my AsyncCode and Service code is running fine, but when i merge them together it crashes my application's GUI, the code manages to write to the database.
I am new to android development so i do not quite know why it crashes.
This is my code for the method
#Override
public void onStart(Intent intent, int startId) {
// TODO Auto-generated method stub
super.onStart(intent, startId);
Log.e("<<myServiceRunner-onStart>>", "I am alive-3!");
Thread triggerService = new Thread(new Runnable(){
String msg = "message";
long startingTime = System.currentTimeMillis();
long tics = 0;
#Override
public void run() {
// TODO Auto-generated method stub
for (int i = 0; (i < 120) & isRunning; i++) {
try {
tics = System.currentTimeMillis() - startingTime;
Intent myFilterResponse = new Intent("liren.action.GOSERVICE3");
//WIFI METHOD START
mainWifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
registerReceiver(new BroadcastReceiver()
{
#Override
public void onReceive(Context c, Intent intent)
{
results = mainWifi.getScanResults();
size = results.size();
ScanResult bestSignal = null;
for (ScanResult result : results) {
if (bestSignal == null
|| WifiManager.compareSignalLevel(bestSignal.level, result.level) < 0)
{
bestSignal = result;
}
}
msg = tics + " Strongest Network: " + bestSignal.SSID + " - Signal Strength:" + bestSignal.level;
new sendPostData().execute(Integer.toString(bestSignal.level) ,bestSignal.SSID.toString());
}
}, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
mainWifi.startScan();
//WIFI METHOD END
myFilterResponse.putExtra("serviceData", msg);
sendBroadcast(myFilterResponse);
Thread.sleep(1000);
} catch (Exception e){
e.printStackTrace();
}
}
}});
triggerService.start();
}
private class sendPostData extends AsyncTask<String, Void, String>
{
#Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
HttpPost request = new HttpPost(SERVICE_URI + "/StrongestWifi");
request.setHeader("Accept", "application/json");
request.setHeader("Content-type", "application/json");
JSONStringer getWifiInfo;
try {
getWifiInfo = new JSONStringer()
.object()
.key("myWifiClass")
.object()
.key("SignalStrength").value(params[0])
.key("SSID").value(params[1])
.endObject()
.endObject();
StringEntity entity = new StringEntity(getWifiInfo.toString());
request.setEntity(entity);
// Send request to WCF service
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpResponse response = httpClient.execute(request);
Log.d("WebInvoke", "Saving : " + response.getStatusLine().getStatusCode());
}
catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
}
}
And here is my log cat:
>06-02 09:58:42.112: E/<<myServiceRunner-onStart>>(21871): I am alive-3!
>06-02 09:58:42.151: E/MAIN>>>(21871): message - receiving data 179736967
>06-02 09:58:42.252: E/SpannableStringBuilder(21871): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
>06-02 09:58:42.260: E/SpannableStringBuilder(21871): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
>06-02 09:58:42.276: E/SpannableStringBuilder(21871): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
>06-02 09:58:42.276: E/SpannableStringBuilder(21871): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
>06-02 09:58:43.127: W/dalvikvm(21871): threadid=18: thread exiting with uncaught exception (group=0x40d09930)
>06-02 09:58:43.135: E/MAIN>>>(21871): 2 Strongest Network: Chiameng - Signal Strength:-69 - receiving data 179737949
>06-02 09:58:43.166: E/AndroidRuntime(21871): FATAL EXCEPTION: AsyncTask #5
>06-02 09:58:43.166: E/AndroidRuntime(21871): java.lang.RuntimeException: An error occured while executing doInBackground()
>06-02 09:58:43.166: E/AndroidRuntime(21871): at android.os.AsyncTask$3.done(AsyncTask.java:299)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.util.concurrent.FutureTask.run(FutureTask.java:239)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.lang.Thread.run(Thread.java:856)
>06-02 09:58:43.166: E/AndroidRuntime(21871): Caused by: java.lang.IllegalArgumentException: Illegal character in scheme at index 0: 192.168.1.64:4567/AllocationService.svc/StrongestWifi
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.net.URI.create(URI.java:727)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at org.apache.http.client.methods.HttpPost.<init>(HttpPost.java:79)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at com.example.pcsprojectnetworkcodes.myServiceRunner$sendPostData.doInBackground(myServiceRunner.java:118)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at com.example.pcsprojectnetworkcodes.myServiceRunner$sendPostData.doInBackground(myServiceRunner.java:1)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at android.os.AsyncTask$2.call(AsyncTask.java:287)
>06-02 09:58:43.166: E/AndroidRuntime(21871): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
>06-02 09:58:43.166: E/AndroidRuntime(21871): ... 4 more
>06-02 09:58:44.166: E/MAIN>>>(21871): 2 Strongest Network: Chiameng - Signal Strength:-69 - receiving data 179738981
>06-02 09:58:44.409: W/dalvikvm(21871): threadid=12: thread exiting with uncaught exception (group=0x40d09930)
>06-02 09:58:44.409: I/Process(21871): Sending signal. PID: 21871 SIG: 9
There is a probleme with your SERVICE_URI variable. Maybe a misplaced space.
