I have an AsyncTask to download files one by one, and I make it as a queue, when it's running on android 2.x, good. In android 4.0+ it stop working. Here I passed a ProgressBar to AsyncTask, so it will update the loading progress bar, and indicate where it is.
The strange part is the progress bar will go 100% very quick not match the real size of file. And the length of file output in logcat also wrong...
All tasks will execute serially so it won't hurt the parallel limitation above SDK 11. I guess the problem might be inside the download part, just don't know where it is.
public function download ()
{
.....
if (task != null) {
task.cancel (true);
}
task = new OnlineDownloadTask (progress);
task.execute (url, path);
.....
}
class OnlineDownloadTask extends AsyncTask<String, String, String> {
private final WeakReference<OfflineQueueIndicatorView> progressbarReference;
public OnlineDownloadTask(OfflineQueueIndicatorView progress) {
progressbarReference = new WeakReference<OfflineQueueIndicatorView>(
progress);
}
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(String... aurl) {
int count;
try {
URL url = new URL(aurl[0]);
HttpURLConnection conn = (HttpURLConnection) url
.openConnection();
conn.setConnectTimeout(10000);
conn.setReadTimeout(10000);
conn.setRequestMethod("GET");
conn.setAllowUserInteraction(false);
conn.setDoInput(true);
conn.setDoOutput(true);
conn.connect();
int lengthOfFile = conn.getContentLength();
android.util.Log.v("offline.downloader", lengthOfFile + "");
InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream(aurl[1]);
try {
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
publishProgress(""
+ (int) ((total * 100) / lengthOfFile));
if (stopoffline) {
android.util.Log.v("file.downloader", "stopped");
break;
}
output.write(data, 0, count);
}
if (stopoffline) {
output.flush();
output.close();
input.close();
conn.disconnect();
File file = new File(aurl[1]);
if (file.exists()) {
file.delete();
}
stopoffline = false;
return null;
} else {
output.flush();
output.close();
input.close();
conn.disconnect();
if (DiskCache.getInstance().offlineDirectoryExist(
DiskCache.getInstance().offlineCurrentFolder)) {
} else {
if (!DiskCache
.getInstance()
.makeOfflineFolder(
DiskCache.getInstance().offlineCurrentFolder)) {
return null;
}
}
android.util.Log.v("offline",
DiskCache.getInstance().offlineCurrentFolder);
unzip(aurl[1],
DiskCache.getInstance().offlineCurrentFolder);
DiskCache.getInstance().deleteFile(aurl[1]);
return "succ";
}
} finally {
if (output != null) {
output.flush();
output.close();
}
if (input != null) {
input.close();
}
if (conn != null) {
conn.disconnect();
}
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
protected void onProgressUpdate(String... progress) {
try {
if (progressbarReference != null) {
OfflineQueueIndicatorView p = progressbarReference.get();
if (p != null) {
int i = Integer.parseInt(progress[0]);
p.setProgress(i);
}
}
}
catch (Exception e) {
e.printStackTrace();
}
}
#Override
protected void onPostExecute(String ret) {
try {
if (progressbarReference != null) {
if (ret != null) {
queue.get(currentId).put("state", "complete");
} else {
if (queue != null) {
if (currentId != null) {
queue.get(currentId).put("state", "failed");
}
}
}
}
}
catch (Exception e) {
e.printStackTrace();
}
download();
}
}
It's possible that the newer version of HttpUrlConnection in Android 4.0 is causing the server to use Chunked Transfer Encoding, which is supported in HTTP/1.1. The Android 2.x version may not have supported CTE. When sending a response with CTE (e.g., during file/video streaming), the server will not return a content length. As such, you may want to show an indeterminate ProgressBar when the content length is not available.
I finally found what's wrong after I remove conn.setDoOutput(true), it working well on both android 2.x and 4.x emulator, I think also acj has the point, sometimes Chunked Transfer Encoding is the reason too.
Related
I just implemented a HTTP Downloader. It has 4 button to do some operation: start, pause, resume, cancel download. When pressing pause or cancel button, I use AsyncTask.cancel() to cancel the download AsyncTask and disable all UI widget temporarily. When AsyncTask onCancelled triggers, I enable the UI widget.
Here's a question: I found inputStram.close() somehow is very slow sometimes. Cause it is called before onCancelled(), it will block UI for a while. I found some article discussed about it but none of their answer really work. It confuses me so bad...
Related questions:
Sometimes HttpURLConnection.getInputStream executes too slowly
InputStream won't close, or takes forever to
Below is my code in AsyncTask. Wish someone give some help. I will appreciate that a lot.
