrollTo(node);
}
}
/**
* Gets the root Renderable of
* the HTML block. It returns null
* for FRAMESETs.
*/
public BoundableRenderable getBlockRenderable() {
HtmlBlockPanel htmlBlock = this.htmlBlockPanel;
return htmlBlock == null ? null : htmlBlock.getRootRenderable();
}
/**
* Gets an instance of {@link FrameSetPanel} in case
* the currently rendered page is a FRAMESET.
*
* Note: This method should be invoked in the GUI thread.
* @return A FrameSetPanel instance or null
* if the document currently rendered is not a FRAMESET.
*/
public FrameSetPanel getFrameSetPanel() {
int componentCount = this.getComponentCount();
if(componentCount == 0) {
return null;
}
Object c = this.getComponent(0);
if(c instanceof FrameSetPanel) {
return (FrameSetPanel) c;
}
return null;
}
private void setUpAsBlock(UserAgentContext ucontext, HtmlRendererContext rcontext) {
HtmlBlockPanel shp = this.createHtmlBlockPanel(ucontext, rcontext);
shp.setPreferredWidth(this.preferredWidth);
shp.setDefaultMarginInsets(this.defaultMarginInsets);
shp.setDefaultOverflowX(this.defaultOverflowX);
shp.setDefaultOverflowY(this.defaultOverflowY);
this.htmlBlockPanel = shp;
this.frameSetPanel = null;
this.removeAll();
this.add(shp);
this.nodeRenderer = shp;
}
private void setUpFrameSet(NodeImpl fsrn) {
this.isFrameSet = true;
this.htmlBlockPanel = null;
FrameSetPanel fsp = this.createFrameSetPanel();
this.frameSetPanel = fsp;
this.nodeRenderer = fsp;
this.removeAll();
this.add(fsp);
fsp.setRootNode(fsrn);
}
/**
* Method invoked internally to create a {@link HtmlBlockPanel}.
* It is made available so it can be overridden.
*/
protected HtmlBlockPanel createHtmlBlockPanel(UserAgentContext ucontext, HtmlRendererContext rcontext) {
return new HtmlBlockPanel(java.awt.Color.WHITE, true, ucontext, rcontext, this);
}
/**
* Method invoked internally to create a {@link FrameSetPanel}.
* It is made available so it can be overridden.
*/
protected FrameSetPanel createFrameSetPanel() {
return new FrameSetPanel();
}
/**
* Scrolls the document such that x and y coordinates
* are placed in the upper-left corner of the panel.
*
* This method may be called outside of the GUI Thread. * @param x The x coordinate. * @param y The y coordinate. */ public void scroll(final int x, final int y) { if(EventQueue.isDispatchThread()) { this.scrollImpl(x, y); } else { EventQueue.invokeLater(new Runnable() { public void run() { scrollImpl(x, y); } }); } } public void scrollBy(final int x, final int y) { if(EventQueue.isDispatchThread()) { this.scrollByImpl(x, y); } else { EventQueue.invokeLater(new Runnable() { public void run() { scrollByImpl(x, y); } }); } } private void scrollImpl(int x, int y) { this.scrollTo(new Rectangle(x, y, 16, 16), false, false); } private void scrollByImpl(int xOffset, int yOffset) { HtmlBlockPanel bp = this.htmlBlockPanel; if(bp != null) { bp.scrollBy(xOffset, yOffset); } } /** * Clears the current document if any. * If called outside the GUI thread, the operation * will be scheduled to be performed in the GUI * thread. */ public void clearDocument() { if(java.awt.EventQueue.isDispatchThread()) { this.clearDocumentImpl(); } else { java.awt.EventQueue.invokeLater(new Runnable() { public void run() { HtmlPanel.this.clearDocumentImpl(); } }); } } private void clearDocumentImpl() { HTMLDocumentImpl prevDocument = (HTMLDocumentImpl) this.rootNode; if(prevDocument != null) { prevDocument.removeDocumentNotificationListener(this.notificationListener); } NodeRenderer nr = this.nodeRenderer; if(nr != null) { nr.setRootNode(null); } this.rootNode = null; this.htmlBlockPanel = null; this.nodeRenderer = null; this.isFrameSet = false; this.removeAll(); this.revalidate(); this.repaint(); } /** * Sets an HTML DOM node and invalidates the component so it is * rendered as soon as possible in the GUI thread. *
* If this method is called from a thread that is not the GUI * dispatch thread, the document is scheduled to be set later. * Note that {@link #setPreferredWidth(int) preferred size} * calculations should be done in the GUI dispatch thread for * this reason. * @param node This should * normally be a Document instance obtained with * {@link org.lobobrowser.html.parser.DocumentBuilderImpl}. *
