android的TextView使用Html来处理图片显示、字体样式、超链接等
一、[Android实例]实现TextView里的文字有不同颜色
转eoe：http://www.eoeandroid.com/thread-4496-1-1.html
import android.text.Html;
TextView t3 = (TextView) findViewById(R.id.text3);
??????? t3.setText(
??????????? Html.fromHtml(
??????????????? "<b>text3:</b>? Text with a " +
??????????????? "<a href="http://www.google.com">link</a> " +
??????????????? "created in the Java source code using HTML."));
二、TextView显示html文件中的图片
转javaeye：http://da-en.javaeye.com/blog/712415
我们知道要让TextView解析和显示Html代码。可以使用
Spanned text = Html.fromHtml(source);
tv.setText(text);
来实现，这个用起来简单方便。
但是，怎样让TextView也显示Html中<image>节点的图像呢？
我们可以看到fromHtml还有另一个重构：
fromHtml(String source, Html.ImageGetter imageGetter, Html.TagHandler tagHandler)
实现一下ImageGetter就可以让图片显示了：
ImageGetter imgGetter = new Html.ImageGetter() {
???????????? @Override
???????????? public Drawable getDrawable(String source) {
?????????????????? Drawable drawable = null;
?????????????????? drawable = Drawable.createFromPath(source);? // Or fetch it from the URL
?????????????????? // Important
?????????????????? drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable
???????????????????????????????? .getIntrinsicHeight());
?????????????????? return drawable;
???????????? }
};
至于TagHandler，我们这里不需要使用，可以直接传null。
参考文档：
http://tech-droid.blogspot.com/2010/06/textview-with-html-content.html英语好的朋友就直接看英文文档吧。
三、Android---文字中插入表情
??? 转载自：http://blog.163.com/spf9190@126/blog/static/50207531201091545954587/
?????? 这段时间在做一个短信项目，需要实现短信中插入表情的功能，本一位非常困难，经过一段时间的研究，发现还是比较簡単的，现在总结如下。
?????? 以短信输入框为例，短信的输入框是一个EditText，它的append方法不仅可以加入字符串，还可以添加HTML标记。以下就是使用HTML标记添加表情的具体操作。
?? 首先需要构建一个ImageGetter，作用是通过HTML标记获得对应在res目录下的图片：
?????? ImageGetter imageGetter = new ImageGetter() {?
??????? @Override
?????? public Drawable getDrawable(String source) {
?????? int id = Integer.parseInt(source);
????? //根据id从资源文件中获取图片对象
?????? Drawable d = getResources().getDrawable(id);
?????? d.setBounds(0, 0, d.getIntrinsicWidth(),d.getIntrinsicHeight());
??????? return d;
?????? }
?????? };?????????
然后就可以直接往EditText视图中添加
?????? inputLable.append(Html.fromHtml("<img src='"+clickedImageId+"'/>", imageGetter, null));?????????????????
? 其中 Html.fromHtml("<img src='"+clickedImageId+"'/>"就是HTML的图片标记，在Android中支持了部分HTML标记的使用（这方面我还在继续研究），HTML标记必须被Html.fromHtml修饰。imageGetter即为之前创建的ImageGetter类型的对象。
很简单的几句代码就解决了问题，不仅在EditText中，在TextView中同样可以这样插入图片。
效果图：
四、android 短信字符转表情显示过程
android 的短信实现方式普通用户适应的话需要长时间的使用才能习惯，将andorid的短信模式设置成我们常用的（一般人用户）的习惯。在查看字符转图片的过程中可以猜测出腾讯的QQ表情的原理应该是一样的只是在传送非常用的表情时是将byte数据转换为image.
以下代码摘录至android源码里面的MMS项目，其中的
package com.android.mms.ui 里的 MessageListItem.java
package com.android.mms.util 里的 SmileyParser.java
/***
???? *
???????? * 此方法描述的是：?? 注意此方法在做表情转换的准备了
???????? * @author:wujun@cqghong.com,ppwuyi@sohu.com
???????? * @version: 2010-5-13 下午03:31:13
???? */
??? private void bindCommonMessage(final MessageItem msgItem) {
??????? if (mDownloadButton != null) {
??????????? mDownloadButton.setVisibility(View.GONE);
??????????? mDownloadingLabel.setVisibility(View.GONE);
??????? }
??????? // Since the message text should be concatenated with the sender's
??????? // address(or name), I have to display it here instead of
??????? // displaying it by the Presenter.
??????? mBodyTextView.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
??????? // Get and/or lazily set the formatted message from/on the
??????? // MessageItem. Because the MessageItem instances come from a
??????? // cache (currently of size ~50), the hit rate on avoiding the
??????? // expensive formatMessage() call is very high.
