- /*
- * @(#)BasicHTML.java 1.3 01/11/29
- *
- * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
- package javax.swing.plaf.basic;
-
- import java.io.*;
- import java.awt.*;
-
- import javax.swing.*;
- import javax.swing.text.*;
- import javax.swing.text.html.*;
-
- /**
- * Support for providing html views for the swing components.
- * This translates a simple html string to a javax.swing.text.View
- * implementation that can render the html and provide the necessary
- * layout semantics.
- *
- * @author Timothy Prinzing
- * @version 1.3 11/29/01
- */
- /*public*/ class BasicHTML {
-
- /**
- * Create an html renderer for the given component and
- * string of html.
- */
- public static View createHTMLView(JComponent c, String html) {
- HTMLEditorKit kit = getFactory();
- Document doc = kit.createDefaultDocument();
- Reader r = new StringReader(html);
- try {
- kit.read(r, doc, 0);
- } catch (Throwable e) {
- }
- ViewFactory f = kit.getViewFactory();
- View hview = f.create(doc.getDefaultRootElement());
- View v = new Renderer(c, f, hview);
- return v;
- }
-
- /**
- * Check the given string to see if it should trigger the
- * html rendering logic.
- */
- public static boolean isHTMLString(String s) {
- if (s != null) {
- return s.startsWith("<html>");
- }
- return false;
- }
-
- /**
- * Stash the HTML render for the given text into the client
- * properties of the given JComponent. If the given text is
- * <em>NOT HTML</em> the property will be cleared of any
- * renderer.
- * <p>
- * This method is useful for ComponentUI implementations
- * that are static (i.e. shared) and get their state
- * entirely from the JComponent.
- */
- public static void updateRenderer(JComponent c, String text) {
- View value = null;
- String key = null;
- if (BasicHTML.isHTMLString(text)) {
- value = BasicHTML.createHTMLView(c, text);
- }
- c.putClientProperty(BasicHTML.propertyKey, value);
- }
-
- /**
- * Key to use for the html renderer when stored as a
- * client property of a JComponent.
- */
- public static final String propertyKey = "html";
-
- static HTMLEditorKit getFactory() {
- if (basicHTMLFactory == null) {
- basicHTMLFactory = new BasicEditorKit();
-
- // Ideally you would create a new StyleSheet and call
- // newSS.addStyleSheet(basicHTMLFactory.getStyleSheet()),
- // but addStyleSheet is package private:(
- // Also, we can't use the basic editor kit because it uses
- // the sharedStyles static we are trying to initialize!!
- // It might be better to create a StyleSheet directly, but
- // currently we still leverage the defaults.
- EditorKit tmpKit = new HTMLEditorKit();
- HTMLDocument doc = (HTMLDocument) tmpKit.createDefaultDocument();
- sharedStyles = doc.getStyleSheet();
- try {
- StringReader r = new StringReader(styleChanges);
- sharedStyles.loadRules(r, null);
- } catch (Throwable e) {
- // don't want to die in static initialization...
- // just display things wrong.
- }
- }
- return basicHTMLFactory;
- }
-
- /**
- * The source of the html renderers
- */
- private static HTMLEditorKit basicHTMLFactory;
-
- private static StyleSheet sharedStyles;
-
- /**
- * Overrides to the default stylesheet. Should consider
- * just creating a completely fresh stylesheet.
- */
- private static final String styleChanges =
- "p { margin-top: 0; margin-bottom: 0; margin-left: 0; margin-right: 0 }" +
- "body { margin-top: 0; margin-bottom: 0; margin-left: 0; margin-right: 0 }";
-
- /**
- * The views produced for the ComponentUI implementations aren't
- * going to be edited and don't need full html support. This kit
- * alters the HTMLEditorKit to try and trim things down a bit.
- * It does the following:
- * <ul>
- * <li>It doesn't produce elements for things like comments,
- * head, title, unknown tags, etc.
- * <li>It shares the StyleSheet across all the documents.
