Java程序
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1333行
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48.21 KB
/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.text;
import android.annotation.UnsupportedAppUsage;
import android.app.ActivityThread;
import android.app.Application;
import android.content.res.Resources;
import android.graphics.Color;
import android.graphics.Typeface;
import android.graphics.drawable.Drawable;
import android.text.style.AbsoluteSizeSpan;
import android.text.style.AlignmentSpan;
import android.text.style.BackgroundColorSpan;
import android.text.style.BulletSpan;
import android.text.style.CharacterStyle;
import android.text.style.ForegroundColorSpan;
import android.text.style.ImageSpan;
import android.text.style.ParagraphStyle;
import android.text.style.QuoteSpan;
import android.text.style.RelativeSizeSpan;
import android.text.style.StrikethroughSpan;
import android.text.style.StyleSpan;
import android.text.style.SubscriptSpan;
import android.text.style.SuperscriptSpan;
import android.text.style.TypefaceSpan;
import android.text.style.URLSpan;
import android.text.style.UnderlineSpan;
import org.ccil.cowan.tagsoup.HTMLSchema;
import org.ccil.cowan.tagsoup.Parser;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import java.io.IOException;
import java.io.StringReader;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* This class processes HTML strings into displayable styled text.
* Not all HTML tags are supported.
*/
public class Html {
/**
* Retrieves images for HTML <img> tags.
*/
public static interface ImageGetter {
/**
* This method is called when the HTML parser encounters an
* <img> tag. The <code>source</code> argument is the
* string from the "src" attribute; the return value should be
* a Drawable representation of the image or <code>null</code>
* for a generic replacement image. Make sure you call
* setBounds() on your Drawable if it doesn't already have
* its bounds set.
*/
public Drawable getDrawable(String source);
}
/**
* Is notified when HTML tags are encountered that the parser does
* not know how to interpret.
*/
public static interface TagHandler {
/**
* This method will be called whenn the HTML parser encounters
* a tag that it does not know how to interpret.
*/
public void handleTag(boolean opening, String tag,
Editable output, XMLReader xmlReader);
}
/**
* Option for {@link #toHtml(Spanned, int)}: Wrap consecutive lines of text delimited by '\n'
* inside <p> elements. {@link BulletSpan}s are ignored.
*/
public static final int TO_HTML_PARAGRAPH_LINES_CONSECUTIVE = 0x00000000;
/**
* Option for {@link #toHtml(Spanned, int)}: Wrap each line of text delimited by '\n' inside a
* <p> or a <li> element. This allows {@link ParagraphStyle}s attached to be
* encoded as CSS styles within the corresponding <p> or <li> element.
*/
public static final int TO_HTML_PARAGRAPH_LINES_INDIVIDUAL = 0x00000001;
/**
* Flag indicating that texts inside <p> elements will be separated from other texts with
* one newline character by default.
*/
public static final int FROM_HTML_SEPARATOR_LINE_BREAK_PARAGRAPH = 0x00000001;
/**
* Flag indicating that texts inside <h1>~<h6> elements will be separated from
* other texts with one newline character by default.
*/
public static final int FROM_HTML_SEPARATOR_LINE_BREAK_HEADING = 0x00000002;
/**
* Flag indicating that texts inside <li> elements will be separated from other texts
* with one newline character by default.
*/
public static final int FROM_HTML_SEPARATOR_LINE_BREAK_LIST_ITEM = 0x00000004;
/**
* Flag indicating that texts inside <ul> elements will be separated from other texts
* with one newline character by default.
*/
public static final int FROM_HTML_SEPARATOR_LINE_BREAK_LIST = 0x00000008;
/**
* Flag indicating that texts inside <div> elements will be separated from other texts
* with one newline character by default.
*/
public static final int FROM_HTML_SEPARATOR_LINE_BREAK_DIV = 0x00000010;
/**
* Flag indicating that texts inside <blockquote> elements will be separated from other
* texts with one newline character by default.
*/
public static final int FROM_HTML_SEPARATOR_LINE_BREAK_BLOCKQUOTE = 0x00000020;
/**
* Flag indicating that CSS color values should be used instead of those defined in
* {@link Color}.
*/
public static final int FROM_HTML_OPTION_USE_CSS_COLORS = 0x00000100;
/**
* Flags for {@link #fromHtml(String, int, ImageGetter, TagHandler)}: Separate block-level
* elements with blank lines (two newline characters) in between. This is the legacy behavior
* prior to N.
*/
public static final int FROM_HTML_MODE_LEGACY = 0x00000000;
/**
* Flags for {@link #fromHtml(String, int, ImageGetter, TagHandler)}: Separate block-level
* elements with line breaks (single newline character) in between. This inverts the
* {@link Spanned} to HTML string conversion done with the option
* {@link #TO_HTML_PARAGRAPH_LINES_INDIVIDUAL}.
*/
public static final int FROM_HTML_MODE_COMPACT =
FROM_HTML_SEPARATOR_LINE_BREAK_PARAGRAPH
| FROM_HTML_SEPARATOR_LINE_BREAK_HEADING
| FROM_HTML_SEPARATOR_LINE_BREAK_LIST_ITEM
| FROM_HTML_SEPARATOR_LINE_BREAK_LIST
| FROM_HTML_SEPARATOR_LINE_BREAK_DIV
| FROM_HTML_SEPARATOR_LINE_BREAK_BLOCKQUOTE;
/**
* The bit which indicates if lines delimited by '\n' will be grouped into <p> elements.
