Java tutorial
/* * 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 com.zulip.android.util; import android.content.Context; import android.content.res.ColorStateList; import android.content.res.Resources; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Typeface; import android.graphics.drawable.Drawable; import android.support.annotation.NonNull; import android.support.v4.content.ContextCompat; import android.text.Html; import android.text.Layout; import android.text.Spannable; import android.text.SpannableStringBuilder; import android.text.Spanned; import android.text.TextUtils; 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.StyleSpan; import android.text.style.SubscriptSpan; import android.text.style.SuperscriptSpan; import android.text.style.TextAppearanceSpan; import android.text.style.TypefaceSpan; import android.text.style.URLSpan; import android.text.style.UnderlineSpan; import android.text.util.Linkify; import android.util.Pair; import com.zulip.android.R; import com.zulip.android.ZulipApp; 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.ArrayList; import java.util.HashMap; import java.util.List; public class CustomHtmlToSpannedConverter implements ContentHandler { private static final float[] HEADER_SIZES = { 1.5f, 1.4f, 1.3f, 1.2f, 1.1f, 1f, }; private static final String MONOSPACE = "monospace"; private static HashMap<String, Integer> COLORS = buildColorMap(); private String mSource; private XMLReader mReader; private SpannableStringBuilder mSpannableStringBuilder; private Html.ImageGetter mImageGetter; private Html.TagHandler mTagHandler; private Html.ImageGetter mEmojiGetter; private String mBaseUri; private static int userMentionColor; private static int userMentionSelfColor; public CustomHtmlToSpannedConverter(String source, Html.ImageGetter imageGetter, Html.TagHandler tagHandler, Parser parser, Html.ImageGetter emojiGetter, String baseUri, Context context) { mSource = source; mSpannableStringBuilder = new SpannableStringBuilder(); mImageGetter = imageGetter; mTagHandler = tagHandler; mReader = parser; mEmojiGetter = emojiGetter; mBaseUri = baseUri; userMentionColor = ContextCompat.getColor(context, R.color.dark_red); userMentionSelfColor = ContextCompat.getColor(context, R.color.dark_blue); } public Spanned convert() { mReader.setContentHandler(this); try { mReader.parse(new InputSource(new StringReader(mSource))); } catch (IOException | SAXException e) { // We are reading from a string. There should not be IO problems. 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 && 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 emite the linebreaks when we handle the close // tag. } else if (tag.equalsIgnoreCase("p")) { handleP(mSpannableStringBuilder); } else if (tag.equalsIgnoreCase("div")) { handleP(mSpannableStringBuilder); } 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")) { handleP(mSpannableStringBuilder); start(mSpannableStringBuilder, new Blockquote()); } else if (tag.equalsIgnoreCase("tt")) { start(mSpannableStringBuilder, new Monospace()); } else if (tag.equalsIgnoreCase("a")) { startA(mSpannableStringBuilder, attributes, mBaseUri); } else if (tag.equalsIgnoreCase("span") && "user-mention".equals(attributes.getValue("class"))) { startSpan(mSpannableStringBuilder, attributes); } else if (tag.equalsIgnoreCase("u")) { start(mSpannableStringBuilder, new Underline()); } else if (tag.equalsIgnoreCase("sup")) { start(mSpannableStringBuilder, new Super()); } else if (tag.equalsIgnoreCase("sub")) { start(mSpannableStringBuilder, new Sub()); } else if (tag.equalsIgnoreCase("code")) { start(mSpannableStringBuilder, new InlineCode()); } else if (tag.equalsIgnoreCase("pre")) { start(mSpannableStringBuilder, new CodeBlock()); } else if (tag.length() == 2 && Character.toLowerCase(tag.charAt(0)) == 'h' && tag.charAt(1) >= '1' && tag.charAt(1) <= '6') { handleP(mSpannableStringBuilder); start(mSpannableStringBuilder, new Header(tag.charAt(1) - '1')); } else if (tag.equalsIgnoreCase("img")) { String cssClass = attributes.getValue("", "class"); if (cssClass != null && cssClass.equals("emoji")) { startImg(mSpannableStringBuilder, attributes, mEmojiGetter); } else { startImg(mSpannableStringBuilder, attributes, mImageGetter); } } else if (mTagHandler != null) { mTagHandler.handleTag(true, tag, mSpannableStringBuilder, mReader); } } private class CustomQuoteSpan extends QuoteSpan { private static final int STRIPE_WIDTH = 10; private static final int GAP_WIDTH = 20; public CustomQuoteSpan() { super(0xffdddddd); // grey color } @Override public int getLeadingMargin(boolean first) { return STRIPE_WIDTH + GAP_WIDTH; } public void drawLeadingMargin(Canvas c, Paint p, int x, int dir, int top, int baseline, int bottom, CharSequence text, int start, int end, boolean first, Layout layout) { Paint.Style style = p.getStyle(); int color = p.getColor(); p.setStyle(Paint.Style.FILL); p.setColor(getColor()); c.drawRect(x, top, x + dir * STRIPE_WIDTH, bottom, p); p.setStyle(style); p.setColor(color); } } private void handleEndTag(String tag) { if (tag.equalsIgnoreCase("br")) { handleBr(mSpannableStringBuilder); } else if (tag.equalsIgnoreCase("p")) { handleP(mSpannableStringBuilder); } else if (tag.equalsIgnoreCase("div")) { handleP(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")) { handleP(mSpannableStringBuilder); end(mSpannableStringBuilder, Blockquote.class, new CustomQuoteSpan()); } else if (tag.equalsIgnoreCase("tt")) { end(mSpannableStringBuilder, Monospace.class, new TypefaceSpan(MONOSPACE)); } else if (tag.equalsIgnoreCase("a")) { endA(mSpannableStringBuilder); } else if (tag.equalsIgnoreCase("span")) { endSpan(mSpannableStringBuilder); } else if (tag.equalsIgnoreCase("u")) { end(mSpannableStringBuilder, Underline.class, new UnderlineSpan()); } 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.equalsIgnoreCase("code")) { endMultiple(mSpannableStringBuilder, InlineCode.class, new Object[] { new TypefaceSpan(MONOSPACE), new ForegroundColorSpan(0xffdd1144) // pink }); } else if (tag.equalsIgnoreCase("pre")) { end(mSpannableStringBuilder, CodeBlock.class, new TypefaceSpan(MONOSPACE)); } else if (tag.length() == 2 && Character.toLowerCase(tag.charAt(0)) == 'h' && tag.charAt(1) >= '1' && tag.charAt(1) <= '6') { handleP(mSpannableStringBuilder); endHeader(mSpannableStringBuilder); } else if (mTagHandler != null) { mTagHandler.handleTag(false, tag, mSpannableStringBuilder, mReader); } } private static void handleP(SpannableStringBuilder text) { int len = text.length(); if (len >= 1 && text.charAt(len - 1) == '\n') { if (len >= 2 && text.charAt(len - 2) == '\n') { return; } text.append("\n"); return; } if (len != 0) { text.append("\n\n"); } } private static void handleBr(SpannableStringBuilder text) { text.append("\n"); } private static Object getLast(Spanned text, Class kind) { /* * This knows that the last returned object from getSpans() will be the * most recently added. */ Object[] objs = text.getSpans(0, text.length(), kind); if (objs.length == 0) { return null; } else { return objs[objs.length - 1]; } } private static void start(SpannableStringBuilder text, Object mark) { int len = text.length(); text.setSpan(mark, len, len, Spannable.SPAN_MARK_MARK); } private static void endMultiple(SpannableStringBuilder text, Class kind, Object[] replArray) { int len = text.length(); Object obj = getLast(text, kind); int where = text.getSpanStart(obj); text.removeSpan(obj); if (where != len) { for (Object repl : replArray) { text.setSpan(repl, where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } } private static void end(SpannableStringBuilder text, Class kind, Object repl) { int len = text.length(); Object obj = getLast(text, kind); int where = text.getSpanStart(obj); text.removeSpan(obj); if (where != len) { text.setSpan(repl, where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } private static void startImg(SpannableStringBuilder text, Attributes attributes, Html.ImageGetter img) { String src = attributes.getValue("", "src"); Drawable d = null; if (img != null) { d = img.getDrawable(src); } if (d == null) { // don't draw anything return; } int len = text.length(); text.append("\uFFFC"); text.setSpan(new ImageSpan(d, src), len, text.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } private static void startFont(SpannableStringBuilder text, Attributes attributes) { String color = attributes.getValue("", "color"); String face = attributes.getValue("", "face"); int len = text.length(); text.setSpan(new Font(color, face), len, len, Spannable.SPAN_MARK_MARK); } private static void endFont(SpannableStringBuilder text) { int len = text.length(); Object obj = getLast(text, Font.class); int where = text.getSpanStart(obj); text.removeSpan(obj); if (where != len) { Font f = (Font) obj; if (!TextUtils.isEmpty(f.mColor)) { if (f.mColor.startsWith("@")) { Resources res = Resources.getSystem(); String name = f.mColor.substring(1); int colorRes = res.getIdentifier(name, "color", "android"); if (colorRes != 0) { ColorStateList colors = res.getColorStateList(colorRes); text.setSpan(new TextAppearanceSpan(null, 0, 0, colors, null), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } else { int c = getHtmlColor(f.mColor); if (c != -1) { text.setSpan(new ForegroundColorSpan(c | 0xFF000000), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } } if (f.mFace != null) { text.setSpan(new TypefaceSpan(f.mFace), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } } private static void startSpan(SpannableStringBuilder text, Attributes attributes) { String email = attributes.getValue("data-user-email"); int len = text.length(); text.setSpan(new Href(email), len, len, Spannable.SPAN_MARK_MARK); } private static void endSpan(SpannableStringBuilder text) { int len = text.length(); Object obj = getLast(text, Href.class); int where = text.getSpanStart(obj); text.removeSpan(obj); if (where != len) { Href h = (Href) obj; if (h != null && h.mHref != null) { if (ZulipApp.get().getEmail().equals(h.mHref)) { text.setSpan(new ForegroundColorSpan(userMentionSelfColor), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } else { text.setSpan(new