* @param rcontext A renderer context. * @see org.lobobrowser.html.parser.DocumentBuilderImpl#parse(org.xml.sax.InputSource) * @see org.lobobrowser.html.test.SimpleHtmlRendererContext */ public void setDocument(final Document node, final HtmlRendererContext rcontext) { if(java.awt.EventQueue.isDispatchThread()) { this.setDocumentImpl(node, rcontext); } else { java.awt.EventQueue.invokeLater(new Runnable() { public void run() { HtmlPanel.this.setDocumentImpl(node, rcontext); } }); } } /** * Scrolls to the element identified by the given ID in * the current document. *
* If this method is invoked outside the GUI thread, * the operation is scheduled to be performed as soon * as possible in the GUI thread. * @param nameOrId The name or ID of the element in the document. */ public void scrollToElement(final String nameOrId) { if(EventQueue.isDispatchThread()) { this.scrollToElementImpl(nameOrId); } else { EventQueue.invokeLater(new Runnable() { public void run() { scrollToElementImpl(nameOrId); } }); } } private void scrollToElementImpl(String nameOrId) { NodeImpl node = this.rootNode; if(node instanceof HTMLDocumentImpl) { HTMLDocumentImpl doc = (HTMLDocumentImpl) node; org.w3c.dom.Element element = doc.getElementById(nameOrId); if(element != null) { this.scrollTo(element); } } } private void setDocumentImpl(Document node, HtmlRendererContext rcontext) { // Expected to be called in the GUI thread. if(!(node instanceof HTMLDocumentImpl)) { throw new IllegalArgumentException("Only nodes of type HTMLDocumentImpl are currently supported. Use DocumentBuilderImpl."); } HTMLDocumentImpl prevDocument = (HTMLDocumentImpl) this.rootNode; if(prevDocument != null) { prevDocument.removeDocumentNotificationListener(this.notificationListener); } HTMLDocumentImpl nodeImpl = (HTMLDocumentImpl) node; nodeImpl.addDocumentNotificationListener(this.notificationListener); this.rootNode = nodeImpl; NodeImpl fsrn = this.getFrameSetRootNode(nodeImpl); boolean newIfs = fsrn != null; if(newIfs != this.isFrameSet || this.getComponentCount() == 0) { this.isFrameSet = newIfs; if(newIfs) { this.setUpFrameSet(fsrn); } else { this.setUpAsBlock(rcontext.getUserAgentContext(), rcontext); } } NodeRenderer nr = this.nodeRenderer; if(nr != null) { // These subcomponents should take care // of revalidation. if(newIfs) { nr.setRootNode(fsrn); } else { nr.setRootNode(nodeImpl); } } else { this.invalidate(); this.validate(); this.repaint(); } } /** * Renders HTML given as a string. * @param htmlSource The HTML source code. * @param uri A base URI used to resolve item URIs. * @param rcontext The {@link HtmlRendererContext} instance. * @see org.lobobrowser.html.test.SimpleHtmlRendererContext * @see #setDocument(Document, HtmlRendererContext) */ public void setHtml(String htmlSource, String uri, HtmlRendererContext rcontext) { try { DocumentBuilderImpl builder = new DocumentBuilderImpl(rcontext.getUserAgentContext(), rcontext); Reader reader = new StringReader(htmlSource); try { InputSourceImpl is = new InputSourceImpl(reader, uri); Document document = builder.parse(is); this.setDocument(document, rcontext); } finally { reader.close(); } } catch(java.io.IOException ioe) { throw new IllegalStateException("Unexpected condition.", ioe); } catch(org.xml.sax.SAXException se) { throw new IllegalStateException("Unexpected condition.", se); } } /** * Gets the HTML DOM node currently rendered if any. */ public NodeImpl getRootNode() { return this.rootNode; } private boolean resetIfFrameSet() { NodeImpl nodeImpl = this.rootNode; NodeImpl fsrn = this.getFrameSetRootNode(nodeImpl); boolean newIfs = fsrn != null; if(newIfs != this.isFrameSet || this.getComponentCount() == 0) { this.isFrameSet = newIfs; if(newIfs) { this.setUpFrameSet(fsrn); NodeRenderer nr = this.nodeRenderer; nr.setRootNode(fsrn); // Set proper bounds and repaint. this.validate(); this.repaint(); return true; } } return false; } private NodeImpl getFrameSetRootNode(NodeImpl node) { if(node instanceof Document) { ElementImpl