*/
private static final int TO_HTML_PARAGRAPH_FLAG = 0x00000001;
private Html() { }
/**
* Returns displayable styled text from the provided HTML string with the legacy flags
* {@link #FROM_HTML_MODE_LEGACY}.
*
* @deprecated use {@link #fromHtml(String, int)} instead.
*/
@Deprecated
public static Spanned fromHtml(String source) {
return fromHtml(source, FROM_HTML_MODE_LEGACY, null, null);
}
/**
* Returns displayable styled text from the provided HTML string. Any <img> tags in the
* HTML will display as a generic replacement image which your program can then go through and
* replace with real images.
*
* <p>This uses TagSoup to handle real HTML, including all of the brokenness found in the wild.
*/
public static Spanned fromHtml(String source, int flags) {
return fromHtml(source, flags, null, null);
}
/**
* Lazy initialization holder for HTML parser. This class will
* a) be preloaded by the zygote, or b) not loaded until absolutely
* necessary.
*/
private static class HtmlParser {
private static final HTMLSchema schema = new HTMLSchema();
}
/**
* Returns displayable styled text from the provided HTML string with the legacy flags
* {@link #FROM_HTML_MODE_LEGACY}.
*
* @deprecated use {@link #fromHtml(String, int, ImageGetter, TagHandler)} instead.
*/
@Deprecated
public static Spanned fromHtml(String source, ImageGetter imageGetter, TagHandler tagHandler) {
return fromHtml(source, FROM_HTML_MODE_LEGACY, imageGetter, tagHandler);
}
/**
* Returns displayable styled text from the provided HTML string. Any <img> tags in the
* HTML will use the specified ImageGetter to request a representation of the image (use null
* if you don't want this) and the specified TagHandler to handle unknown tags (specify null if
* you don't want this).
*
* <p>This uses TagSoup to handle real HTML, including all of the brokenness found in the wild.
*/
public static Spanned fromHtml(String source, int flags, ImageGetter imageGetter,
TagHandler tagHandler) {
Parser parser = new Parser();
try {
parser.setProperty(Parser.schemaProperty, HtmlParser.schema);
} catch (org.xml.sax.SAXNotRecognizedException e) {
// Should not happen.
throw new RuntimeException(e);
} catch (org.xml.sax.SAXNotSupportedException e) {
// Should not happen.
throw new RuntimeException(e);
}
HtmlToSpannedConverter converter =
new HtmlToSpannedConverter(source, imageGetter, tagHandler, parser, flags);
return converter.convert();
}
/**
* @deprecated use {@link #toHtml(Spanned, int)} instead.
*/
@Deprecated
public static String toHtml(Spanned text) {
return toHtml(text, TO_HTML_PARAGRAPH_LINES_CONSECUTIVE);
}
/**
* Returns an HTML representation of the provided Spanned text. A best effort is
* made to add HTML tags corresponding to spans. Also note that HTML metacharacters
* (such as "<" and "&") within the input text are escaped.
*
* @param text input text to convert
* @param option one of {@link #TO_HTML_PARAGRAPH_LINES_CONSECUTIVE} or
* {@link #TO_HTML_PARAGRAPH_LINES_INDIVIDUAL}
* @return string containing input converted to HTML
*/
public static String toHtml(Spanned text, int option) {
StringBuilder out = new StringBuilder();
withinHtml(out, text, option);
return out.toString();
}
/**
* Returns an HTML escaped representation of the given plain text.
