TextView显示网络图片，我用android2.3的系统，可以显示图片出来，并且如果图片比较大，应用会卡的现象，肯定是因为使用主线程去获取网络图片造成的，但如果我用android4.0以上的系统运行，则不能显示图片，只显示小方框。
究其原因，是在4.0的系统上执行的时候报错了，异常是：android.os.NetworkOnMainThreadException 经过查文档，原来是4.0系统不允许主线程(UI线程)访问网络，因此导致了其异常。说白了就是在主线程*问网络，会造成主线程挂起，系统不允许使用了。
原文来自铃不铃不铃的博客：http://www.mjix.com/archives/1046.html
此处有作部分修改，代码独立。图片实现异步加载。解决上述问题
用法，调用代码activity
//TextView 控件
textViewContent = (TextView) getActivity().findViewById(R.id.textview_prodcut_detail_more_zp_content);
//HTML文本
zp_content = "测试图片信息：<br><img src=\"http://b2c.zeeeda.com/upload/2013/05/10/136814766742544.jpg\" />";
//默认图片，无图片或没加载完显示此图片
Drawable defaultDrawable = MainActivity.ma.getResources().getDrawable(R.drawable.stub);
//调用
Spanned sp = Html.fromHtml(zp_content, new HtmlImageGetter(textViewContent, "/esun_msg", defaultDrawable), null);
textViewContent.setText(sp);
HtmlImageGetter类
mport java.io.InputStream; import android.graphics.Canvas;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.os.Environment;
import android.text.Html.ImageGetter;
import android.util.Log;
import android.widget.TextView; public class HtmlImageGetter implements ImageGetter{
private TextView _htmlText;
private String _imgPath;
private Drawable _defaultDrawable;
private String TAG = "HtmlImageGetter"; public HtmlImageGetter(TextView htmlText, String imgPath, Drawable defaultDrawable){
_htmlText = htmlText;
_imgPath = imgPath;
_defaultDrawable = defaultDrawable;
} @Override
public Drawable getDrawable(String imgUrl) { String imgKey = String.valueOf(imgUrl.hashCode());
String path = Environment.getExternalStorageDirectory() + _imgPath;
FileUtil.createPath(path); String[] ss = imgUrl.split("\\.");
String imgX = ss[ss.length-1];
imgKey = path+"/" + imgKey+"."+imgX; if(FileUtil.exists(imgKey)){
Drawable drawable = FileUtil.getImageDrawable(imgKey);
if(drawable != null){
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
return drawable;
}else{
Log.v(TAG,"load img:"+imgKey+":null");
}
} URLDrawable urlDrawable = new URLDrawable(_defaultDrawable);
new AsyncThread(urlDrawable).execute(imgKey, imgUrl);
return urlDrawable;
} private class AsyncThread extends AsyncTask<String, Integer, Drawable> {
private String imgKey;
private URLDrawable _drawable; public AsyncThread(URLDrawable drawable){
_drawable = drawable;
} @Override
protected Drawable doInBackground(String... strings) {
imgKey = strings[0];
InputStream inps = NetWork.getInputStream(strings[1]);
if(inps == null) return _drawable; FileUtil.saveFile(imgKey, inps);
Drawable drawable = Drawable.createFromPath(imgKey);
return drawable;
} public void onProgressUpdate(Integer... value) { } @Override
protected void onPostExecute(Drawable result) {
_drawable.setDrawable(result);
_htmlText.setText(_htmlText.getText());
}
} public class URLDrawable extends BitmapDrawable { private Drawable drawable; public URLDrawable(Drawable defaultDraw){
setDrawable(defaultDraw);
} private void setDrawable(Drawable ndrawable){
drawable = ndrawable;
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable
.getIntrinsicHeight());
setBounds(0, 0, drawable.getIntrinsicWidth(), drawable
.getIntrinsicHeight());
} @Override
public void draw(Canvas canvas) {
drawable.draw(canvas);
}
}
}
NetWork 类
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.zip.GZIPInputStream;
import java.util.zip.InflaterInputStream; import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.entity.BufferedHttpEntity;
import org.apache.http.impl.client.DefaultHttpClient; import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log; public class NetWork {
private static String TAG = "NetWork"; public static String getHttpData(String baseUrl){
return getHttpData(baseUrl, "GET", "", null);
} public static String postHttpData(String baseUrl, String reqData){
return getHttpData(baseUrl, "POST", reqData, null);
} public static String postHttpData(String baseUrl, String reqData, HashMap<String, String> propertys){
return getHttpData(baseUrl, "POST", reqData, propertys);
} /**
* 获取赛事信息
* @return
*/
public static String getHttpData(String baseUrl, String method, String reqData, HashMap<String, String> propertys){
String data = "", str;
PrintWriter outWrite = null;
InputStream inpStream = null;
BufferedReader reader = null; HttpURLConnection urlConn = null;
try{
URL url = new URL(baseUrl);
urlConn = (HttpURLConnection)url.openConnection();
//启用gzip压缩
