I use AsyncTask with Progress Dialog for downloading a database from a server. I want to provide user with an option of cancellation the downloading task.
My purpose is to dismiss Progress Dialog and cancel AsyncTask when user click on Cancel button on Progress Dialog.
I have applied numerous code examples but they help to dismiss Progress Dialog only and fail to stop or cancel the downloading task.
Regarding my code lines below, can you please give a little help? Many thanks.
EDITED VERSION
public class Download_gram extends Activity {
// File url to download
private static String url = "https://dl.dropbox.com/u/15034088/Anhroid_Dict/grammar.nvk.zip";
private static DownloadFile newTask;
// Progress Dialog
private ProgressDialog progressDialog;
// Progress dialog type (0 - for Horizontal progress bar)
public static final int progress_bar = 0;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.download_gram);
newTask = new DownloadFile();
startDownload_gram = (Button) findViewById(R.id.btnProgressBar_gram);
//start download event and show progress bar
startDownload_gram.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//Checi if file exists
File fgram = new File(Environment.getExternalStorageDirectory()+"/my_Folder/db/my_file/my_file.nvk");
if(fgram.exists())
{
Toast.makeText(getApplicationContext(), "File installed.", Toast.LENGTH_LONG).show();
}
else
{
//checking if the user has an internet connection
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo info = cm.getActiveNetworkInfo();
if (info != null) {
if (!info.isConnected()) {
Toast.makeText(getApplicationContext(), "No Internet connection!", Toast.LENGTH_SHORT).show();
}
// execute async task
else
//new DownloadFile().execute(url);
newTask.execute(url);
}
else {
Toast.makeText(getApplicationContext(), "No Internet connection!", Toast.LENGTH_SHORT).show();
}
}
}});
}
//show progress dialog
#Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case progress_bar:
progressDialog = new ProgressDialog(this);
progressDialog.setMessage("Downloading… Please wait.");
progressDialog.setIndeterminate(false);
progressDialog.setMax(100);
progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressDialog.setCancelable(false);
progressDialog.setButton(DialogInterface.BUTTON_NEGATIVE, "Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dismissDialog(progress_bar);
newTask.cancel(true);
}
});
progressDialog.show();
return progressDialog;
default:
return null;
}
}
//backgroound downloading
class DownloadFile extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
showDialog(progress_bar);
}
#Override
protected String doInBackground(String... args) {
while (url != null) {
int count;
try {
URL url = new URL(args[0]);
URLConnection conection = url.openConnection();
conection.connect();
// getting file length
int fileLength = conection.getContentLength();
InputStream is = new BufferedInputStream(url.openStream(), 8192);
OutputStream os = new FileOutputStream(Environment.getExternalStorageDirectory().getPath() + "/_nvk_gram.zip");
byte data[] = new byte[1024];
long total = 0;
while ((count = is.read(data)) != -1) {
total += count;
publishProgress(""+(int)((total*100)/fileLength));
// writing data to file
os.write(data, 0, count);
}
// flush output
os.flush();
os.close();
is.close();
} catch (Exception e) {
Log.e("Error: ", e.getMessage());
}
//Unzip the downloaded zip file
{
String destinationDirectory = Environment.getExternalStorageDirectory().getPath() + "/my_Folder/db/my_file/";
int BUFFER = 2048;
List<String> zipFiles = new ArrayList<String>();
File sourceZipFile = new File(Environment.getExternalStorageDirectory().getPath() + "/_nvk_gram.zip");
File unzipDestinationDirectory = new File(destinationDirectory);
unzipDestinationDirectory.mkdir();
ZipFile zipFile = null;
// Open Zip file for reading
try {
zipFile = new ZipFile(sourceZipFile, ZipFile.OPEN_READ);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
// Create an enumeration of the entries in the zip file
Enumeration<? extends ZipEntry> zipFileEntries = zipFile.entries();
