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我使用下面的代码从 url 读取 HTML 内容。这对于 2.3.3 来说非常有效,但是当我尝试运行相同的代码时,它对于 ICS 不起作用。
我正在尝试将这些 html 内容附加到 edittext
。但当我在 ICS 上运行代码时,它始终为空。可能是什么问题?
public class Quiz1Activity extends Activity {
private static BufferedReader reader = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
EditText ed = (EditText) findViewById(R.id.editText1);
try {
ed.append(getStringFromUrl("http://www.google.com"));
//getInputStreamFromUrl("").close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static InputStream getInputStreamFromUrl(String url){
InputStream contentStream = null;
try{
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = httpclient.execute(new HttpGet(url));
contentStream = response.getEntity().getContent();
} catch(Exception e){
e.printStackTrace();
}
System.out.println("Content stream is " + contentStream);
return contentStream;
}
public static String getStringFromUrl(String url) throws IOException{
reader = new BufferedReader(new InputStreamReader(getInputStreamFromUrl(url)));
StringBuilder sb = new StringBuilder();
try{
String line = null;
while((line = reader.readLine()) != null)
{
sb.append(line);
}
}catch (IOException e){
e.printStackTrace();
}
getInputStreamFromUrl(url).close();
return sb.toString();
}
}
最佳答案
就像 @Vipul Shah 所说,你必须使用 Async Task 将 getInputStreamFromUrl() 移动到另一个线程中,这是 ICS 上的工作:
package com.home.anas;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.widget.EditText;
public class WebPageContentActivity extends Activity {
private EditText ed;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ed = (EditText) findViewById(R.id.editText1);
readWebpage();
}
private class DownloadWebPageTask extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... urls) {
String response = "";
for (String url : urls) {
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
try {
HttpResponse execute = client.execute(httpGet);
InputStream content = execute.getEntity().getContent();
BufferedReader buffer = new BufferedReader(new InputStreamReader(content));
String s = "";
while ((s = buffer.readLine()) != null) {
response += s;
}
} catch (Exception e) {
e.printStackTrace();
}
}
return response;
}
@Override
protected void onPostExecute(String result) {
ed.setText(result);
}
}
public void readWebpage() {
DownloadWebPageTask task = new DownloadWebPageTask();
task.execute(new String[] { "http://www.google.com" });
}
}
关于java - 为什么这不适用于 ICS,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/11133103/