*/
public static String escapeHtml(CharSequence text) {
StringBuilder out = new StringBuilder();
withinStyle(out, text, 0, text.length());
return out.toString();
}
private static void withinHtml(StringBuilder out, Spanned text, int option) {
if ((option & TO_HTML_PARAGRAPH_FLAG) == TO_HTML_PARAGRAPH_LINES_CONSECUTIVE) {
encodeTextAlignmentByDiv(out, text, option);
return;
}
withinDiv(out, text, 0, text.length(), option);
}
private static void encodeTextAlignmentByDiv(StringBuilder out, Spanned text, int option) {
int len = text.length();
int next;
for (int i = 0; i < len; i = next) {
next = text.nextSpanTransition(i, len, ParagraphStyle.class);
ParagraphStyle[] style = text.getSpans(i, next, ParagraphStyle.class);
String elements = " ";
boolean needDiv = false;
for(int j = 0; j < style.length; j++) {
if (style[j] instanceof AlignmentSpan) {
Layout.Alignment align =
((AlignmentSpan) style[j]).getAlignment();
needDiv = true;
if (align == Layout.Alignment.ALIGN_CENTER) {
elements = "align=\"center\" " + elements;
} else if (align == Layout.Alignment.ALIGN_OPPOSITE) {
elements = "align=\"right\" " + elements;
} else {
elements = "align=\"left\" " + elements;
}
}
}
if (needDiv) {
out.append("<div ").append(elements).append(">");
}
withinDiv(out, text, i, next, option);
if (needDiv) {
out.append("</div>");
}
}
}
private static void withinDiv(StringBuilder out, Spanned text, int start, int end,
int option) {
int next;
for (int i = start; i < end; i = next) {
next = text.nextSpanTransition(i, end, QuoteSpan.class);
QuoteSpan[] quotes = text.getSpans(i, next, QuoteSpan.class);
for (QuoteSpan quote : quotes) {
out.append("<blockquote>");
}
withinBlockquote(out, text, i, next, option);
for (QuoteSpan quote : quotes) {
out.append("</blockquote>\n");
}
}
}
private static String getTextDirection(Spanned text, int start, int end) {
if (TextDirectionHeuristics.FIRSTSTRONG_LTR.isRtl(text, start, end - start)) {
return " dir=\"rtl\"";
} else {
return " dir=\"ltr\"";
}
}
private static String getTextStyles(Spanned text, int start, int end,
boolean forceNoVerticalMargin, boolean includeTextAlign) {
String margin = null;
String textAlign = null;
if (forceNoVerticalMargin) {
margin = "margin-top:0; margin-bottom:0;";
}
if (includeTextAlign) {
final AlignmentSpan[] alignmentSpans = text.getSpans(start, end, AlignmentSpan.class);
// Only use the last AlignmentSpan with flag SPAN_PARAGRAPH
for (int i = alignmentSpans.length - 1; i >= 0; i--) {
AlignmentSpan s = alignmentSpans[i];
if ((text.getSpanFlags(s) & Spanned.SPAN_PARAGRAPH) == Spanned.SPAN_PARAGRAPH) {
final Layout.Alignment alignment = s.getAlignment();
if (alignment == Layout.Alignment.ALIGN_NORMAL) {
textAlign = "text-align:start;";
} else if (alignment == Layout.Alignment.ALIGN_CENTER) {
textAlign = "text-align:center;";
} else if (alignment == Layout.Alignment.ALIGN_OPPOSITE) {
textAlign = "text-align:end;";
}
break;
}
}
}
if (margin == null && textAlign == null) {
return "";
}
final StringBuilder style = new StringBuilder(" style=\"");
if (margin != null && textAlign != null) {
style.append(margin).append(" ").append(textAlign);
} else if (margin != null) {
style.append(margin);
} else if (textAlign != null) {
style.append(textAlign);
}
return style.append("\"").toString();
}
private static void withinBlockquote(StringBuilder out, Spanned text, int start, int end,
int option) {
if ((option & TO_HTML_PARAGRAPH_FLAG) == TO_HTML_PARAGRAPH_LINES_CONSECUTIVE) {
withinBlockquoteConsecutive(out, text, start, end);
} else {
withinBlockquoteIndividual(out, text, start, end);
}
}
private static void withinBlockquoteIndividual(StringBuilder out, Spanned text, int start,
int end) {
boolean isInList = false;
int next;
for (int i = start; i <= end; i = next) {
next = TextUtils.indexOf(text, '\n', i, end);
if (next < 0) {
next = end;
}
if (next == i) {
if (isInList) {
// Current paragraph is no longer a list item; close the previously opened list
isInList = false;
out.append("</ul>\n");
}
out.append("<br>\n");
} else {
boolean isListItem = false;
ParagraphStyle[] paragraphStyles = text.getSpans(i, next, ParagraphStyle.class);
for (ParagraphStyle paragraphStyle : paragraphStyles) {
final int spanFlags = text.getSpanFlags(paragraphStyle);
if ((spanFlags & Spanned.SPAN_PARAGRAPH) == Spanned.SPAN_PARAGRAPH
&& paragraphStyle instanceof BulletSpan) {
isListItem = true;
break;
}
}
if (isListItem && !isInList) {
// Current paragraph is the first item in a list
isInList = true;
out.append("<ul")
.append(getTextStyles(text, i, next, true, false))
.append(">\n");
}
if (isInList && !isListItem) {
// Current paragraph is no longer a list item; close the previously opened list
isInList = false;
out.append("</ul>\n");
}
String tagType = isListItem ? "li" : "p";
out.append("<").append(tagType)
.append(getTextDirection(text, i, next))
.append(getTextStyles(text, i, next, !isListItem, true))
.append(">");
withinParagraph(out, text, i, next);
out.append("</");
out.append(tagType);
out.append(">\n");
if (next == end && isInList) {
isInList = false;
out.append("</ul>\n");
}
}
next++;
}
}
private static void withinBlockquoteConsecutive(StringBuilder out, Spanned text, int start,
int end) {
out.append("<p").append(getTextDirection(text, start, end)).append(">");
int next;
for (int i = start; i < end; i = next) {
next = TextUtils.indexOf(text, '\n', i, end);
if (next < 0) {
next = end;
}
int nl = 0;
while (next < end && text.charAt(next) == '\n') {
nl++;
next++;
}
withinParagraph(out, text, i, next - nl);
if (nl == 1) {
out.append("<br>\n");
} else {
for (int j = 2; j < nl; j++) {
out.append("<br>");
}
if (next != end) {
/* Paragraph should be closed and reopened */
out.append("</p>\n");
out.append("<p").append(getTextDirection(text, start, end)).append(">");
}
}
}
out.append("</p>\n");
}
private static void withinParagraph(StringBuilder out, Spanned text, int start, int end) {
int next;
for (int i = start; i < end; i = next) {
next = text.nextSpanTransition(i, end, CharacterStyle.class);
CharacterStyle[] style = text.getSpans(i, next, CharacterStyle.class);
for (int j = 0; j < style.length; j++) {
if (style[j] instanceof StyleSpan) {
int s = ((StyleSpan) style[j]).getStyle();
if ((s & Typeface.BOLD) != 0) {
out.append("<b>");
}
if ((s & Typeface.ITALIC) != 0) {
out.append("<i>");
}
}
if (style[j] instanceof TypefaceSpan) {
String s = ((TypefaceSpan) style[j]).getFamily();
if ("monospace".equals(s)) {
out.append("<tt>");
}
}
if (style[j] instanceof SuperscriptSpan) {
out.append("<sup>");
}
if (style[j] instanceof SubscriptSpan) {
out.append("<sub>");
}
if (style[j] instanceof UnderlineSpan) {
out.append("<u>");
}
if (style[j] instanceof StrikethroughSpan) {
out.append("<span style=\"text-decoration:line-through;\">");
}
if (style[j] instanceof URLSpan) {
out.append("<a href=\"");
out.append(((URLSpan) style[j]).getURL());
out.append("\">");
}
if (style[j] instanceof ImageSpan) {
out.append("<img src=\"");
out.append(((ImageSpan) style[j]).getSource());
out.append("\">");
// Don't output the dummy character underlying the image.
