【发布时间】：2013-12-24 17:55:57
【问题描述】：
我正在尝试将每个 http 调用的每个输出数据保存在 asynctask 中。但我无法在文件中看到任何数据。非常感谢任何帮助。提前致谢。
final String[] ar={"1","2","3",.............,"25"}
filename="test_file";
myFile = new File("/sdcard/"+filename);
try {
myFile.createNewFile();
fOut = new FileOutputStream(myFile);
} catch (FileNotFoundException e1) {
e1.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
myOutWriter = new OutputStreamWriter(fOut);
for ( j = 0; j < ar.length; j++) {
u="http://www.example.com/"+ar[j];
JSONParser jParser=new JSONParser();
new MyAsyncTask().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,u);
}
try {
myOutWriter.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
class MyAsyncTask extends AsyncTask<String, String, Void> {
private ProgressDialog progressDialog = new ProgressDialog(MainActivity.this);
InputStream inputStream = null;
String result = "";
protected void onPreExecute() {
progressDialog.setMessage("Downloading your data...");
progressDialog.show();
progressDialog.setOnCancelListener(new OnCancelListener() {
public void onCancel(DialogInterface arg0) {
MyAsyncTask.this.cancel(true);
}
});
}
@Override
protected Void doInBackground(String... params) {
String url_select = params[0];
try {
HttpClient httpclient = new DefaultHttpClient();
HttpResponse httpResponse = httpclient.execute(new HttpGet(url_select));
// receive response as inputStream
inputStream = httpResponse.getEntity().getContent();
//
// // Read content & Log
// inputStream = httpEntity.getContent();
} catch (UnsupportedEncodingException e1) {
Log.e("UnsupportedEncodingException", e1.toString());
e1.printStackTrace();
} catch (ClientProtocolException e2) {
Log.e("ClientProtocolException", e2.toString());
e2.printStackTrace();
} catch (IllegalStateException e3) {
Log.e("IllegalStateException", e3.toString());
e3.printStackTrace();
} catch (IOException e4) {
Log.e("IOException", e4.toString());
e4.printStackTrace();
}
// Convert response to string using String Builder
try {
BufferedReader bReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"), 8);
StringBuilder sBuilder = new StringBuilder();
String line = null;
while ((line = bReader.readLine()) != null) {
sBuilder.append(line + "\n");
}
inputStream.close();
result = sBuilder.toString();
} catch (Exception e) {
Log.e("StringBuilding & BufferedReader", "Error converting result " + e.toString());
}
return null;
} // protected Void doInBackground(String... params)
protected void onPostExecute(Void v) {
//parse JSON data
try{
JSONObject jArray = new JSONObject(result);
String name = jArray.getString("name");
if (name!=null) {
Log.w("idname", name);
//
myOutWriter.append(name).append("\r\n");
//
Toast.makeText(getBaseContext(), name, 5).show();
}
// End Loop
this.progressDialog.dismiss();
} catch (JSONException e) {
Log.e("JSONException", "Error: " + e.toString());
} // catch (JSONException e)
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} // protected void onPostExecute(Void v)
} //class MyAsyncTask extends AsyncTask<String, String, Void>
【问题讨论】：
-
在do inBackground方法中将u改为params[0]
-
在
onPostExecute中记录name并检查logcat -
@raj 我已经编辑了代码。
-
@jason 为什么在 for 循环
new MyAsyncTask().execute(u);和这个new MyAsyncTask().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,u);中？您可以将 url 数组传递给 doInbackground 并在那里下载数据。无需在 for 循环中调用 execute。您是否还记录了姓名并签入了 logcat？ -
@Raghunandan 对不起先生，我的错误。我没有发布您的代码。它现在已编辑。日志名称正在工作。