我已经编写了一个程序，可以将我的pdf文件从服务器下载到我的SD卡中，这是正确的下载，但是当我通过我的pdfviewer查看它时，它说无法打开这个文件。 文件大小也是4.5mb，但是下载到我的sdcards pdf文件夹的pdf大小为0。
private void processPDF(String subject_pdf) {
new AsyncTask<Void, Void, String>() {
@Override
protected String doInBackground(Void... params) {
String result = "";
StringBuilder builder = new StringBuilder(100000);
try {
String URL =
"http://192.168.1.3:8082/APP_Server/subject_pdfs_result.jsp?
branch_year="+ type; //type = branches(e.g computers , IT)
HttpClient httpclient = new DefaultHttpClient();
HttpGet httpget = new HttpGet(URL);
HttpResponse response = httpclient.execute(httpget);
InputStream is = response.getEntity().getContent();
BufferedReader buffer = new BufferedReader(new
InputStreamReader(is));
// result = is.toString();
while ((result = buffer.readLine()) != null) {
builder.append(result);
}
} catch (Exception ex) {
ex.printStackTrace();
}
return builder.toString().replaceAll("\\<.*?\\>", "");
}
@Override
protected void onPostExecute(String builder) {
//url has the pdf name
name= builder.replace("\t", "");
image_url =
"http://192.168.1.3:8082/APP_Server/Images/Books_Pdf/" + url;
extStorageDirectory =
Environment.getExternalStorageDirectory().toString();
File folder = new File(extStorageDirectory, "pdf");
folder.mkdir();
File file = new File(folder, name);
try {
file.createNewFile();
} catch (Exception e1) {
e1.printStackTrace();
}
PDFDownloader.DownloadFile(image_url, file);
showPdf();
}
}.execute(null, null, null);
}
private void showPdf() {
File file = new File(Environment.getExternalStorageDirectory() + "/pdf/"
+ name);
PackageManager packageManager = getPackageManager();
Intent testIntent = new Intent(Intent.ACTION_VIEW);
testIntent.setType("application/pdf");
List list = packageManager.queryIntentActivities(testIntent,
PackageManager.MATCH_DEFAULT_ONLY);
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
Uri uri = Uri.fromFile(file);
intent.setDataAndType(uri, "application/pdf");
startActivity(Intent.createChooser(intent, "Open File"));
}
PDFDownloader.java
public static void DownloadFile(String fileURL, File directory) {
try {
FileOutputStream f = new FileOutputStream(directory);
URL u = new URL(fileURL);
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
InputStream in = c.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
while ((len1 = in.read(buffer)) > 0) {
f.write(buffer, 0, len1);
}
f.close();
} catch (Exception e) {
e.printStackTrace();
}
}
我需要一些关于我哪里出错的指导。 谢谢。
答案 0 :(得分：0)
作为我插入的代码工作
public class Tapir extends ListActivity {
// flag for Internet connection status
Boolean isInternetPresent = false;
// Connection detector class
ConnectionDetector cd;
public static final int DIALOG_DOWNLOAD_PROGRESS = 0;
private ProgressDialog mProgressDialog;
public MediaPlayer mp;
private String URLDwnTapir="http://internetwan.xzn.ir/tapir_vocalisation.mp3";
private String URLDwnTapir_pic="http://internetwan.xzn.ir/tapir.jpg";
File sdcard=Environment.getExternalStorageDirectory();
File dir=new File(sdcard.getAbsolutePath()+"/WorldOfSounds/Tapir");
//Objects of files
File Tapir_obj=new File(dir,"Tapir.mp3");
File Tapir_PIC_obj=new File(dir,"Tapir.jpg");
String Tapir=Environment.getExternalStorageDirectory().getAbsolutePath()+"/WorldOfSounds/Tapir/Tapir.jpg";
@Override
public void onBackPressed() {
super.onBackPressed();
if(mp!=null&&mp.isPlaying()){
mp.release();
mp.stop();
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.tapir);
setListAdapter (new ArrayAdapter <String> (this,
android.R.layout.simple_list_item_1,
getResources ().getStringArray(R.array.Tapir_value)));
// creating connection detector class instance
cd = new ConnectionDetector(getApplicationContext());
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