??????? CharSequence formattedMessage = msgItem.getCachedFormattedMessage();
??????? if (formattedMessage == null) { //肯定为null应为msgItem.formattedMessage从诞生来就没被注意过一次
??????????? formattedMessage = formatMessage(msgItem.mContact, msgItem.mBody,?? //重点到了
???????????????????????????????????????????? msgItem.mSubject, msgItem.mTimestamp,
???????????????????????????????????????????? msgItem.mHighlight);
??????????? msgItem.setCachedFormattedMessage(formattedMessage);
??????? }
??????? mBodyTextView.setText(formattedMessage);
??????? if (msgItem.isSms()) {
??????????? hideMmsViewIfNeeded();
??????? } else {
??????????? Presenter presenter = PresenterFactory.getPresenter(
??????????????????? "MmsThumbnailPresenter", mContext,
??????????????????? this, msgItem.mSlideshow);
??????????? presenter.present();
??????????? if (msgItem.mAttachmentType != WorkingMessage.TEXT) {
??????????????? inflateMmsView();
??????????????? mMmsView.setVisibility(View.VISIBLE);
??????????????? setOnClickListener(msgItem);
??????????????? drawPlaybackButton(msgItem);
??????????? } else {
??????????????? hideMmsViewIfNeeded();
??????????? }
??????? }
??????? drawLeftStatusIndicator(msgItem.mBoxId);
??????? drawRightStatusIndicator(msgItem);
??? }
//------------------------------------------
/***
???? *
???????? * 此方法描述的是：?? 开始转换了哦
???????? * @author:wujun@cqghong.com,ppwuyi@sohu.com
???????? * @version: 2010-5-13 下午03:32:52
???? */
??? private CharSequence formatMessage(String contact, String body, String subject,
?????????????????????????????????????? String timestamp, String highlight) {
??????? CharSequence template = mContext.getResources().getText(R.string.name_colon); //遇到鬼了???? <主题：<xliff:g id="SUBJECT">%s</xliff:g>>"
??????? SpannableStringBuilder buf =?????????????????? //把他当作StringBuffer只是它可以放的不是 String 而已他能放跟多类型的东西
??????????? new SpannableStringBuilder(TextUtils.replace(template,
??????????????? new String[] { "%s" },
??????????????? new CharSequence[] { contact })); //替换成联系人
??????? boolean hasSubject = !TextUtils.isEmpty(subject); //主题
??????? if (hasSubject) {
??????????? buf.append(mContext.getResources().getString(R.string.inline_subject, subject)); //buff先在是 联系人 主题 XXXX????? eg wuyi <主题:dsadasdsa> 我爱我家
??????? }
??????? if (!TextUtils.isEmpty(body)) {
??????????? if (hasSubject) {
??????????????? buf.append(" - "); //如果内容有主题有就+ " - "??? eg wuyi <主题:sdsadsadsa> -
??????????? }
??????????? SmileyParser parser = SmileyParser.getInstance(); //获得表情类了哦
??????????? buf.append(parser.addSmileySpans(body)); //追查 急切关注中
??????? }
??????? if (!TextUtils.isEmpty(timestamp)) {
??????????? buf.append("\n");
??????????? int startOffset = buf.length();
??????????? // put a one pixel high spacer line between the message and the time stamp as requested
??????????? // by the spec.
??????????? //把之间的信息和时间戳的要求间隔一个像素的高线
??????????? //由规范
??????????? buf.append("\n");
??????????? buf.setSpan(new AbsoluteSizeSpan(3), startOffset, buf.length(),
??????????????????? Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
??????????? startOffset = buf.length();
??????????? buf.append(timestamp);
??????????? buf.setSpan(new AbsoluteSizeSpan(12), startOffset, buf.length(),
??????????????????? Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
??????????? // Make the timestamp text not as dark 改变某区域颜色?? 时间的地方为特殊颜色
??????????? int color = mContext.getResources().getColor(R.color.timestamp_color);
??????????? buf.setSpan(new ForegroundColorSpan(color), startOffset, buf.length(),
??????????????????? Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
??????? }
??????? if (highlight != null) {
??????????? int highlightLen = highlight.length();
??????????? String s = buf.toString().toLowerCase();
??????????? int prev = 0;
??????????? while (true) {
??????????????? int index = s.indexOf(highlight, prev);
??????????????? if (index == -1) {
??????????????????? break;
??????????????? }
??????????????? buf.setSpan(new StyleSpan(Typeface.BOLD), index, index + highlightLen, 0);
??????????????? prev = index + highlightLen;
??????????? }
??????? }
??????? return buf;
??? }
//------------------------
/**
???? * Adds ImageSpans to a CharSequence that replace textual emoticons such
???? * as :-) with a graphical version.
???? *
???? * @param text A CharSequence possibly containing emoticons
???? * @return A CharSequence annotated with ImageSpans covering any
???? *???????? recognized emoticons.
???? * 添加ImageSpans一个CharSequence的表情符号代替文字等???? *如用图形版本:-)。
???? * 核心是把表情字符替换成ImageSpans的对象
???? */
??? public CharSequence addSmileySpans(CharSequence text) {
??????? SpannableStringBuilder builder = new SpannableStringBuilder(text);
??????? Matcher matcher = mPattern.matcher(text);
??????? while (matcher.find()) {
??????????? int resId = mSmileyToRes.get(matcher.group());
??????????? //注意下面的一块有点不好理解哦但是是核心
??????????? builder.setSpan(new ImageSpan(mContext, resId), matcher.start(), matcher.end(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
??????? }
??????? return builder;
??? }
总结：
???? android 在将字符转化为表情图像其核心代码为
builder.setSpan(new ImageSpan(mContext, resId), matcher.start(), matcher.end(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
原理过程是先匹配到表情字符然后通过new ImageSpan(上下文,表情地址)绘制出一个ImageView然后替换掉表情字符。
五、 Android TextView 支持的HTML标签
<a href="...">
<b>
<big>
<blockquote>
<br>
<cite>
<dfn>
<div align="...">
<em>
<font size="..." color="..." face="...">
<h1>
<h2>
<h3>
<h4>
<h5>
<h6>
<i>
<img src="...">
<p>
<small>
<strike>
<strong>
<sub>
<sup>
<tt>
