¿Cómo puedo utilizar una tarea asíncrona para cargar un archivo en el servidor?

 mButton.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { new UploadImageTask().execute(); // initialize asynchronous task }}); //Now implement Asynchronous Task public class Get_User_Data extends AsyncTask<Void, Void, Void> { private final ProgressDialog dialog = new ProgressDialog( MyActivity.this); protected void onPreExecute() { this.dialog.setMessage("Loading..."); this.dialog.setCancelable(false); this.dialog.show(); } @Override protected Void doInBackground(Void... params) { uploadImage(); // inside the method paste your file uploading code return null; } protected void onPostExecute(Void result) { // Here if you wish to do future process for ex. move to another activity do here if (dialog.isShowing()) { dialog.dismiss(); } } } 

Para obtener más información, consulte este enlace http://vikaskanani.wordpress.com/2011/01/29/android-image-upload-activity/

 /** * *******Async Task for Use this UTILITY CLASS * * pass the file which need to upload * * Progress dialog commente/ Uncomment according requirment*******/ private class ImageUploaderTask extends AsyncTask<String, Integer, Void> { @Override protected void onPreExecute(){ // simpleWaitDialog = ProgressDialog.show(BlogPostExamplesActivity.this, "Wait", "Uploading Image"); } @Override protected Void doInBackground(String... params) { new ImageUploadUtility().uploadSingleImage(params[0]); return null; } @Override protected void onPostExecute(Void result){ // simpleWaitDialog.dismiss(); } /** * Method uploads the image using http multipart form data. * We are not using the default httpclient coming with android we are using the new from apache * they are placed in libs folder of the application * * @param imageData * @param filename * @return * @throws Exception */ static boolean doUploadinBackground(final byte[] imageData, String filename) throws Exception{ String responseString = null; PostMethod method; method = new PostMethod("your url to upload"); org.apache.commons.httpclient.HttpClient client = new org.apache.commons.httpclient.HttpClient(); client.getHttpConnectionManager().getParams().setConnectionTimeout( 100000); FilePart photo = new FilePart("userfile", new ByteArrayPartSource( filename, imageData)); photo.setContentType("image/jpeg"); photo.setCharSet(null); String s = new String(imageData); Part[] parts = { new StringPart("latitude", "123456"), new StringPart("longitude","12.123567"), new StringPart("imei","1234567899"), new StringPart("to_email","some email"), photo }; method.setRequestEntity(new MultipartRequestEntity(parts, method .getParams())); client.executeMethod(method); responseString = method.getResponseBodyAsString(); method.releaseConnection(); Log.e("httpPost", "Response status: " + responseString); if (responseString.equals("SUCCESS")) { return true; } else { return false; } } /** * Simple Reads the image file and converts them to Bytes * * @param file name of the file * @return byte array which is converted from the image * @throws IOException */ public static byte[] getBytesFromFile(File file) throws IOException { InputStream is = new FileInputStream(file); // Get the size of the file long length = file.length(); // You cannot create an array using a long type. // It needs to be an int type. // Before converting to an int type, check // to ensure that file is not larger than Integer.MAX_VALUE. if (length > Integer.MAX_VALUE) { // File is too large } // Create the byte array to hold the data byte[] bytes = new byte[(int)length]; // Read in the bytes int offset = 0; int numRead = 0; while (offset < bytes.length && (numRead=is.read(bytes, offset, bytes.length-offset)) >= 0) { offset += numRead; } // Ensure all the bytes have been read in if (offset < bytes.length) { throw new IOException("Could not completely read file "+file.getName()); } // Close the input stream and return bytes is.close(); return bytes; } }