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POProgressDialog in AsyncTask throwing a NullPointerException?
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  1. POProgressDialog in AsyncTask throwing a NullPointerException?
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    copied!<p>I'm trying to display a <code>ProgressDialog</code> while loading a <code>json</code> feed from a http server. I get a <code>NullPointerException</code> in <code>doInBackground</code> and <code>onPostExecute</code>. If I have not misunderstood <code>AsyncTask</code>, in <code>onPostExecute</code> the final code will run! Where is my fault? Here's my activity code:</p> <pre><code>public class ResultInput extends Activity { int count = 0; String mainUrl; String[] product_pict_part; InputStream is = null; private ProgressDialog pd; String TAG = "meinDebug"; ParseEan parse_code; String readProductNameEan; ImageView productPic; String productName; Drawable drawable; TextView product_name; TextView text_level; int productLevel; private Context context; // private MyProgressDialog dialog; @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); new ProgressTask(ResultInput.this).execute(); } private InputStream fetch(String urlString) throws MalformedURLException, IOException { DefaultHttpClient httpClient = new DefaultHttpClient(); HttpGet request = new HttpGet(urlString); HttpResponse response = httpClient.execute(request); return response.getEntity().getContent(); } private class ProgressTask extends AsyncTask&lt;String, Void, Boolean&gt; { private ProgressDialog dialog; private Activity activity; // private List&lt;Message&gt; messages; public ProgressTask(Activity activity) { this.activity = activity; context = activity; dialog = new ProgressDialog(context); } /** progress dialog to show user that the backup is processing. */ /** application context. */ protected void onPreExecute() { this.dialog.setMessage("Progress start"); this.dialog.show(); } @Override protected void onPostExecute(final Boolean success) { pd.dismiss(); productPic.setImageDrawable(drawable); Log.i(TAG, "Picture URL " + mainUrl); product_name.setText(productName); if (productLevel == 1) { text_level.setText("helal"); } else if (productLevel == 2) { text_level.setText("mittel"); } else if (productLevel == 3) { text_level.setText("haram"); } else if (productLevel == 4) { text_level.setText("in analyse"); } if (dialog.isShowing()) { dialog.dismiss(); } if (success) { Toast.makeText(context, "OK", Toast.LENGTH_LONG).show(); } else { Toast.makeText(context, "Error", Toast.LENGTH_LONG).show(); } } protected Boolean doInBackground(final String... args) { try { mainUrl = "http://nur-efsan.de/websHalalCheck/public/image/index/dir/"; product_name = (TextView) findViewById(R.id.produkt_name); text_level = (TextView) findViewById(R.id.text_level); productPic = (ImageView) findViewById(R.id.productpic); productName = parse_code.parseJSONPost("data", "name", readProductNameEan); String productPicture = parse_code.parseJSONPost("data", "image", readProductNameEan); productLevel = Integer.parseInt(parse_code.parseJSONPost( "data", "levelId", readProductNameEan)); product_pict_part = productPicture.split("/"); mainUrl = mainUrl + product_pict_part[0] + "/name/" + product_pict_part[1]; try { is = fetch(mainUrl); } catch (MalformedURLException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } drawable = Drawable.createFromStream(is, "src"); return true; } catch (Exception e) { Log.e("tag", "error", e); return false; } } } } </code></pre>
 

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