// Process each entry
while (zipFileEntries.hasMoreElements()) {
// grab a zip file entry
ZipEntry entry = (ZipEntry) zipFileEntries.nextElement();
String currentEntry = entry.getName();
File destFile = new File(unzipDestinationDirectory, currentEntry);
//destFile = new File(unzipDestinationDirectory, destFile.getName());
if (currentEntry.endsWith(".zip")) {
zipFiles.add(destFile.getAbsolutePath());
}
// grab file's parent directory structure
File destinationParent = destFile.getParentFile();
// create the parent directory structure if needed
destinationParent.mkdirs();
try {
// extract file if not a directory
if (!entry.isDirectory()) {
BufferedInputStream is =
new BufferedInputStream(zipFile.getInputStream(entry));
int currentByte;
// establish buffer for writing file
byte data[] = new byte[BUFFER];
// write the current file to disk
FileOutputStream fos = new FileOutputStream(destFile);
BufferedOutputStream dest =
new BufferedOutputStream(fos, BUFFER);
// read and write until last byte is encountered
while ((currentByte = is.read(data, 0, BUFFER)) != -1) {
dest.write(data, 0, currentByte);
}
dest.flush();
dest.close();
is.close();
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
try {
zipFile.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
for (Iterator<String> iter = zipFiles.iterator(); iter.hasNext();) {
String zipName = (String)iter.next();
doUnzip(
zipName,
destinationDirectory +
File.separatorChar +
zipName.substring(0,zipName.lastIndexOf(".zip"))
);
if(isCancelled())return (null);
}
}
}
File fav_ifo = new File(Environment.getExternalStorageDirectory()+"/my_Folder/db/my_file/my_file.nvk");
if(fav_ifo.exists())
{
try {
AssetManager am = getAssets();
String fileName = "my_file.ifo";
File destinationFile = new File(Environment.getExternalStorageDirectory()+"/my_Folder/db/my_file/" + fileName);
InputStream in = am.open("my_file.ifo");
FileOutputStream f = new FileOutputStream(destinationFile);
byte[] buffer = new byte[1024];
int len1 = 0;
while ((len1 = in.read(buffer)) > 0) {
f.write(buffer, 0, len1);
}
f.close();
} catch (Exception e) {
Log.d("CopyFileFromAssetsToSD", e.getMessage());
}
}
else
{
}
//Delete the downloaded zip
File folder = Environment.getExternalStorageDirectory();
String fileName = folder.getPath() + "/_nvk_gram.zip";
File myFile = new File(fileName);
if(myFile.exists())
myFile.delete();
return null;
}
private void doUnzip(String zipName, String string) {
// TODO Auto-generated method stub
}
//updating progress bar
protected void onProgressUpdate(String... progress) {
//progress percentage
progressDialog.setProgress(Integer.parseInt(progress[0]));
}
#Override
protected void onPostExecute(String file_url) {
dismissDialog(progress_bar);
//toast to notify user of download completion
Toast.makeText(getApplicationContext(), "Database successfully downloaded.", Toast.LENGTH_LONG).show();
Intent mainIntent = new Intent(Download_gram.this, my_Main_class.class);
Download_gram.this.startActivity(mainIntent);
}
}
}
see you should keep track of your DownloadFile(aSyncTask) class object.
Create a new variable in your
public class Download_gram extends Activity {
// File url to download
private static String url = "http://www.abc.123.zip";
private static DownloadFile newTask; // ADDED BY ME
// ... ...
you should save the object reference when you call
new DownloadFile().execute("Url String"); //you must be doing this
//instead you should do
newTask = new DownloadFile();
newTask.execute("Url String"); // YOUR OBJECT IS IN newTask
...
// keep track of this newTask variable
// when ever you want to cancel just call
newTask.cancel(true); // ADDED BY ME
dialog.dismiss();//In fact, I want to apply the code to stop both Progress Dialog and AsynTask here.
after setting newTask to cancel, you should check timely in doInBackground that is you task is canceled ? if yes then exit doInBackground
// YOU CAN USE THIS IN WHILE LOOP OF doInBakcground
if(isCancelled())return (null);
//This will exit doInBackground function and hence cancel task.