#Override
protected String doInBackground(URL... urls) {
InputStream input = null;
OutputStream output = null;
HttpURLConnection httpURLConnection = null;
try {
URL url = urls[0];
httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setConnectTimeout(CONNECT_TIMEOUT);
httpURLConnection.setInstanceFollowRedirects(true);
httpURLConnection.setRequestProperty("Range", "bytes=" + mDownloadedBytes + "-");
httpURLConnection.setUseCaches(false);
httpURLConnection.setReadTimeout(5000);
httpURLConnection.setRequestProperty("Connection", "close");
System.setProperty("http.keepAlive", "false");
httpURLConnection.connect();
if (!(httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_OK // 200
|| httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_CREATED // 201
|| httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_ACCEPTED // 202
|| httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_NOT_AUTHORITATIVE // 203
|| httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_NO_CONTENT // 204
|| httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_RESET //205
|| httpURLConnection.getResponseCode() == HttpURLConnection.HTTP_PARTIAL)) { //206
return "Download fail, server returned HTTP " + httpURLConnection.getResponseCode()
+ " " + httpURLConnection.getResponseMessage();
}
String fileName = getFileName();
String fileExtension = getFileExtension(httpURLConnection);
if(mDownloadFile == null) {
mDownloadFile = getDownloadFile(fileName, fileExtension);
output = new FileOutputStream(mDownloadFile);
} else {
if(mDownloadFile.exists()) {
output = new FileOutputStream(mDownloadFile, true);
} else {
cancel(true);
return null;
}
}
int fileLength = httpURLConnection.getContentLength();
if(sTotalFileLength == -1 && fileLength != -1){
sTotalFileLength = fileLength;
}
// update download state depending on fileLength
updateUI(fileLength);
// check free space if server respond this value
if(fileLength != -1){
if(!isFreeSpaceEnough(fileLength)){
return "Download fail, you don't have enough free space to save the file";
}
}
// download the file
input = httpURLConnection.getInputStream();
byte data[] = new byte[BUFFER_SIZE];
int count;
while ((count = input.read(data)) != -1) {
if (isCancelled()) {
return null;
}
mDownloadedBytes += count;
if(sTotalFileLength > 0){
int progress = (int)(mDownloadedBytes * 100 / sTotalFileLength);
publishProgress(progress);
}
try {
output.write(data, 0, count);
} catch (IOException e){
return "No enough free space to save file!";
} catch (IndexOutOfBoundsException e){
return "Write to file error";
}
}
// write a record to Download DB after download complete
// just record image in DownloadDb
if(!fileExtension.equals("") && isInImageExtensionList(fileExtension)) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
mDbRow = new DownloadDbRow(dateFormat.format(new Date()), fileName+"."+fileExtension);
mDb.insert(mDbRow);
}
// Tell system to scan for media file change
mMediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
Uri contentUri = Uri.fromFile(mDownloadFile);
mMediaScanIntent.setData(contentUri);
} catch (Exception e) {
return e.toString();
} finally {
try {
if (output != null) {
output.flush();
output.close();
}
/////////////////////
// //
// problems here!! //
// //
/////////////////////
if (input != null) {
input.close();
}
} catch (IOException e) {
return e.toString();
}
if (httpURLConnection != null) {
httpURLConnection.disconnect();
}
}
return DOWNLOAD_SUCCESSFULLY;
}
I want to implement autoupdate for my app.
I used the DownloadManager (and now an AsyncTask for download) and install the file.
The download is working fine. On the PostExecute I fire an intent to install the new apk. Everytime i got a parsing error.
When I open the file in ES File Explorer, I am able to install it successfully, but not within the app and the intent.
I even changed from /Android/data/packagename/files to /Download but still not working.
PS: i know the code is dirty, but working, and I changed so often so many thinks to get it work, but it doesnt...
public class UpdateAsyncTask extends AsyncTask<String, Integer, String>{
#Override
protected void onPreExecute() {
super.onPreExecute();
mProgressDialog = new ProgressDialog(LoginActivity.this);
mProgressDialog.setMessage("A message");
mProgressDialog.setIndeterminate(true);
mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
mProgressDialog.show();
}
#Override
protected void onProgressUpdate(Integer... progress) {
super.onProgressUpdate(progress);
// if we get here, length is known, now set indeterminate to false
mProgressDialog.setIndeterminate(false);
mProgressDialog.setMax(100);
mProgressDialog.setProgress(progress[0]);
}
protected String doInBackground(String... arg0) {
InputStream input = null;
OutputStream output = null;
HttpURLConnection connection = null;
try {
//URL url = new URL(arg0[0]);
URL url = new URL(apkUrl);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
// expect HTTP 200 OK, so we don't mistakenly save error report
// instead of the file
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
return "Server returned HTTP " + connection.getResponseCode() + " " + connection.getResponseMessage();
}
// this will be useful to display download percentage
// might be -1: server did not report the length
int fileLength = connection.getContentLength();
// download the file
input = connection.getInputStream();
//output = new FileOutputStream(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).toString() + "Straffv2.apk");
output = new FileOutputStream("/storage/emulated/0/Download/Straffv2.apk");
File outputFile = new File(Environment.DIRECTORY_DOWNLOADS, "Straffv2.apk");
outputFile.setReadable(true, false);
byte data[] = new byte[4096];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
// allow canceling with back button
if (isCancelled()) {
input.close();
return null;
}
total += count;
// publishing the progress....
