从网络文本图片

一个简单的例子来说明：

public class MainActivity extends Activity{
TextView my_textview;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
my_textview=(TextView)findViewById(R.id.my_textview);
new MyAsyncTask().execute("http://www.baidu.com");//下载百度首页的图片
}
public class MyAsyncTask extends AsyncTask<String, Void, String>{


@Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
return downloadText(params[0]);
}
@Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
my_textview.setText(result);
}
}


private InputStream openHttpConnection(String urlString) throws IOException{
InputStream in=null;
int response=-1;
URL url=new URL(urlString);//构造URL对象
URLConnection conn=url.openConnection();//打开http链接
if(!(conn instanceof HttpURLConnection)){
throw new IOException("Not an Http Contention");

}
HttpURLConnection httpURLConnection=(HttpURLConnection)conn;
httpURLConnection.setInstanceFollowRedirects(true);//可以进行跳转
httpURLConnection.setRequestMethod("Get");
httpURLConnection.connect();
response=httpURLConnection.getResponseCode();
if(response==HttpURLConnection.HTTP_OK){
in=httpURLConnection.getInputStream();
}

return in;

}
private String downloadText(String url){//下载文本数据
InputStream in=null;
try {
in=openHttpConnection(url);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(in));
String line=null;
StringBuffer result=new StringBuffer();//返回结果
try {
while((line=bufferedReader.readLine())!=null){
result.append(line);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return result.toString();

}

}