// you can perform other operations too in this "if" statement as per your need.
for reference of these functions
http://developer.android.com/reference/android/os/AsyncTask.html#cancel(boolean)
##################### New Version ################.
you haven't checked is the task is canceled or not. you have to check everywhere downloading is taking place in asynctask if iscancelled is true return (null); to halt asynctask and stop downloading.
you should replace following code:
while ((count = is.read(data)) != -1) { // inside doInBackground
total += count;
publishProgress(""+(int)((total*100)/fileLength));
// writing data to file
os.write(data, 0, count);
if(isCancelled())return (null); // ADDED BY ME
}
above added line is must this will check if task is canceled this doInBackground function should be over.
You should to
yourAsyncTask.cancel(true);
and, inside your class DownloadFile, you should to check for isCanceled() and do a return if true.
You can do it in this way,
progressDialog.setOnCancelListener(new DialogInterface.OnCancelListener(){
public void onCancel(DialogInterface dialog) {
yourAysncTask.cancel(true);
}
});
Related
In my application, I have an expandablelistview and I want to open a PDF downloaded from the internet when I click on a specific child. The problem is that the pdf file (Read.pdf) is always empty, meaning that the download is not working.
Downloader Class:
public class Downloader {
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();
}
}
Part of the Activity:
private void registerClick() {
expListView.setOnChildClickListener(new OnChildClickListener() {
#Override
public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
if ((groupPosition == 0) && (childPosition == 0)){
File file = new File(Environment.getExternalStorageDirectory()+File.separator+"IAVE", "Read.pdf");
try {
file.createNewFile();
} catch (IOException e1) {
e1.printStackTrace();
}
Downloader.DownloadFile("https://www.cp.pt/StaticFiles/Passageiros/1_horarios/horarios/PDF/lx/linha_cascais.pdf", file);
AbrirPDF.showPdf();
} else {
}
return false;
}
});
}
I think the OpenPDF (AbrirPDF) doesn't have any problem, but I will post it...
public class AbrirPDF {
public static void showPdf()
{
File file = new File(Environment.getExternalStorageDirectory()+File.separator+"IAVE/Read.pdf");
PackageManager packageManager = ContextGetter.getAppContext().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");
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
ContextGetter.getAppContext().startActivity(intent);
}
}
Thank you.
Ideally, your download should happen in a separate thread to avoid locking your app.
Here is an example that also includes a progress bar.
public class MainActivity extends Activity {
private ProgressDialog pDialog;
public static final int progress_bar_type = 0;
private static String file_url = "https://www.cp.pt/StaticFiles/Passageiros/1_horarios/horarios/PDF/lx/linha_cascais.pdf";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new DownloadFileFromURL().execute(file_url);
}
#Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case progress_bar_type: // we set this to 0
pDialog = new ProgressDialog(this);
pDialog.setMessage("Downloading file. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setMax(100);
pDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pDialog.setCancelable(true);
pDialog.show();
return pDialog;
default:
return null;
}
}
class DownloadFileFromURL extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
showDialog(progress_bar_type);
}
#Override
protected String doInBackground(String... f_url) {
int count;
try {
URL url = new URL(f_url[0]);
URLConnection conection = url.openConnection();
conection.connect();
// this will be useful so that you can show a tipical 0-100%
// progress bar
int lenghtOfFile = conection.getContentLength();
// download the file
InputStream input = new BufferedInputStream(url.openStream(),
8192);
// Output stream
OutputStream output = new FileOutputStream(Environment
.getExternalStorageDirectory().toString()
+ "/2011.kml");
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
// publishing the progress....
