android textview 顯示html方法解析

現在網路的繁盛時代，光文字是不能滿足人們的胃口的，圖片，flash，音頻，視頻就成為瀏覽網頁的主流顯示，在手機上也一樣。在手機上顯示從網路端擷取的資料顯示，大家很自然的想起兩種方式，一種就是webview，一種就是TextView。當然webView直接顯示html頁面就行了，我主要說的TextView顯示html內容。
首先，說下TextView到底支援那些標籤呢，通過對源碼的查看，發現Textview可以解析一部分html標籤，如： 複製代碼 代碼如下:<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>
<u>

大家想究其根本可以查看android.text.Html源碼，其中有一段這樣寫： 複製代碼 代碼如下: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("em")) {
start(mSpannableStringBuilder, new Bold());
} else if (tag.equalsIgnoreCase("b")) {
start(mSpannableStringBuilder, new Bold());
} else if (tag.equalsIgnoreCase("strong")) {
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);
} 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.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")) {
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")) {
handleP(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("div")) {
handleP(mSpannableStringBuilder);
} else if (tag.equalsIgnoreCase("em")) {
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("strong")) {
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 QuoteSpan());
} 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("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') {
handleP(mSpannableStringBuilder);
endHeader(mSpannableStringBuilder);
} else if (mTagHandler != null) {
mTagHandler.handleTag(false, tag, mSpannableStringBuilder, mReader);
}
}

通過源碼可以看到，除了預設的一些標籤，其還支援自訂標籤；看下面代碼：
else if (mTagHandler != null) {
mTagHandler.handleTag(false, tag, mSpannableStringBuilder, mReader);
}
系統會調用mTagHandler的handleTag方法。所以，我們可以實現此介面，來解析自己定義的標籤類型。
具體的，自己可以看一下下面執行個體: 複製代碼 代碼如下:package com.mxgsa.tvimg;
import org.xml.sax.XMLReader;
import android.content.Context;
import android.content.Intent;
import android.text.Editable;
import android.text.Html.TagHandler;
import android.text.Spanned;
import android.text.style.ClickableSpan;
import android.view.View;
import android.view.View.OnClickListener;
public class MxgsaTagHandler implements TagHandler{
private int sIndex = 0;
private int eIndex=0;
private final Context mContext;
public MxgsaTagHandler(Context context){
mContext=context;
}
public void handleTag(boolean opening, String tag, Editable output, XMLReader xmlReader) {
// TODO Auto-generated method stub
if (tag.toLowerCase().equals("mxgsa")) {
if (opening) {
sIndex=output.length();
}else {
eIndex=output.length();
output.setSpan(new MxgsaSpan(), sIndex, eIndex, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
}
}
}
private class MxgsaSpan extends ClickableSpan implements OnClickListener{
@Override
public void onClick(View widget) {
// TODO Auto-generated method stub
//具體代碼，可以是跳轉頁面，可以是彈出對話方塊，下面是跳轉頁面
mContext.startActivity(new Intent(mContext,MainActivity.class));
}
}
}

調用頁面： 複製代碼 代碼如下:package com.mxgsa.tvimg;
import android.app.Activity;
import android.os.Bundle;
import android.text.Html;
import android.text.method.LinkMovementMethod;
import android.widget.TextView;
public class MxgsaActivity extends Activity{
private TextView tView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mxgsa_activity);
findControl();
setData();
}
private void findControl() {
tView = (TextView) findViewById(R.id.tvImage);
}
private void setData() {
// TODO Auto-generated method stub
final String sText = "測試自訂標籤：<br><h1><mxgsa>測試自訂標籤</mxgsa></h1>";
tView.setText(Html.fromHtml(sText, null, new MxgsaTagHandler(this)));
tView.setClickable(true);
tView.setMovementMethod(LinkMovementMethod.getInstance());
}
}

下篇將會講帶圖片的html文本顯示！待續 。。。。。