Or maybe you have forgotten the "http://" (or equivalent) at the beginning...
There seems to be a problem here:
Illegal character in scheme at index 0
which refers to this line here:
HttpPost request = new HttpPost(SERVICE_URI + "/StrongestWifi");
Most likely you have a space at the beginning of the SERVICE_URI?
I would bet that you have a space (' ') in front of the URL that you're passing:
192.168.1.64:4567/AllocationService.svc/StrongestWifi
Double-check that. You might just need to do a String#trim() on the URL.
In Your Async Task you should have Return type of doInBackground and postExecute must be same . And You are return null that why it give you error
Related
I have created an application containing image to video maker and i using MediaMuxer to creating video from sequence of images but SlideEncoder add second image to auto close MediaMuxer and application is crush.
05-22 07:58:33.691 6091-6122/com.aspiration.imagetovideomaker E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #2
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:299)
at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
at java.util.concurrent.FutureTask.run(FutureTask.java:137)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
at java.lang.Thread.run(Thread.java:856)
Caused by: java.lang.IllegalStateException
at android.media.MediaCodec.native_configure(Native Method)
at android.media.MediaCodec.configure(MediaCodec.java:257)
at com.aspiration.imagetovideomaker.encoding.SlideEncoder.prepareEncoder(SlideEncoder.java:57)
at com.aspiration.imagetovideomaker.ImageToVideo$EncodingTask.doInBackground(ImageToVideo.java:221)
at com.aspiration.imagetovideomaker.ImageToVideo$EncodingTask.doInBackground(ImageToVideo.java:205)
at android.os.AsyncTask$2.call(AsyncTask.java:287)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
at java.util.concurrent.FutureTask.run(FutureTask.java:137)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
at java.lang.Thread.run(Thread.java:856)
here my video creation code:
SlideEncoder slideEncoder = new SlideEncoder();
try {
slideEncoder.prepareEncoder(outputFile);
Bitmap prevBm = null;
dialog.setMax(MyApplication.bitmapList.size());
for (int idx = 0; idx < MyApplication.bitmapList.size(); idx++) {
publishProgress(String.valueOf(idx + 1));
SlideShow.init();
if (idx > 0) prevBm = MyApplication.bitmapList.get(idx - 1);
Bitmap curBm = MyApplication.bitmapList.get(idx);
for (int i = 0; i < (MyApplication.FRAME_PER_SEC * MyApplication.SLIDE_TIME); i++) {
// Drain any data from the encoder into the muxer.
slideEncoder.drainEncoder(false);
// Generate a frame and submit it.
slideEncoder.generateFrame(curBm, curBm);
//slideEncoder.generateFrame(prevBm, curBm);
}
}
slideEncoder.drainEncoder(true);
} catch (IOException e) {
e.printStackTrace();
} finally {
slideEncoder.releaseEncoder();
}
here my prepareEncoder
public void prepareEncoder(File outputFile) throws IOException {
mBufferInfo = new MediaCodec.BufferInfo();
try {
MediaFormat format = MediaFormat.createVideoFormat(MIME_TYPE, WIDTH, HEIGHT);
format.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
format.setInteger(MediaFormat.KEY_BIT_RATE, MyApplication.BIT_RATE);
format.setInteger(MediaFormat.KEY_FRAME_RATE, MyApplication.FRAME_PER_SEC);
format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, IFRAME_INTERVAL);
mEncoder = MediaCodec.createEncoderByType(MIME_TYPE);
mEncoder.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
mInputSurface = mEncoder.createInputSurface();
mEncoder.start();
mMuxer = new MediaMuxer(outputFile.getPath().toString(), MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
mTrackIndex = -1;
mMuxerStarted = false;
} catch (Exception e) {
e.printStackTrace();
Log.e("SlideEncoder", e.toString());
}
}
I got this error whenever I change my URL to my online hosting, but if I change to 10.0.2.2 everything seems fine and running.