- * <li>It installs a different set of css settings from the default
- * provided by HTMLEditorKit.
- * </ul>
- */
- static class BasicEditorKit extends HTMLEditorKit {
-
- public Document createDefaultDocument() {
- Document doc = new BasicDocument(sharedStyles);
- return doc;
- }
-
- }
-
- /**
- * This must be subclassed to provide a different HTMLReader
- * implementation.
- */
- static class BasicDocument extends HTMLDocument {
-
- BasicDocument(StyleSheet s) {
- super(s);
- }
-
- public HTMLEditorKit.ParserCallback getReader(int pos) {
- HTMLReader reader = new BasicReader(pos);
- return reader;
- }
-
- class BasicReader extends HTMLReader {
-
- public BasicReader(int offset) {
- super(offset);
- TagAction ignore = new TagAction();
- registerTag(HTML.Tag.HEAD, ignore);
- }
- }
-
- }
-
- /**
- * Root text view that acts as an HTML renderer.
- */
- static class Renderer extends View {
-
- Renderer(JComponent c, ViewFactory f, View v) {
- super(null);
- host = c;
- factory = f;
- view = v;
- view.setParent(this);
- // initially layout to the preferred size
- setSize(view.getPreferredSpan(X_AXIS), view.getPreferredSpan(Y_AXIS));
- }
-
- /**
- * Fetches the attributes to use when rendering. At the root
- * level there are no attributes. If an attribute is resolved
- * up the view hierarchy this is the end of the line.
- */
- public AttributeSet getAttributes() {
- return null;
- }
-
- /**
- * Determines the preferred span for this view along an axis.
- *
- * @param axis may be either X_AXIS or Y_AXIS
- * @return the span the view would like to be rendered into.
- * Typically the view is told to render into the span
- * that is returned, although there is no guarantee.
- * The parent may choose to resize or break the view.
- */
- public float getPreferredSpan(int axis) {
- if (axis == X_AXIS) {
- // width currently laid out to
- return width;
- }
- return view.getPreferredSpan(axis);
- }
-
- /**
- * Determines the minimum span for this view along an axis.
- *
- * @param axis may be either X_AXIS or Y_AXIS
- * @return the span the view would like to be rendered into.
- * Typically the view is told to render into the span
- * that is returned, although there is no guarantee.
- * The parent may choose to resize or break the view.
- */
- public float getMinimumSpan(int axis) {
- return view.getMinimumSpan(axis);
- }
-
- /**
- * Determines the maximum span for this view along an axis.
- *
- * @param axis may be either X_AXIS or Y_AXIS
- * @return the span the view would like to be rendered into.
- * Typically the view is told to render into the span
- * that is returned, although there is no guarantee.
- * The parent may choose to resize or break the view.
- */
- public float getMaximumSpan(int axis) {
- return Integer.MAX_VALUE;
- }
-
- /**
- * Specifies that a preference has changed.
- * Child views can call this on the parent to indicate that
- * the preference has changed. The root view routes this to
- * invalidate on the hosting component.
- * <p>
- * This can be called on a different thread from the
- * event dispatching thread and is basically unsafe to
- * propagate into the component. To make this safe,
- * the operation is transferred over to the event dispatching
- * thread for completion. It is a design goal that all view
- * methods be safe to call without concern for concurrency,
- * and this behavior helps make that true.
- *
- * @param child the child view
- * @param width true if the width preference has changed
- * @param height true if the height preference has changed
- */
- public void preferenceChanged(View child, boolean width, boolean height) {
- host.revalidate();
- }
-
- /**
- * Determines the desired alignment for this view along an axis.
- *
- * @param axis may be either X_AXIS or Y_AXIS
- * @return the desired alignment, where 0.0 indicates the origin
- * and 1.0 the full span away from the origin
- */
- public float getAlignment(int axis) {
- return view.getAlignment(axis);
- }
-
- /**
- * Renders the view.