// After this onProgressUpdate will be called
publishProgress("" + (int) ((total * 100) / lenghtOfFile));
// writing data to file
output.write(data, 0, count);
}
// flushing output
output.flush();
// closing streams
output.close();
input.close();
} catch (Exception e) {
Log.e("Error: ", e.getMessage());
}
return null;
}
protected void onProgressUpdate(String... progress) {
// setting progress percentage
pDialog.setProgress(Integer.parseInt(progress[0]));
}
#Override
protected void onPostExecute(String file_url) {
// dismiss the dialog after the file was downloaded
dismissDialog(progress_bar_type);
}
}
}
I want my program to download many images (around 500) from the internet and store them in my external storage. Currently when I download a single image, it shows a progressBar and downloads the image properly. However when I am trying to replicate w/ two images, it gives the Toast for "Download complete" for both images being downloaded, however no progressBar for either image is shown and only the first image is properly downloaded.
Here is the code for my onCreate method for activity.
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Remove Title bar
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
//force portrait orientation. (No landscape orientation).
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
setContentView(R.layout.activity_quran);
//Instantiate ProgressDialog (Used for downloading quran pages).
myProgressDialog = new ProgressDialog(QuranActivity.this);
myProgressDialog.setMessage("Downloading Quran");
myProgressDialog.setIndeterminate(true);
myProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
myProgressDialog.setCancelable(true);
//execute when the downloader must be fired.
final DownloadTask downloadTask = new DownloadTask(QuranActivity.this);
DownloadTask second = new DownloadTask(getApplicationContext());
myHTTPURL = "https://ia601608.us.archive.org/BookReader/BookReaderImages.php?zip=/10/items/05Quran15LineWhitePageWithVioletBorderWww.Momeen.blogspot.com/05%20Quran%2015%20Line%20[White%20page%20with%20Violet%20border]%20-%20www.Momeen.blogspot.com_jp2.zip&file=05%20Quran%2015%20Line%20[White%20page%20with%20Violet%20border]%20-%20www.Momeen.blogspot.com_jp2/05%20Quran%2015%20Line%20[White%20page%20with%20Violet%20border]%20-%20www.Momeen.blogspot.com_0001.jp2&scale=1&rotate=0";
myHTTPURL2 = "https://ia601608.us.archive.org/BookReader/BookReaderImages.php?zip=/10/items/05Quran15LineWhitePageWithVioletBorderWww.Momeen.blogspot.com/05%20Quran%2015%20Line%20[White%20page%20with%20Violet%20border]%20-%20www.Momeen.blogspot.com_jp2.zip&file=05%20Quran%2015%20Line%20[White%20page%20with%20Violet%20border]%20-%20www.Momeen.blogspot.com_jp2/05%20Quran%2015%20Line%20[White%20page%20with%20Violet%20border]%20-%20www.Momeen.blogspot.com_0002.jp2&scale=1&rotate=0";
//First check if the file has already been created. (Only need to download 1ce, or
//in the case where the user deleted the files, we reinstall them again).
if (isExternalStorageWritable()) {
File makeDirectory = getQuranStorageDir(QuranActivity.this, "Quran_Pages");
for (int i = 0; i < 2; i++) {
Bundle myBundle = new Bundle();
myBundle.putInt("i", i);
if (i == 0) {
downloadTask.execute(myHTTPURL);
try {
downloadTask.get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
myProgressDialog.setOnCancelListener(new DialogInterface.OnCancelListener() {
#Override
public void onCancel(DialogInterface dialog) {
downloadTask.cancel(true);
}
});
} else {
/*if (downloadTask.getStatus() == AsyncTask.Status.FINISHED) {
downloadTask.execute(myHTTPURL2);
} else if (downloadTask.getStatus() == AsyncTask.Status.RUNNING) {
try {
downloadTask.execute(myHTTPURL2).wait(10000);
} catch (InterruptedException e) {
e.printStackTrace();
}
} */
second.execute(myHTTPURL2);
try {
second.get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
// downloadTask.execute(myHTTPURL2);
}
}
}
and this is the code for my AsynTask Class.