i = next;
}
if (style[j] instanceof AbsoluteSizeSpan) {
AbsoluteSizeSpan s = ((AbsoluteSizeSpan) style[j]);
float sizeDip = s.getSize();
if (!s.getDip()) {
Application application = ActivityThread.currentApplication();
sizeDip /= application.getResources().getDisplayMetrics().density;
}
// px in CSS is the equivalance of dip in Android
out.append(String.format("<span style=\"font-size:%.0fpx\";>", sizeDip));
}
if (style[j] instanceof RelativeSizeSpan) {
float sizeEm = ((RelativeSizeSpan) style[j]).getSizeChange();
out.append(String.format("<span style=\"font-size:%.2fem;\">", sizeEm));
}
if (style[j] instanceof ForegroundColorSpan) {
int color = ((ForegroundColorSpan) style[j]).getForegroundColor();
out.append(String.format("<span style=\"color:#%06X;\">", 0xFFFFFF & color));
}
if (style[j] instanceof BackgroundColorSpan) {
int color = ((BackgroundColorSpan) style[j]).getBackgroundColor();
out.append(String.format("<span style=\"background-color:#%06X;\">",
0xFFFFFF & color));
}
}
withinStyle(out, text, i, next);
for (int j = style.length - 1; j >= 0; j--) {
if (style[j] instanceof BackgroundColorSpan) {
out.append("</span>");
}
if (style[j] instanceof ForegroundColorSpan) {
out.append("</span>");
}
if (style[j] instanceof RelativeSizeSpan) {
out.append("</span>");
}
if (style[j] instanceof AbsoluteSizeSpan) {
out.append("</span>");
}
if (style[j] instanceof URLSpan) {
out.append("</a>");
}
if (style[j] instanceof StrikethroughSpan) {
out.append("</span>");
}
if (style[j] instanceof UnderlineSpan) {
out.append("</u>");
}
if (style[j] instanceof SubscriptSpan) {
out.append("</sub>");
}
if (style[j] instanceof SuperscriptSpan) {
out.append("</sup>");
}
if (style[j] instanceof TypefaceSpan) {
String s = ((TypefaceSpan) style[j]).getFamily();
if (s.equals("monospace")) {
out.append("</tt>");
}
}
if (style[j] instanceof StyleSpan) {
int s = ((StyleSpan) style[j]).getStyle();
if ((s & Typeface.BOLD) != 0) {
out.append("</b>");
}
if ((s & Typeface.ITALIC) != 0) {
out.append("</i>");
}
}
}
}
}
@UnsupportedAppUsage
private static void withinStyle(StringBuilder out, CharSequence text,
int start, int end) {
for (int i = start; i < end; i++) {
char c = text.charAt(i);
if (c == '<') {
out.append("<");
} else if (c == '>') {
out.append(">");
} else if (c == '&') {
out.append("&");
} else if (c >= 0xD800 && c <= 0xDFFF) {
if (c < 0xDC00 && i + 1 < end) {
char d = text.charAt(i + 1);
if (d >= 0xDC00 && d <= 0xDFFF) {
i++;
int codepoint = 0x010000 | (int) c - 0xD800 << 10 | (int) d - 0xDC00;
out.append("&#").append(codepoint).append(";");
}
}
} else if (c > 0x7E || c < ' ') {
out.append("&#").append((int) c).append(";");
} else if (c == ' ') {
while (i + 1 < end && text.charAt(i + 1) == ' ') {
out.append(" ");
i++;
}
out.append(' ');
} else {
out.append(c);
}
}
}
}
class HtmlToSpannedConverter implements ContentHandler {
private static final float[] HEADING_SIZES = {
1.5f, 1.4f, 1.3f, 1.2f, 1.1f, 1f,
};
private String mSource;
private XMLReader mReader;
private SpannableStringBuilder mSpannableStringBuilder;
private Html.ImageGetter mImageGetter;
private Html.TagHandler mTagHandler;
private int mFlags;
private static Pattern sTextAlignPattern;
private static Pattern sForegroundColorPattern;
private static Pattern sBackgroundColorPattern;
private static Pattern sTextDecorationPattern;
/**
* Name-value mapping of HTML/CSS colors which have different values in {@link Color}.