// TODO Auto-generated method stub
super.onListItemClick(l, v, position, id);
switch(position){
case 0:
if(!dir.exists()){
dir.mkdirs();
}
if(Tapir_obj.exists()){
if(mp!=null){
mp.release();
}if(Tapir_PIC_obj.exists()){
LinearLayout linl=(LinearLayout)findViewById(R.id.LinearLayout1);
//FileInputStream streamIn = new FileInputStream(Tapir_PIC_obj);
//Bitmap bitmap = BitmapFactory.decodeStream(streamIn);
//Uri imgUri=Uri.fromFile(Tapir_PIC_obj);
BitmapDrawable d = new BitmapDrawable(Tapir);
linl.setBackgroundDrawable(d);
}else{
StartDwnTapir_pic();
}
final AudioManager mAudioManager = (AudioManager) getSystemService(AUDIO_SERVICE);
final int originalVolume = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
mAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC, mAudioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC), 0);
mp = new MediaPlayer();
mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
mp=MediaPlayer.create(null, Uri.fromFile(Tapir_obj)) ;
mp.start();
mp.setOnCompletionListener(new OnCompletionListener()
{
@Override
public void onCompletion(MediaPlayer mp)
{
mAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC, originalVolume, 0);
}
});
//LinearLayout linl=(LinearLayout)findViewById(R.id.LinearLayout1);
//linl.setBackgroundResource(R.drawable.tapir);
}else{
// get Internet status
isInternetPresent = cd.isConnectingToInternet();
// check for Internet status
if (isInternetPresent) {
// Internet Connection is Present
// make HTTP requests
startDwnTapir_obj();
} else {
// Internet connection is not present
// Ask user to connect to Internet
Toast.makeText(this,"مشکل در اتصال به شبکه اینترنت!",Toast.LENGTH_LONG).show();
}
}//end else
//Toast.makeText(this,"you selected position 0",Toast.LENGTH_LONG).show();
break;
}//end switch
}//end onlistitem
private void startDwnTapir_obj(){
new DwnstartDwnTapir_objAsync().execute(URLDwnTapir);
}
private void StartDwnTapir_pic(){
new StartDwnTapir_picAsync().execute(URLDwnTapir_pic);
}
@Override
protected Dialog onCreateDialog(int id) {
//String SmallFountain = URLDownloadSmallFountain.substring(URLDownloadSmallFountain.lastIndexOf('/') + 1, URLDownloadSmallFountain.length());
// String msg="downloading file : "+SmallFountain;
switch (id) {
case DIALOG_DOWNLOAD_PROGRESS:
mProgressDialog = new ProgressDialog(this);
mProgressDialog.setMessage("downloading file... \n Please wait");
mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
mProgressDialog.setCancelable(false);
mProgressDialog.show();
return mProgressDialog;
default:
return null;
}
}//end onCreatDialog
class DwnstartDwnTapir_objAsync extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
showDialog(DIALOG_DOWNLOAD_PROGRESS);
}
@Override
protected String doInBackground(String... aurl) {
int count;
try {
URL URLDwnTapir = new URL(aurl[0]);
HttpURLConnection conexion = (HttpURLConnection) URLDwnTapir.openConnection();
conexion.connect();
int lenghtOfFile = conexion.getContentLength();
Log.d("ANDRO_ASYNC", "Lenght of file: " + lenghtOfFile);
InputStream input = new BufferedInputStream(URLDwnTapir.openStream());
if(!dir.exists()){
dir.mkdirs();
}
OutputStream output = new FileOutputStream(Tapir_obj);
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
publishProgress("" + (int) ((total * 100) / lenghtOfFile));
output.write(data, 0, count);
}
Log.d("ANDRO_ASYNC", "end download Tapir_obj File ");
output.flush();
output.close();
input.close();
}
catch (Exception e) {}
return null;
}
@Override
protected void onProgressUpdate(String... progress) {
Log.d("ANDRO_ASYNC", progress[0]);
mProgressDialog.setProgress(Integer.parseInt(progress[0]));
}
@Override
protected void onPostExecute(String unused) {
dismissDialog(DIALOG_DOWNLOAD_PROGRESS);
}
}//end Class DwnTapirAsync