- *
- * @param g the graphics context
- * @param allocation the region to render into
- */
- public void paint(Graphics g, Shape allocation) {
- Rectangle alloc = allocation.getBounds();
- view.setSize(alloc.width, alloc.height);
- view.paint(g, allocation);
- }
-
- /**
- * Sets the view parent.
- *
- * @param parent the parent view
- */
- public void setParent(View parent) {
- throw new Error("Can't set parent on root view");
- }
-
- /**
- * Returns the number of views in this view. Since
- * this view simply wraps the root of the view hierarchy
- * it has exactly one child.
- *
- * @return the number of views
- * @see #getView
- */
- public int getViewCount() {
- return 1;
- }
-
- /**
- * Gets the n-th view in this container.
- *
- * @param n the number of the view to get
- * @return the view
- */
- public View getView(int n) {
- return view;
- }
-
- /**
- * Provides a mapping from the document model coordinate space
- * to the coordinate space of the view mapped to it.
- *
- * @param pos the position to convert
- * @param a the allocated region to render into
- * @return the bounding box of the given position
- */
- public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException {
- return view.modelToView(pos, a, b);
- }
-
- /**
- * Provides a mapping from the document model coordinate space
- * to the coordinate space of the view mapped to it.
- *
- * @param p0 the position to convert >= 0
- * @param b0 the bias toward the previous character or the
- * next character represented by p0, in case the
- * position is a boundary of two views.
- * @param p1 the position to convert >= 0
- * @param b1 the bias toward the previous character or the
- * next character represented by p1, in case the
- * position is a boundary of two views.
- * @param a the allocated region to render into
- * @return the bounding box of the given position is returned
- * @exception BadLocationException if the given position does
- * not represent a valid location in the associated document
- * @exception IllegalArgumentException for an invalid bias argument
- * @see View#viewToModel
- */
- public Shape modelToView(int p0, Position.Bias b0, int p1,
- Position.Bias b1, Shape a) throws BadLocationException {
- return view.modelToView(p0, b0, p1, b1, a);
- }
-
- /**
- * Provides a mapping from the view coordinate space to the logical
- * coordinate space of the model.
- *
- * @param x x coordinate of the view location to convert
- * @param y y coordinate of the view location to convert
- * @param a the allocated region to render into
- * @return the location within the model that best represents the
- * given point in the view
- */
- public int viewToModel(float x, float y, Shape a, Position.Bias[] bias) {
- return view.viewToModel(x, y, a, bias);
- }
-
- /**
- * Returns the document model underlying the view.
- *
- * @return the model
- */
- public Document getDocument() {
- return view.getDocument();
- }
-
- /**
- * Returns the starting offset into the model for this view.
- *
- * @return the starting offset
- */
- public int getStartOffset() {
- return view.getStartOffset();
- }
-
- /**
- * Returns the ending offset into the model for this view.
- *
- * @return the ending offset
- */
- public int getEndOffset() {
- return view.getEndOffset();
- }
-
- /**
- * Gets the element that this view is mapped to.
- *
- * @return the view
- */
- public Element getElement() {
- return view.getElement();
- }
-
- /**
- * Sets the view size.
- *
- * @param width the width
- * @param height the height
- */
- public void setSize(float width, float height) {
- this.width = (int) width;
- view.setSize(width, height);
- }
-
- /**
- * Fetches the container hosting the view. This is useful for
- * things like scheduling a repaint, finding out the host
- * components font, etc. The default implementation
- * of this is to forward the query to the parent view.
- *
- * @return the container
- */
- public Container getContainer() {
- return host;
- }
-
- /**
- * Fetches the factory to be used for building the
- * various view fragments that make up the view that
- * represents the model. This is what determines
- * how the model will be represented. This is implemented
- * to fetch the factory provided by the associated
- * EditorKit.
- *
- * @return the factory
- */
- public ViewFactory getViewFactory() {
- return factory;
- }
-
- private int width;
- private View view;
- private ViewFactory factory;
- private JComponent host;
-
- }
- }