*/
private static final Map<String, Integer> sColorMap;
static {
sColorMap = new HashMap<>();
sColorMap.put("darkgray", 0xFFA9A9A9);
sColorMap.put("gray", 0xFF808080);
sColorMap.put("lightgray", 0xFFD3D3D3);
sColorMap.put("darkgrey", 0xFFA9A9A9);
sColorMap.put("grey", 0xFF808080);
sColorMap.put("lightgrey", 0xFFD3D3D3);
sColorMap.put("green", 0xFF008000);
}
private static Pattern getTextAlignPattern() {
if (sTextAlignPattern == null) {
sTextAlignPattern = Pattern.compile("(?:\\s+|\\A)text-align\\s*:\\s*(\\S*)\\b");
}
return sTextAlignPattern;
}
private static Pattern getForegroundColorPattern() {
if (sForegroundColorPattern == null) {
sForegroundColorPattern = Pattern.compile(
"(?:\\s+|\\A)color\\s*:\\s*(\\S*)\\b");
}
return sForegroundColorPattern;
}
private static Pattern getBackgroundColorPattern() {
if (sBackgroundColorPattern == null) {
sBackgroundColorPattern = Pattern.compile(
"(?:\\s+|\\A)background(?:-color)?\\s*:\\s*(\\S*)\\b");
}
return sBackgroundColorPattern;
}
private static Pattern getTextDecorationPattern() {
if (sTextDecorationPattern == null) {
sTextDecorationPattern = Pattern.compile(
"(?:\\s+|\\A)text-decoration\\s*:\\s*(\\S*)\\b");
}
return sTextDecorationPattern;
}
public HtmlToSpannedConverter( String source, Html.ImageGetter imageGetter,
Html.TagHandler tagHandler, Parser parser, int flags) {
mSource = source;
mSpannableStringBuilder = new SpannableStringBuilder();
mImageGetter = imageGetter;
mTagHandler = tagHandler;
mReader = parser;
mFlags = flags;
}
public Spanned convert() {
mReader.setContentHandler(this);
try {
mReader.parse(new InputSource(new StringReader(mSource)));
} catch (IOException e) {
// We are reading from a string. There should not be IO problems.
throw new RuntimeException(e);
} catch (SAXException e) {
// TagSoup doesn't throw parse exceptions.
throw new RuntimeException(e);
}
// Fix flags and range for paragraph-type markup.
Object[] obj = mSpannableStringBuilder.getSpans(0, mSpannableStringBuilder.length(), ParagraphStyle.class);
for (int i = 0; i < obj.length; i++) {
int start = mSpannableStringBuilder.getSpanStart(obj[i]);
int end = mSpannableStringBuilder.getSpanEnd(obj[i]);
// If the last line of the range is blank, back off by one.
if (end - 2 >= 0) {
if (mSpannableStringBuilder.charAt(end - 1) == '\n' &&
mSpannableStringBuilder.charAt(end - 2) == '\n') {
end--;
}
}
if (end == start) {
mSpannableStringBuilder.removeSpan(obj[i]);
} else {
mSpannableStringBuilder.setSpan(obj[i], start, end, Spannable.SPAN_PARAGRAPH);
}
}
return mSpannableStringBuilder;
}
private void handleStartTag(String tag, Attributes attributes) {
if (tag.equalsIgnoreCase("br")) {
// We don't need to handle this. TagSoup will ensure that there's a </br> for each <br>
// so we can safely emit the linebreaks when we handle the close tag.