element = (ElementImpl) ((Document) node).getDocumentElement(); if(element != null && "HTML".equalsIgnoreCase(element.getTagName())) { return this.getFrameSet(element); } else { return this.getFrameSet(node); } } else { return null; } } private NodeImpl getFrameSet(NodeImpl node) { NodeImpl[] children = node.getChildrenArray(); if(children == null) { return null; } int length = children.length; NodeImpl frameSet = null; for(int i = 0; i < length; i++) { NodeImpl child = children[i]; if(child instanceof Text) { // Ignore } else if(child instanceof ElementImpl) { String tagName = child.getNodeName(); if("HEAD".equalsIgnoreCase(tagName) || "NOFRAMES".equalsIgnoreCase(tagName) || "TITLE".equalsIgnoreCase(tagName) || "META".equalsIgnoreCase(tagName) || "SCRIPT".equalsIgnoreCase(tagName) || "NOSCRIPT".equalsIgnoreCase(tagName)) { // ignore it } else if("FRAMESET".equalsIgnoreCase(tagName)) { frameSet = child; break; } else { if(this.hasSomeHtml((ElementImpl) child)) { return null; } } } } return frameSet; } private boolean hasSomeHtml(ElementImpl element) { String tagName = element.getTagName(); if("HEAD".equalsIgnoreCase(tagName) || "TITLE".equalsIgnoreCase(tagName) || "META".equalsIgnoreCase(tagName)) { return false; } NodeImpl[] children = element.getChildrenArray(); if(children != null) { int length = children.length; for(int i = 0; i < length; i++) { NodeImpl child = children[i]; if(child instanceof Text) { String textContent = ((Text) child).getTextContent(); if(textContent != null && !"".equals(textContent.trim())) { return false; } } else if(child instanceof ElementImpl) { if(this.hasSomeHtml((ElementImpl) child)) { return false; } } } } return true; } /** * Internal method used to expand the selection to the given point. *
* Note: This method should be invoked in the GUI thread. */ public void expandSelection(RenderableSpot rpoint) { HtmlBlockPanel block = this.htmlBlockPanel; if(block != null) { block.setSelectionEnd(rpoint); block.repaint(); this.selectionDispatch.fireEvent(new SelectionChangeEvent(this, block.isSelectionAvailable())); } } /** * Internal method used to reset the selection so that * it is empty at the given point. This is what is called * when the user clicks on a point in the document. *
* Note: This method should be invoked in the GUI thread. */ public void resetSelection(RenderableSpot rpoint) { HtmlBlockPanel block = this.htmlBlockPanel; if(block != null) { block.setSelectionStart(rpoint); block.setSelectionEnd(rpoint); block.repaint(); } this.selectionDispatch.fireEvent(new SelectionChangeEvent(this, false)); } /** * Gets the selection text. *
* Note: This method should be invoked in the GUI thread. */ public String getSelectionText() { HtmlBlockPanel block = this.htmlBlockPanel; if(block == null) { return null; } else { return block.getSelectionText(); } } /** * Gets a DOM node enclosing the selection. The node returned should * be the inner-most node that encloses both selection start and end * points. Note that the selection end point may be just outside of * the selection. *
* Note: This method should be invoked in the GUI thread.
* @return A node enclosing the current selection, or null
* if there is no such node. It also returns null
* for FRAMESETs.
*/
public org.w3c.dom.Node getSelectionNode() {
HtmlBlockPanel block = this.htmlBlockPanel;
if(block == null) {
return null;
}
else {
return block.getSelectionNode();
}
}
/**
* Returns true only if the current block has a selection.
* This method has no effect in FRAMESETs at the moment.
*/
public boolean hasSelection() {
HtmlBlockPanel block = this.htmlBlockPanel;
if(block == null) {
return false;
}
else {
return block.hasSelection();
}
}
/**
* Copies the current selection, if any, into the clipboard.
* This method has no effect in FRAMESETs at the moment.
*/
public boolean copy() {
HtmlBlockPanel block = this.htmlBlockPanel;
if(block != null) {
return block.copy();
}
else {
return false;
}
}
/**
* Adds listener of selection changes. Note that it does
* not have any effect on FRAMESETs.
* @param listener An instance of {@link SelectionChangeListener}.