if (fileLength > 0) // only if total length is known
publishProgress((int) (total * 100 / fileLength));
output.write(data, 0, count);
}
} catch (Exception e) {
return e.toString();
} finally {
try {
if (output != null)
output.close();
if (input != null)
input.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
}
return null;
}
protected void onPostExecute(String result){
mProgressDialog.dismiss();
if (result != null) {
//Toast.makeText(LoginActivity.this,"Download error: "+result, Toast.LENGTH_LONG).show();
}
else {
//Toast.makeText(LoginActivity.this,"File downloaded", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(Environment.DIRECTORY_DOWNLOADS, "Straffv2.apk")), "application/vnd.android.package-archive");
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); // without this flag android returned a intent error!
LoginActivity.this.startActivity(intent);
}
}
}
protected void doDownload(final String urlLink, final String fileName) {
Thread dx = new Thread() {
public void run() {
File root = android.os.Environment.getExternalStorageDirectory();
File dir = new File (root.getAbsolutePath() + "/Content2/");
if(dir.exists()==false) {
dir.mkdirs();
}
//Save the path as a string value
try
{
URL url = new URL(urlLink);
Log.i("FILE_NAME", "File name is "+imageFile);
Log.i("FILE_URLLINK", "File URL is "+url);
URLConnection connection = url.openConnection();
connection.connect();
// this will be useful so that you can show a typical 0-100% progress bar
int fileLength = connection.getContentLength();
// download the file
InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream(dir+"/"+imageFile);
byte data[] = new byte[1024];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
total += count;
output.write(data, 0, count);
}
output.flush();
output.close();
input.close();
}
catch (Exception e)
{
e.printStackTrace();
Log.i("ERROR ON DOWNLOADING FILES", "ERROR IS" +e);
}
}
};
dx.start();
}
through this, I cannot download the file from the server.
How to solve this problem?
First of all you should use Async-Task.
Here is how you can do this
final DownloadTask downloadTask = new DownloadTask(YourActivity.this);
downloadTask.execute("the url to the file you want to download");
// usually, subclasses of AsyncTask are declared inside the activity class.
// that way, you can easily modify the UI thread from here
private class DownloadTask extends AsyncTask<String, Integer, String> {
private Context context;
public DownloadTask(Context context) {
this.context = context;
}
#Override
protected String doInBackground(String... sUrl) {
InputStream input = null;
OutputStream output = null;
HttpURLConnection connection = null;
try {
URL url = new URL(sUrl[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
// expect HTTP 200 OK, so we don't mistakenly save error report
// instead of the file
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
return "Server returned HTTP " + connection.getResponseCode()
+ " " + connection.getResponseMessage();
}
// this will be useful to display download percentage
// might be -1: server did not report the length
int fileLength = connection.getContentLength();
// download the file
input = connection.getInputStream();
output = new FileOutputStream("/sdcard/file_name.extension");
byte data[] = new byte[4096];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
// allow canceling with back button
if (isCancelled()) {
input.close();
return null;
}
total += count;
}
} catch (Exception e) {
return e.toString();
} finally {
try {
if (output != null)
output.close();
if (input != null)
input.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
}
return null;
}
#Override
protected void onPostExecute(String result) {
if (result != null)
Toast.makeText(context,"Download error: "+result, Toast.LENGTH_LONG).show();
else
Toast.makeText(context,"File downloaded", Toast.LENGTH_SHORT).show();
}
I want to download some files from url to refresh my app but I don´t know what is the best way to do this. I have this code to download one file but when I download more than one sometimes gives me an error. Is it possible to do the download in background without using Android Activity? Thank you
class DownloadTask extends AsyncTask<String, Integer, String> {
private Context context;
private PowerManager.WakeLock mWakeLock;
public DownloadTask(Context context) {
this.context = context;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
// take CPU lock to prevent CPU from going off if the user
// presses the power button during download
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
getClass().getName());
mWakeLock.acquire();
mProgressDialog.show();
}
#Override
protected void onProgressUpdate(Integer... progress) {
super.onProgressUpdate(progress);
// if we get here, length is known, now set indeterminate to false
mProgressDialog.setIndeterminate(false);
mProgressDialog.setMax(100);
mProgressDialog.setProgress(progress[0]);
}
#Override
protected void onPostExecute(String result) {
mWakeLock.release();
mProgressDialog.dismiss();
if (result != null)
Toast.makeText(context,"Error en la descarga: "+result, Toast.LENGTH_LONG).show();
else
Toast.makeText(context,"Programa actualizado correctamente", Toast.LENGTH_LONG).show();
}
#Override
protected String doInBackground(String... sUrl) {
InputStream input = null;
HttpURLConnection connection = null;
try {
URL url = new URL(sUrl[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
// expect HTTP 200 OK, so we don't mistakenly save error report
// instead of the file
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
return "Server returned HTTP " + connection.getResponseCode()
+ " " + connection.getResponseMessage();
}
// this will be useful to display download percentage
// might be -1: server did not report the length
int fileLength = connection.getContentLength();
// download the file
input = connection.getInputStream();
fOut = openFileOutput("example.json",MODE_PRIVATE);
byte data[] = new byte[4096];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
// allow canceling with back button
if (isCancelled()) {
input.close();
return null;
}
total += count;
// publishing the progress....