#TargetApi(Build.VERSION_CODES.FROYO)
private class DownloadTask extends AsyncTask {
private Context context;
private PowerManager.WakeLock myWakeLock;
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.setDoOutput(true);
connection.setRequestMethod("GET");
connection.connect();
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
return "Server returned HTTP " + connection.getResponseCode()
+ " " + connection.getResponseMessage();
}
//Display download percentage.
int fileLength = connection.getContentLength();
//create folder to place the downloaded file in.
// File Path:E:\Android\data\com.syedabdullah.syed.quran_memorization_application
// \files\Quran Memorization Application\Quran_Pictures
//So first create a root folder Quran Memorization Application then inside that
//folder we create another folder named Quran Pictures.
/* File rootFolder = new File(getExternalFilesDir("Quran Memorization Application"),
"Quran_Pages"); */
//Here we insert inside the Quran_Pictures folder the quran_pages.
//String myFileName = "quran_01.jpg";
Bundle y = new Bundle();
int retrievePos = y.getInt("i");
String quranFilePageName = "_" + retrievePos + ".jpg";
// String fileName = "justwork.jpg";
File sup = new File(getExternalFilesDir("Quran Memorization Application"), "Quran_Pages");
File myFile = new File(sup, quranFilePageName);
myFile.createNewFile();
//downlaod the file.
input = connection.getInputStream();
output = new FileOutputStream(myFile);
byte data[] = new byte[4096];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
//allow cancel with back button.
if (isCancelled()) {
input.close();
return null;
}
total += count;
//publish the progress.
if (fileLength > 0) {
publishProgress((int) (total * 100 / fileLength));
}
output.write(data, 0, count);
}
Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
intent.setData(Uri.fromFile(myFile));
QuranActivity.this.sendBroadcast(intent);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (output != null) {
output.close();
}
if (input != null) {
input.close();
}
} catch (IOException e) {
e.printStackTrace();
}
if (connection != null) {
connection.disconnect();
}
}
return null;
}
#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);
myWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, getClass().getName());
myWakeLock.acquire();
myProgressDialog.show();
}
#Override
protected void onProgressUpdate(Integer... progress) {
super.onProgressUpdate(progress);
//If we get here length is known, so setIndertimante to false.
myProgressDialog.setIndeterminate(false);
myProgressDialog.setMax(100);
myProgressDialog.setProgress(progress[0]);
}
#Override
protected void onPostExecute(String result) {
myWakeLock.release();
myProgressDialog.dismiss();
if (result != null) {
Toast.makeText(context, "Download error: " + result, Toast.LENGTH_LONG).show();
} else {
Toast.makeText(context, "Download Complete", Toast.LENGTH_SHORT).show();
}
}
} }
I was hoping to have a for loop that would create hundreds of downloadTasks and download all the images I need, and then I would call the get method. However in order for that to work, I first need too know why when I try for 2 images only the first one gets downloaded and why no progressbar shows up. Also if possible if I could get a hint as to how I can make my progressBar update for all the images and not be designed for just 1. Thanks in advance. (Note all URLs are currect.)
Thank you so much! figured out that my loops were suppose to go inside doInBackground. Also to anyone else having a similar issue. To download multiple files and display a decent progressBar, here is a very great tutorial: http://theopentutorials.com/tutorials/android/dialog/android-download-multiple-files-showing-progress-bar/
I wrote this code for downloading some files in my android application but now downloaded files are in the root without any special order and it looks very bad! So I want to know how can I add a folder for my application's downloaded files?
A code line to explain the path of output :
OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/" + downloadedfileName);
And here is my code:
private class DownloadFileFromURL extends AsyncTask<String, String, String> {
private String downloadedfileName;
private ProgressDialog pDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
Toast.makeText(getApplicationContext(), "بارگذاری...", Toast.LENGTH_SHORT).show();
pDialog = new ProgressDialog(DownloadActivity.this);
pDialog.setMessage("کتاب در حال بارگذاري، لطفا منتظر بمانيد...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
#Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
pDialog.dismiss();
AlertDialog.Builder builder = new AlertDialog.Builder(DownloadActivity.this)
.setTitle("دانلود کتاب با موفقیت انجام شد")
.setMessage("از دانلود شما سپاسگذاریم.")