*/
public void addSelectionChangeListener(SelectionChangeListener listener) {
this.selectionDispatch.addListener(listener);
}
/**
* Removes a listener of selection changes that was
* previously added.
*/
public void removeSelectionChangeListener(SelectionChangeListener listener) {
this.selectionDispatch.removeListener(listener);
}
/**
* Sets the default margin insets. Note that in the root block,
* the margin behaves like padding.
*
* This method has no effect on FRAMESETs. * @param insets The default margin insets. */ public void setDefaultMarginInsets(Insets insets) { this.defaultMarginInsets = insets; HtmlBlockPanel block = this.htmlBlockPanel; if(block != null) { block.setDefaultMarginInsets(insets); } } /** * Sets the default horizontal overflow. *
* This method has no effect on FRAMESETs. * @param overflow See {@link org.lobobrowser.html.style.RenderState}. */ public void setDefaultOverflowX(int overflow) { this.defaultOverflowX = overflow; HtmlBlockPanel block = this.htmlBlockPanel; if(block != null) { block.setDefaultOverflowX(overflow); } } /** * Sets the default vertical overflow. *
* This method has no effect on FRAMESETs. * @param overflow See {@link org.lobobrowser.html.style.RenderState}. */ public void setDefaultOverflowY(int overflow) { this.defaultOverflowY = overflow; HtmlBlockPanel block = this.htmlBlockPanel; if(block != null) { block.setDefaultOverflowY(overflow); } } private ArrayList notifications = new ArrayList(1); private void addNotification(DocumentNotification notification) { // This can be called in a random thread. ArrayList notifs = this.notifications; synchronized(notifs) { notifs.add(notification); } if(EventQueue.isDispatchThread()) { // In this case we want the notification to be processed // immediately. However, we don't want potential recursions // to occur when a Javascript property is set in the GUI thread. // Additionally, many property values may be set in one // event block. EventQueue.invokeLater(this.notificationImmediateAction); } else { this.notificationTimer.restart(); } } /** * Invalidates the layout of the given node and schedules it * to be layed out later. Multiple invalidations may be * processed in a single document layout. */ public void delayedRelayout(NodeImpl node) { ArrayList notifs = this.notifications; synchronized(notifs) { notifs.add(new DocumentNotification(DocumentNotification.SIZE, node)); } this.notificationTimer.restart(); } private void processNotifications() { // This is called in the GUI thread. ArrayList notifs = this.notifications; DocumentNotification[] notifsArray; synchronized(notifs) { int size = notifs.size(); if(size == 0) { return; } notifsArray = new DocumentNotification[size]; notifsArray = (DocumentNotification[]) notifs.toArray(notifsArray); notifs.clear(); } int length = notifsArray.length; for(int i = 0; i < length; i++) { DocumentNotification dn = notifsArray[i]; if(dn.node instanceof HTMLFrameSetElement && this.htmlBlockPanel != null) { if(this.resetIfFrameSet()) { // Revalidation already taken care of. return; } } } HtmlBlockPanel blockPanel = this.htmlBlockPanel; if(blockPanel != null) { blockPanel.processDocumentNotifications(notifsArray); } FrameSetPanel frameSetPanel = this.frameSetPanel; if(frameSetPanel != null) { frameSetPanel.processDocumentNotifications(notifsArray); } } private class SelectionDispatch extends EventDispatch2 { /* (non-Javadoc) * @see org.xamjwg.util.EventDispatch2#dispatchEvent(java.util.EventListener, java.util.EventObject) */ protected void dispatchEvent(EventListener listener, EventObject event) { ((SelectionChangeListener) listener).selectionChanged((SelectionChangeEvent) event); } } private class LocalDocumentNotificationListener implements DocumentNotificationListener { public void allInvalidated() { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.GENERIC, null)); } public void invalidated(NodeImpl node) { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.GENERIC, node)); } public void lookInvalidated(NodeImpl node) { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.LOOK, node)); } public void positionInvalidated(NodeImpl node) { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.POSITION, node)); } public void sizeInvalidated(NodeImpl node) { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.SIZE, node)); } public void externalScriptLoading(NodeImpl node) { // Ignorable here. } public void nodeLoaded(NodeImpl node) { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.GENERIC, node)); } public void structureInvalidated(NodeImpl node) { HtmlPanel.this.addNotification(new DocumentNotification(DocumentNotification.GENERIC, node)); } } private class NotificationTimerAction implements java.awt.event.ActionListener { public void actionPerformed(ActionEvent e) { HtmlPanel.this.processNotifications(); } } }