} else if (tag.equalsIgnoreCase("p")) {
startBlockElement(mSpannableStringBuilder, attributes, getMarginParagraph());
startCssStyle(mSpannableStringBuilder, attributes);
} else if (tag.equalsIgnoreCase("ul")) {
startBlockElement(mSpannableStringBuilder, attributes, getMarginList());
} else if (tag.equalsIgnoreCase("li")) {
startLi(mSpannableStringBuilder, attributes);
} else if (tag.equalsIgnoreCase("div")) {
startBlockElement(mSpannableStringBuilder, attributes, getMarginDiv());
} else if (tag.equalsIgnoreCase("span")) {
startCssStyle(mSpannableStringBuilder, attributes);
} else if (tag.equalsIgnoreCase("strong")) {
start(mSpannableStringBuilder, new Bold());
} else if (tag.equalsIgnoreCase("b")) {
start(mSpannableStringBuilder, new Bold());
} else if (tag.equalsIgnoreCase("em")) {
start(mSpannableStringBuilder, new Italic());
} else if (tag.equalsIgnoreCase("cite")) {
start(mSpannableStringBuilder, new Italic());
} else if (tag.equalsIgnoreCase("dfn")) {
start(mSpannableStringBuilder, new Italic());
} else if (tag.equalsIgnoreCase("i")) {
start(mSpannableStringBuilder, new Italic());
} else if (tag.equalsIgnoreCase("big")) {
start(mSpannableStringBuilder, new Big());
} else if (tag.equalsIgnoreCase("small")) {
start(mSpannableStringBuilder, new Small());
} else if (tag.equalsIgnoreCase("font")) {
startFont(mSpannableStringBuilder, attributes);
} else if (tag.equalsIgnoreCase("blockquote")) {
startBlockquote(mSpannableStringBuilder, attributes);
} else if (tag.equalsIgnoreCase("tt")) {
start(mSpannableStringBuilder, new Monospace());
} else if (tag.equalsIgnoreCase("a")) {
startA(mSpannableStringBuilder, attributes);
} else if (tag.equalsIgnoreCase("u")) {
start(mSpannableStringBuilder, new Underline());
} else if (tag.equalsIgnoreCase("del")) {
start(mSpannableStringBuilder, new Strikethrough());
} else if (tag.equalsIgnoreCase("s")) {
start(mSpannableStringBuilder, new Strikethrough());
} else if (tag.equalsIgnoreCase("strike")) {
start(mSpannableStringBuilder, new Strikethrough());
} else if (tag.equalsIgnoreCase("sup")) {
start(mSpannableStringBuilder, new Super());
} else if (tag.equalsIgnoreCase("sub")) {
start(mSpannableStringBuilder, new Sub());
} else if (tag.length() == 2 &&
Character.toLowerCase(tag.charAt(0)) == 'h' &&
tag.charAt(1) >= '1' && tag.charAt(1) <= '6') {
startHeading(mSpannableStringBuilder, attributes, tag.charAt(1) - '1');
} else if (tag.equalsIgnoreCase("img")) {
startImg(mSpannableStringBuilder, attributes, mImageGetter);
} else if (mTagHandler != null) {
mTagHandler.handleTag(true, tag, mSpannableStringBuilder, mReader);
}
}
private void handleEndTag(String tag) {
if (tag.equalsIgnoreCase("br")) {
handleBr(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("p")) {
endCssStyle(mSpannableStringBuilder);
endBlockElement(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("ul")) {
endBlockElement(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("li")) {
endLi(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("div")) {
endBlockElement(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("span")) {
endCssStyle(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("strong")) {
end(mSpannableStringBuilder, Bold.class, new StyleSpan(Typeface.BOLD));
} else if (tag.equalsIgnoreCase("b")) {
end(mSpannableStringBuilder, Bold.class, new StyleSpan(Typeface.BOLD));
} else if (tag.equalsIgnoreCase("em")) {
end(mSpannableStringBuilder, Italic.class, new StyleSpan(Typeface.ITALIC));
} else if (tag.equalsIgnoreCase("cite")) {
end(mSpannableStringBuilder, Italic.class, new StyleSpan(Typeface.ITALIC));
} else if (tag.equalsIgnoreCase("dfn")) {
end(mSpannableStringBuilder, Italic.class, new StyleSpan(Typeface.ITALIC));
} else if (tag.equalsIgnoreCase("i")) {
end(mSpannableStringBuilder, Italic.class, new StyleSpan(Typeface.ITALIC));
} else if (tag.equalsIgnoreCase("big")) {
end(mSpannableStringBuilder, Big.class, new RelativeSizeSpan(1.25f));
} else if (tag.equalsIgnoreCase("small")) {
end(mSpannableStringBuilder, Small.class, new RelativeSizeSpan(0.8f));
} else if (tag.equalsIgnoreCase("font")) {
endFont(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("blockquote")) {
endBlockquote(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("tt")) {
end(mSpannableStringBuilder, Monospace.class, new TypefaceSpan("monospace"));
} else if (tag.equalsIgnoreCase("a")) {
endA(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("u")) {
end(mSpannableStringBuilder, Underline.class, new UnderlineSpan());
} else if (tag.equalsIgnoreCase("del")) {
end(mSpannableStringBuilder, Strikethrough.class, new StrikethroughSpan());
} else if (tag.equalsIgnoreCase("s")) {
end(mSpannableStringBuilder, Strikethrough.class, new StrikethroughSpan());
} else if (tag.equalsIgnoreCase("strike")) {
end(mSpannableStringBuilder, Strikethrough.class, new StrikethroughSpan());
} else if (tag.equalsIgnoreCase("sup")) {
end(mSpannableStringBuilder, Super.class, new SuperscriptSpan());
} else if (tag.equalsIgnoreCase("sub")) {
end(mSpannableStringBuilder, Sub.class, new SubscriptSpan());
} else if (tag.length() == 2 &&
Character.toLowerCase(tag.charAt(0)) == 'h' &&
tag.charAt(1) >= '1' && tag.charAt(1) <= '6') {
endHeading(mSpannableStringBuilder);
} else if (mTagHandler != null) {
mTagHandler.handleTag(false, tag, mSpannableStringBuilder, mReader);
}
}
private int getMarginParagraph() {
return getMargin(Html.FROM_HTML_SEPARATOR_LINE_BREAK_PARAGRAPH);
}
private int getMarginHeading() {
return getMargin(Html.FROM_HTML_SEPARATOR_LINE_BREAK_HEADING);
}
private int getMarginListItem() {
return getMargin(Html.FROM_HTML_SEPARATOR_LINE_BREAK_LIST_ITEM);
}
private int getMarginList() {
return getMargin(Html.FROM_HTML_SEPARATOR_LINE_BREAK_LIST);
}
private int getMarginDiv() {
return getMargin(Html.FROM_HTML_SEPARATOR_LINE_BREAK_DIV);
}
private int getMarginBlockquote() {
return getMargin(Html.FROM_HTML_SEPARATOR_LINE_BREAK_BLOCKQUOTE);
}
/**
* Returns the minimum number of newline characters needed before and after a given block-level
* element.