urlConn.addRequestProperty("Accept-Encoding", "gzip, deflate");
urlConn.setRequestMethod(method);
urlConn.setDoOutput(true);
urlConn.setConnectTimeout(3000); if(propertys != null && !propertys.isEmpty()){
Iterator<Map.Entry<String, String>> props = propertys.entrySet().iterator();
Map.Entry<String, String> entry;
while (props.hasNext()){
entry = props.next();
urlConn.setRequestProperty(entry.getKey(), entry.getValue());
}
} outWrite = new PrintWriter(urlConn.getOutputStream());
outWrite.print(reqData);
outWrite.flush(); urlConn.connect(); //获取数据流
inpStream = urlConn.getInputStream();
String encode = urlConn.getHeaderField("Content-Encoding"); //如果通过gzip
if(encode !=null && encode.indexOf("gzip") != -1){
Log.v(TAG, "get data :" + encode);
inpStream = new GZIPInputStream(inpStream);
}else if(encode != null && encode.indexOf("deflate") != -1){
inpStream = new InflaterInputStream(inpStream);
} reader = new BufferedReader(new InputStreamReader(inpStream)); while((str = reader.readLine()) != null){
data += str;
}
}catch (MalformedURLException ex){
ex.printStackTrace();
}catch (IOException ex){
ex.printStackTrace();
}finally{
if(reader !=null && urlConn!=null){
try {
outWrite.close();
inpStream.close();
reader.close();
urlConn.disconnect();
} catch (IOException ex) {
ex.printStackTrace();
}
}
} Log.d(TAG, "[Http data]["+baseUrl+"]:" + data);
return data;
} /**
* 获取Image信息
* @return
*/
public static Bitmap getBitmapData(String imgUrl){
Bitmap bmp = null;
Log.d(TAG, "get imgage:"+imgUrl); InputStream inpStream = null;
try{
HttpGet http = new HttpGet(imgUrl);
HttpClient client = new DefaultHttpClient();
HttpResponse response = (HttpResponse)client.execute(http);
HttpEntity httpEntity = response.getEntity();
BufferedHttpEntity bufferedHttpEntity = new BufferedHttpEntity(httpEntity); //获取数据流
inpStream = bufferedHttpEntity.getContent();
bmp = BitmapFactory.decodeStream(inpStream); }catch (Exception ex){
ex.printStackTrace();
}finally{
if(inpStream !=null){
try {
inpStream.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
} return bmp;
} /**
* 获取url的InputStream
* @param urlStr
* @return
*/
public static InputStream getInputStream(String urlStr){
Log.d(TAG, "get http input:"+urlStr);
InputStream inpStream = null;
try{
HttpGet http = new HttpGet(urlStr);
HttpClient client = new DefaultHttpClient();
HttpResponse response = (HttpResponse)client.execute(http);
HttpEntity httpEntity = response.getEntity();
BufferedHttpEntity bufferedHttpEntity = new BufferedHttpEntity(httpEntity); //获取数据流
inpStream = bufferedHttpEntity.getContent();
}catch (Exception ex){
ex.printStackTrace();
}finally{
if(inpStream !=null){
try {
inpStream.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
return inpStream;
}
}
FileUtil类
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream; import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Environment;
import android.util.Log; public class FileUtil {
private static int FILE_SIZE = 4*1024;
private static String TAG = "FileUtil"; public static boolean hasSdcard(){
String status = Environment.getExternalStorageState();
if(status.equals(Environment.MEDIA_MOUNTED)){
return true;
}
return false;
} public static boolean createPath(String path){
File f = new File(path);
if(!f.exists()){
Boolean o = f.mkdirs();
Log.i(TAG, "create dir:"+path+":"+o.toString());
return o;
}
return true;
} public static boolean exists(String file){
return new File(file).exists();
} public static File saveFile(String file, InputStream inputStream){
File f = null;
OutputStream outSm = null; try{
f = new File(file);
String path = f.getParent();
if(!createPath(path)){
Log.e(TAG, "can't create dir:"+path);
return null;
} if(!f.exists()){
f.createNewFile();
} outSm = new FileOutputStream(f);
byte[] buffer = new byte[FILE_SIZE];
while((inputStream.read(buffer)) != -1){
outSm.write(buffer);
}
outSm.flush();
}catch (IOException ex) {
ex.printStackTrace();
return null; }finally{
try{
if(outSm != null) outSm.close();
}catch (IOException ex) {
ex.printStackTrace();
}
}
Log.v(TAG,"[FileUtil]save file:"+file+":"+Boolean.toString(f.exists())); return f;
} public static Drawable getImageDrawable(String file){
if(!exists(file)) return null;
try{
InputStream inp = new FileInputStream(new File(file));
return BitmapDrawable.createFromStream(inp, "img");
}catch (Exception ex){
ex.printStackTrace();
}
return null;
}
}