ProfileSpan(h.mHref, userMentionColor), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } } } private static void startA(SpannableStringBuilder text, Attributes attributes, String baseUri) { String href = attributes.getValue("", "href"); if (href != null && !href.startsWith("http")) { String prefix; if (!href.startsWith("/")) { prefix = baseUri + "/"; } else { prefix = baseUri; } href = prefix + href; } int len = text.length(); text.setSpan(new Href(href), len, len, Spannable.SPAN_MARK_MARK); } private static void endA(SpannableStringBuilder text) { int len = text.length(); Object obj = getLast(text, Href.class); int where = text.getSpanStart(obj); text.removeSpan(obj); if (where != len) { Href h = (Href) obj; if (h.mHref != null) { text.setSpan(new URLSpan(h.mHref), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } } private static void endHeader(SpannableStringBuilder text) { int len = text.length(); Object obj = getLast(text, Header.class); int where = text.getSpanStart(obj); text.removeSpan(obj); // Back off not to change only the text, not the blank line. while (len > where && text.charAt(len - 1) == '\n') { len--; } if (where != len) { Header h = (Header) obj; text.setSpan(new RelativeSizeSpan(HEADER_SIZES[h.mLevel]), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); text.setSpan(new StyleSpan(Typeface.BOLD), where, len, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); } } 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 Big { } private static class Small { } private static class Monospace { } private static class Blockquote { } private static class Super { } private static class Sub { } private static class InlineCode { } private static class CodeBlock { } private static class Font { public String mColor; public String mFace; public Font(String color, String face) { mColor = color; mFace = face; } } private static class Href { public String mHref; public Href(String href) { mHref = href; } } private static class Header { private int mLevel; public Header(int level) { mLevel = level; } } private static HashMap<String, Integer> buildColorMap() { HashMap<String, Integer> map = new HashMap<>(); map.put("aqua", 0x00FFFF); map.put("black", 0x000000); map.put("blue", 0x0000FF); map.put("fuchsia", 0xFF00FF); map.put("green", 0x008000); map.put("grey", 0x808080); map.put("lime", 0x00FF00); map.put("maroon", 0x800000); map.put("navy", 0x000080); map.put("olive", 0x808000); map.put("purple", 0x800080); map.put("red", 0xFF0000); map.put("silver", 0xC0C0C0); map.put("teal", 0x008080); map.put("white", 0xFFFFFF); map.put("yellow", 0xFFFF00); return map; } /** * Converts an HTML color (named or numeric) to an integer RGB value. * * @param color Non-null color string. * @return A color value, or {@code -1} if the color string could not be * interpreted. */ private static int getHtmlColor(String color) { Integer i = COLORS.get(color.toLowerCase()); if (i != null) { return i; } else { try { return convertValueToInt(color, -1); } catch (NumberFormatException nfe) { return -1; } } } /** * Copied from com.android.internal.util.XmlUtils from Android source */ private static int convertValueToInt(CharSequence charSeq, int defaultValue) { if (null == charSeq) return defaultValue; String nm = charSeq.toString(); // XXX This code is copied from Integer.decode() so we don't // have to instantiate an Integer! int value; int sign = 1; int index = 0; int len = nm.length(); int base = 10; if ('-' == nm.charAt(0)) { sign = -1; index++; } if ('0' == nm.charAt(index)) { // Quick check for a zero by itself if (index == (len - 1)) return 0; char c = nm.charAt(index + 1); if ('x' == c || 'X' == c) { index += 2; base = 16; } else { index++; base = 8; } } else if ('#' == nm.charAt(index)) { index++; base = 16; } return Integer.parseInt(nm.substring(index), base) * sign; } /** <<<<<<< e370c9bc00e8f6b33b1d12a44b4c70a7f063c8b9 * Parses Spanned text for existing html links and reapplies them after the text has been Linkified ======= * Parses Spanned text for existing html links and reapplies them. >>>>>>> Issue #168 bugfix for links not being clickable, adds autoLink feature including web, phone, map and email * @see <a href="https://developer.android.com/reference/android/text/util/Linkify.html">Linkify</a> * * @param spann * @param mask bitmask to define which kinds of links will be searched and applied (e.g. <a href="https://developer.android.com/reference/android/text/util/Linkify.html#ALL">Linkify.ALL</a>) * @return */ public static Spanned linkifySpanned(@NonNull final Spanned spann, final int mask) { URLSpan[] existingSpans = spann.getSpans(0, spann.length(), URLSpan.class); List<Pair<Integer, Integer>> links = new ArrayList<>(); for (URLSpan urlSpan : existingSpans) { links.add(new Pair<>(spann.getSpanStart(urlSpan), spann.getSpanEnd(urlSpan))); } Linkify.addLinks((Spannable) spann, mask); // add the links back in for (int i = 0; i < existingSpans.length; i++) { ((Spannable) spann).setSpan(existingSpans[i], links.get(i).first, links.get(i).second, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); } return spann; } }