*
* @param flag the corresponding option flag defined in {@link Html} of a block-level element
*/
private int getMargin(int flag) {
if ((flag & mFlags) != 0) {
return 1;
}
return 2;
}
private static void appendNewlines(Editable text, int minNewline) {
final int len = text.length();
if (len == 0) {
return;
}
int existingNewlines = 0;
for (int i = len - 1; i >= 0 && text.charAt(i) == '\n'; i--) {
existingNewlines++;
}
for (int j = existingNewlines; j < minNewline; j++) {
text.append("\n");
}
}
private static void startBlockElement(Editable text, Attributes attributes, int margin) {
final int len = text.length();
if (margin > 0) {
appendNewlines(text, margin);
start(text, new Newline(margin));
}
String style = attributes.getValue("", "style");
if (style != null) {
Matcher m = getTextAlignPattern().matcher(style);
if (m.find()) {
String alignment = m.group(1);
if (alignment.equalsIgnoreCase("start")) {
start(text, new Alignment(Layout.Alignment.ALIGN_NORMAL));
} else if (alignment.equalsIgnoreCase("center")) {
start(text, new Alignment(Layout.Alignment.ALIGN_CENTER));
} else if (alignment.equalsIgnoreCase("end")) {
start(text, new Alignment(Layout.Alignment.ALIGN_OPPOSITE));
}
}
}
}
private static void endBlockElement(Editable text) {
Newline n = getLast(text, Newline.class);
if (n != null) {
appendNewlines(text, n.mNumNewlines);
text.removeSpan(n);
}
Alignment a = getLast(text, Alignment.class);
if (a != null) {
setSpanFromMark(text, a, new AlignmentSpan.Standard(a.mAlignment));
}
}
private static void handleBr(Editable text) {
text.append('\n');
}
private void startLi(Editable text, Attributes attributes) {
startBlockElement(text, attributes, getMarginListItem());
start(text, new Bullet());
startCssStyle(text, attributes);
}
private static void endLi(Editable text) {
endCssStyle(text);
endBlockElement(text);
end(text, Bullet.class, new BulletSpan());
}
private void startBlockquote(Editable text, Attributes attributes) {
startBlockElement(text, attributes, getMarginBlockquote());
start(text, new Blockquote());
}
private static void endBlockquote(Editable text) {
endBlockElement(text);
end(text, Blockquote.class, new QuoteSpan());
}
private void startHeading(Editable text, Attributes attributes, int level) {
startBlockElement(text, attributes, getMarginHeading());
start(text, new Heading(level));
}
private static void endHeading(Editable text) {
// RelativeSizeSpan and StyleSpan are CharacterStyles
// Their ranges should not include the newlines at the end
Heading h = getLast(text, Heading.class);
if (h != null) {
setSpanFromMark(text, h, new RelativeSizeSpan(HEADING_SIZES[h.mLevel]),
new StyleSpan(Typeface.BOLD));
}
endBlockElement(text);
}
private static <T> T getLast(Spanned text, Class<T> kind) {
/*
* This knows that the last returned object from getSpans()
* will be the most recently added.
*/
T[] objs = text.getSpans(0, text.length(), kind);
if (objs.length == 0) {
return null;
} else {
return objs[objs.length - 1];
}
}
private static void setSpanFromMark(Spannable text, Object mark, Object... spans) {
int where = text.getSpanStart(mark);
text.removeSpan(mark);
int len = text.length();
if (where != len) {
for (Object span : spans) {
text.setSpan(span, where, len, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
}
}
}
private static void start(Editable text, Object mark) {
int len = text.length();
text.setSpan(mark, len, len, Spannable.SPAN_INCLUSIVE_EXCLUSIVE);
}
private static void end(Editable text, Class kind, Object repl) {
int len = text.length();
Object obj = getLast(text, kind);
if (obj != null) {
setSpanFromMark(text, obj, repl);
}
}
private void startCssStyle(Editable text, Attributes attributes) {
String style = attributes.getValue("", "style");
if (style != null) {
Matcher m = getForegroundColorPattern().matcher(style);
if (m.find()) {
int c = getHtmlColor(m.group(1));
if (c != -1) {
start(text, new Foreground(c | 0xFF000000));
}
}
m = getBackgroundColorPattern().matcher(style);
if (m.find()) {
int c = getHtmlColor(m.group(1));
if (c != -1) {
start(text, new Background(c | 0xFF000000));
}
}
m = getTextDecorationPattern().matcher(style);
if (m.find()) {
String textDecoration = m.group(1);
if (textDecoration.equalsIgnoreCase("line-through")) {
start(text, new Strikethrough());
}
}
}
}
private static void endCssStyle(Editable text) {
Strikethrough s = getLast(text, Strikethrough.class);
if (s != null) {
setSpanFromMark(text, s, new StrikethroughSpan());
}
Background b = getLast(text, Background.class);
if (b != null) {
setSpanFromMark(text, b, new BackgroundColorSpan(b.mBackgroundColor));
}
Foreground f = getLast(text, Foreground.class);
if (f != null) {
setSpanFromMark(text, f, new ForegroundColorSpan(f.mForegroundColor));
}
}
private static void startImg(Editable text, Attributes attributes, Html.ImageGetter img) {
String src = attributes.getValue("", "src");
Drawable d = null;
if (img != null) {
d = img.getDrawable(src);
}
if (d == null) {
d = Resources.getSystem().