.setNeutralButton("خواهش میکنم", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface arg0, int arg1) {
Intent i = new Intent(DownloadActivity.this, LibActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
DownloadActivity.this.startActivity(i);
DownloadActivity.this.finish();
}
});
builder.create().show();
}
public void setDownloadedFileName(String downloadedfileName){
this.downloadedfileName = downloadedfileName;
}
/**
* Downloading file in background thread
* */
#Override
protected String doInBackground(String... surl) {
int count;
try {
URL url = new URL(surl[0]);
URLConnection conection = url.openConnection();
conection.connect();
// this will be useful so that you can show a typical 0-100%
// progress bar
int lenghtOfFile = conection.getContentLength();
// download the file
InputStream input = new BufferedInputStream(url.openStream(),
8192);
// Output stream
//OutputStream output = new FileOutputStream(Environment
// .getExternalStorageDirectory().toString()
// + "/data/" + downloadedfileName);
OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/ketabha/" + downloadedfileName);
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
// publishing the progress....
// After this onProgressUpdate will be called
// publishProgress("" + (int) ((total * 100) / lenghtOfFile));
// writing data to file
output.write(data, 0, count);
}
// flushing output
output.flush();
// closing streams
output.close();
input.close();
} catch (Exception e) {
Log.e("Error: ", e.getMessage());
}
return null;
}
}
Just as simple change this to your favorite directory:
OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/ANYFOLDER/ANOTHERFOLDER/" + downloadedfileName);
And remember that in the first create that directory with this code:
File dir = new File(yourdirectory);
if(!dir.exists()){
dir.mkdirs();
}
Above code work if you added related manifest in your AndroidManifest.xml file:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
and for more information see below links:
How to create directory automatically on SD card
Create folder in Android
can't create a folder in external storage on android device
I am doing a function to download files to android device, works fine but I want to do that if the downloaded file exists already in the device will overwrite it. Here is my code:
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){
this.finish();
}
else
{
Descargar.this.finish();
}
}
#Override
protected String doInBackground(String... sUrl) {
InputStream input = null;
HttpURLConnection connection = null;
for (i=0; i< sUrl.length; i++) {
try {
URL url = new URL(sUrl[i]);
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(i+".json",MODE_PRIVATE);
//fOut = new FileOutputStream("/aste/tiempobilbao.json");
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;
}
}
If the file exist, delete it first.
you can delete file before starting download with below code :
File myFile = new File(fileName);
if(myFile.exists())
myFile.delete();
I'm trying to download a file using an AsyncTask on Android. I want to display a ProgressDialog which should have a progress bar to show the status of the download. I'm using the onProgressUpdate() function for that and implemented a call to publishProgress() in my doInBackground() function. However, the progress dialog only pops up after downloading the file. My code:
protected Long doInBackground(URL...urls) {
for (int i = 0; i < urls.length; i++) {
url = urls[i];
try {
URLConnection conn = url.openConnection();
conn.connect();
totalSize = conn.getContentLength();
BufferedInputStream bis = new BufferedInputStream(url.openStream());
FileOutputStream fos = new FileOutputStream(Environment.getExternalStorageDirectory().getPath() + "/forvo_temp.mp3");
BufferedOutputStream bos = new BufferedOutputStream(fos,1024);
byte [] data = new byte[1024];
int x=0; int c=0;
while((x=bis.read(data,0,1024))>=0){
bos.write(data,0,x);
c += 1024;
publishProgress(c);
}
} catch (Exception e) {
e.printStackTrace();
}
}
return 0L; // Don't know what to do with this
}
protected void onProgressUpdate(Integer...args) {
pd = ProgressDialog.show(context, "Downloading...", "Downloading...", true, false);
pd.setProgress(args[0] / totalSize);
}
I guess the whole file is downloaded when I call new BufferedInputStream(url.openStream()). How can I monitor the download progress?