if (fileLength > 0) // only if total length is known
publishProgress((int) (total * 100 / fileLength));
fOut.write(data, 0, count);
}
} catch (Exception e) {
return e.toString();
} finally {
try {
if (fOut != null)
fOut.close();
if (input != null)
input.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
}
return null;
}
}
and I call to this task with:
downloadTask.execute("myurl");
private class DownloadAsynkTask extends AsyncTask<String, Void, Integer> {
#Override
protected void onPreExecute() {
// progress dialog
}
#Override
protected Integer doInBackground(String... urls) {
HttpURLConnection connection = null;
InputStream is = null;
for (int i=0; i< urls.length; i++) {
try {
URL url = new URL(urls[i]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
return connection.getResponseCode();
} else {
is = connection.getInputStream();
}
// do something whit url data (add it to list maybe)
if (connection != null) {
connection.disconnect();
}
if (is != null) {
is.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return 1;
}
#Override
protected void onPostExecute(Integer result) {
if (result == 1) {
// OK
} else {
}
}
}
and call it whit String[] urls
new DownloadAsynkTask().execute(urls);
public class PreviewDownload extends AsyncTask<String, Void, String> {
public static final String TAG = "PreviewDownload";
public String inputPath = null;
public String outputFolder = null;
public IRIssue issue = null;
#Override
protected String doInBackground(String... parms) {
InputStream input = null;
OutputStream output = null;
HttpURLConnection connection = null;
issue = Broker.model.issueDataStore.getIRIssue(parms[0]);
outputFolder = IRConstant.issueFolder(issue.year, issue.month, issue.day, issue.pubKey);
try {
inputPath = IRConstant.downloadFile(issue.year, issue.month, issue.day, issue.pubKey, "preview", "0");
URL url = new URL(inputPath);
Log.d (TAG,"input: " + inputPath);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
return null;
// return "Server returned HTTP " + connection.getResponseCode()
// + " " + connection.getResponseMessage();
// download the file
input = connection.getInputStream();
output = new FileOutputStream(outputFolder + "/preview.zip");
Log.d (TAG,"output: " + output);
byte data[] = new byte[1024];
int count;
while ((count = input.read(data)) != -1) {
output.write(data, 0, count);
}
} catch (Exception e) {
// return e.toString();
return null;
} finally {
try {
if (output != null)
output.close();
if (input != null)
input.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
}
return outputFolder;
}
#Override
protected void onPostExecute(String outputFolder) {
// TODO Auto-generated method stub
super.onPostExecute(outputFolder);
if (outputFolder != null) {
File zipFile = new File (outputFolder + "/preview.zip");
if (Utils.unzip(outputFolder,outputFolder + "/preview.zip" )) {
zipFile.delete();
issue.isThumbDownloaded = 1;
} else {
issue.isThumbDownloaded = 0;
}
} else {
Toast.makeText(Broker.launcherActivity.getBaseContext(), R.string.wordCantDownload, Toast.LENGTH_LONG).show();
issue.isThumbDownloaded = 0;
}
issue.updateProgress(issue.progress);
}
}
Here is the downloader I implemented , the problem is , when the network lost, the output become null and show error message, however, if I would like to retry two times before showing error message, are there any way to do this? If I perfer not to pass in an object instead of string ,is it not recommended? thanks
What prevents you from re-instanciating and re-executing a "Downloader" from your catch blocks in case of errors ?
You could use a single common shared object between dowloader instances to count the attempts, or better, pass a parameter to each of them. In the catch block, you would then retry if you didn't reach the limit, and increase the value passed to a new downloader... Something recursive.
int expectedLength = connection.getContentLength();
can you compare with the expectedLength & downloaded length and retry?