getDrawable(com.android.internal.R.drawable.unknown_image);
d.setBounds(0, 0, d.getIntrinsicWidth(), d.getIntrinsicHeight());
}
int len = text.length();
text.append("\uFFFC");
text.setSpan(new ImageSpan(d, src), len, text.length(),
Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
}
private void startFont(Editable text, Attributes attributes) {
String color = attributes.getValue("", "color");
String face = attributes.getValue("", "face");
if (!TextUtils.isEmpty(color)) {
int c = getHtmlColor(color);
if (c != -1) {
start(text, new Foreground(c | 0xFF000000));
}
}
if (!TextUtils.isEmpty(face)) {
start(text, new Font(face));
}
}
private static void endFont(Editable text) {
Font font = getLast(text, Font.class);
if (font != null) {
setSpanFromMark(text, font, new TypefaceSpan(font.mFace));
}
Foreground foreground = getLast(text, Foreground.class);
if (foreground != null) {
setSpanFromMark(text, foreground,
new ForegroundColorSpan(foreground.mForegroundColor));
}
}
private static void startA(Editable text, Attributes attributes) {
String href = attributes.getValue("", "href");
start(text, new Href(href));
}
private static void endA(Editable text) {
Href h = getLast(text, Href.class);
if (h != null) {
if (h.mHref != null) {
setSpanFromMark(text, h, new URLSpan((h.mHref)));
}
}
}
private int getHtmlColor(String color) {
if ((mFlags & Html.FROM_HTML_OPTION_USE_CSS_COLORS)
== Html.FROM_HTML_OPTION_USE_CSS_COLORS) {
Integer i = sColorMap.get(color.toLowerCase(Locale.US));
if (i != null) {
return i;
}
}
return Color.getHtmlColor(color);
}
public void setDocumentLocator(Locator locator) {
}
public void startDocument() throws SAXException {
}
public void endDocument() throws SAXException {
}
public void startPrefixMapping(String prefix, String uri) throws SAXException {
}
public void endPrefixMapping(String prefix) throws SAXException {
}
public void startElement(String uri, String localName, String qName, Attributes attributes)
throws SAXException {
handleStartTag(localName, attributes);
}
public void endElement(String uri, String localName, String qName) throws SAXException {
handleEndTag(localName);
}
public void characters(char ch[], int start, int length) throws SAXException {
StringBuilder sb = new StringBuilder();
/*
* Ignore whitespace that immediately follows other whitespace;
* newlines count as spaces.
*/
for (int i = 0; i < length; i++) {
char c = ch[i + start];
if (c == ' ' || c == '\n') {
char pred;
int len = sb.length();
if (len == 0) {
len = mSpannableStringBuilder.length();
if (len == 0) {
pred = '\n';
} else {
pred = mSpannableStringBuilder.charAt(len - 1);
}
} else {
pred = sb.charAt(len - 1);
}
if (pred != ' ' && pred != '\n') {
sb.append(' ');
}
} else {
sb.append(c);
}
}
mSpannableStringBuilder.append(sb);
}
public void ignorableWhitespace(char ch[], int start, int length) throws SAXException {
}
public void processingInstruction(String target, String data) throws SAXException {
}
public void skippedEntity(String name) throws SAXException {
}
private static class Bold { }
private static class Italic { }
private static class Underline { }
private static class Strikethrough { }
private static class Big { }
private static class Small { }
private static class Monospace { }
private static class Blockquote { }
private static class Super { }
private static class Sub { }
private static class Bullet { }
private static class Font {
public String mFace;
public Font(String face) {
mFace = face;
}
}
private static class Href {
public String mHref;
public Href(String href) {
mHref = href;
}
}
private static class Foreground {
private int mForegroundColor;
public Foreground(int foregroundColor) {
mForegroundColor = foregroundColor;
}
}
private static class Background {
private int mBackgroundColor;
public Background(int backgroundColor) {
mBackgroundColor = backgroundColor;
}
}
private static class Heading {
private int mLevel;
public Heading(int level) {
mLevel = level;
}
}
private static class Newline {
private int mNumNewlines;
public Newline(int numNewlines) {
mNumNewlines = numNewlines;
}
}
private static class Alignment {
private Layout.Alignment mAlignment;
public Alignment(Layout.Alignment alignment) {
mAlignment = alignment;
}
}
}