Wrap URL input stream with you own InputStream that just reads bytes and "monitors" the status, e.g. sends notifications.
It is simple: InputStream is an abstract class with only one abstract method:
public abstract int read() throws IOException;
In your case it should read bytes from stream that it wraps.
public class NotifcationInputStream extends InputStream {
private InputStream in;
private int count;
private Collection<ByteListener> listeners = new ArrayList<ByteListener>();
NotificationInputStream(InputStream in) {
this.in = in;
}
public int read() throws IOException {
int b = in.read();
byteReceived(b);
return b;
}
public void addListener(ByteListener listener) {
listeners.add(listener);
}
private void byteReceived(int b) {
for (ByteListener l : listeners) {
l.byteReceived(b, ++count);
}
}
}
public interface ByteListener extends EventListener {
public void byteReceived(int b, int count);
}
The problem here is how to show the process bar: you have to know total number of bytes. You can get it from HTTP header content-length if your resource is static. Otherwise you need appropriate server support or heuristics.
This code is useful showing download items totol size and downloaded size.
private static final int DOWNLOAD_ONPROGRESS = 1;
#Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case DOWNLOAD_ONPROGRESS:
progressDialog = new ProgressDialog(this);
progressDialog.setMessage("Downloading latest ...");
progressDialog.setCancelable(true);
progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
try {
progressDialog.show();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return progressDialog;
default:
return null;
}
}
You can use AsyncTask for downloading the version in background.
private class DownLoad extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
logger.info("LoadDataAsync onPreExecute");
showDialog(DOWNLOAD_ONPROGRESS);
}
#Override
protected String doInBackground(String... aurl) {
int count = 0;
try {
URL url = new URL(aurl[0]);
URLConnection urlConnection = url.openConnection();
urlConnection.connect();
int contentlength = urlConnection.getContentLength();
progressDialog.setMax(contentlength);
String PATH = "";
File file = null;
if (android.os.Environment.getExternalStorageState().equals(
android.os.Environment.MEDIA_MOUNTED)) {
PATH = Environment.getExternalStorageDirectory()
+ "/download/";
file = new File(PATH);
file.mkdirs();
File outputFile = new File(file, "telfaz.apk");
OutputStream fos = new FileOutputStream(outputFile);
InputStream is = new BufferedInputStream(url.openStream());
byte[] buffer = new byte[1024];
long len1 = 0;
while ((count = is.read(buffer)) != -1
&& !downLoad.isCancelled()) {
len1 += count;
publishProgress("" + len1);
fos.write(buffer, 0, count);
}
fos.flush();
fos.close();
is.close();
}
logger.info("Success -> file downloaded succesfully. returning 'success' code");
return Util.APK_DOWNLOAD_SUCCESS;
} catch (IOException e) {
logger.error("Exception in update process : "
+ Util.getStackTrace(e));
}
logger.info("Failed -> file download failed. returning 'error' code");
return Util.APK_DOWNLOAD_FAILED;
}
#Override
protected void onPostExecute(String result) {
logger.info("on DownLoad onPostExecute. result : " + result);
progressDialog.dismiss();
removeDialog(DOWNLOAD_ONPROGRESS);
if (result.equalsIgnoreCase(Util.APK_DOWNLOAD_SUCCESS)) {
Update();
} else {
Toast.makeText(DownloadAllContentsActivity.this,
getString(R.string.updateApplicationFailed),
Toast.LENGTH_LONG).show();
loadDataAsync.execute();
}
}
#Override
protected void onProgressUpdate(String... values) {
if (values != null && values.length > 0) {
progressDialog.setProgress(Integer.parseInt(values[0]));
}
}
}