LogCat
02-01 23:02:18.302 17643-18052/com.example.jithea.testlogin E/JSON Parser﹕ Error parsing data org.json.JSONException: Value <br><table of type java.lang.String cannot be converted to JSONObject
02-01 23:02:18.303 17643-18052/com.example.jithea.testlogin W/dalvikvm﹕ threadid=12: thread exiting with uncaught exception (group=0x40d8d9a8)
02-01 23:02:18.303 17643-18052/com.example.jithea.testlogin W/dalvikvm﹕ threadid=12: uncaught exception occurred
02-01 23:02:18.304 17643-18052/com.example.jithea.testlogin W/System.err﹕ java.lang.RuntimeException: An error occured while executing doInBackground()
02-01 23:02:18.304 17643-18052/com.example.jithea.testlogin W/System.err﹕ at android.os.AsyncTask$3.done(AsyncTask.java:299)
02-01 23:02:18.304 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
02-01 23:02:18.305 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
02-01 23:02:18.305 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:239)
02-01 23:02:18.305 17643-18052/com.example.jithea.testlogin W/System.err﹕ at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
02-01 23:02:18.305 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
02-01 23:02:18.306 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
02-01 23:02:18.306 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.lang.Thread.run(Thread.java:838)
02-01 23:02:18.306 17643-18052/com.example.jithea.testlogin W/System.err﹕ Caused by: java.lang.NullPointerException
02-01 23:02:18.306 17643-18052/com.example.jithea.testlogin W/System.err﹕ at com.example.jithea.testlogin.NewsActivity$LoadAllProducts.doInBackground(NewsActivity.java:132)
02-01 23:02:18.306 17643-18052/com.example.jithea.testlogin W/System.err﹕ at com.example.jithea.testlogin.NewsActivity$LoadAllProducts.doInBackground(NewsActivity.java:107)
02-01 23:02:18.307 17643-18052/com.example.jithea.testlogin W/System.err﹕ at android.os.AsyncTask$2.call(AsyncTask.java:287)
02-01 23:02:18.307 17643-18052/com.example.jithea.testlogin W/System.err﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:234)
02-01 23:02:18.307 17643-18052/com.example.jithea.testlogin W/System.err﹕ ... 4 more
02-01 23:02:18.307 17643-18052/com.example.jithea.testlogin W/dalvikvm﹕ threadid=12: calling UncaughtExceptionHandler
02-01 23:02:18.315 17643-18052/com.example.jithea.testlogin E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:299)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
at java.util.concurrent.FutureTask.run(FutureTask.java:239)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:838)
Caused by: java.lang.NullPointerException
at com.example.jithea.testlogin.NewsActivity$LoadAllProducts.doInBackground(NewsActivity.java:132)
at com.example.jithea.testlogin.NewsActivity$LoadAllProducts.doInBackground(NewsActivity.java:107)
at android.os.AsyncTask$2.call(AsyncTask.java:287)
at java.util.concurrent.FutureTask.run(FutureTask.java:234)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:838)
02-01 23:02:18.371 17643-17659/com.example.jithea.testlogin I/SurfaceTextureClient﹕ [STC::queueBuffer] (this:0x528dc150) fps:43.08, dur:1044.57, max:73.51, min:6.02
And here's my NewsActivity.java
public class NewsActivity extends ListActivity {
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParserNews jParser = new JSONParserNews();
ArrayList<HashMap<String, String>> productsList;
// url to get all products list
private static String url_all_products = "http://agustiniancampusevents.site40.net/newsDB/get_all_news.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_NEWS = "news";
private static final String TAG_PID = "pid";
private static final String TAG_NEWSTITLE = "newstitle";
// products JSONArray
JSONArray products = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_news);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
// Loading products in Background Thread
new LoadAllProducts().execute();
// Get listview
ListView lv = getListView();
// on seleting single product
// launching Edit Product Screen
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
String pid = ((TextView) view.findViewById(R.id.pid)).getText()
.toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(),
ViewNewsActivity.class);
// sending pid to next activity
in.putExtra(TAG_PID, pid);
// starting new activity and expecting some response back
startActivityForResult(in, 100);
}
});
}
// Response from Edit Product Activity
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// if result code 100
if (resultCode == 100) {
// if result code 100 is received
// means user edited/deleted product
// reload this screen again
Intent intent = getIntent();
finish();
startActivity(intent);
}
}
/**
* Background Async Task to Load all product by making HTTP Request
*/
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
*/
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(NewsActivity.this);
pDialog.setMessage("Loading products. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
/**
* getting All products from url
*/
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Products: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
products = json.getJSONArray(TAG_NEWS);
// looping through All Products
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_PID);
String newstitle = c.getString(TAG_NEWSTITLE);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_PID, id);
map.put(TAG_NEWSTITLE, newstitle);
// adding HashList to ArrayList
productsList.add(map);
}
} else {
// no products found
// Launch Add New product Activity
Intent i = new Intent(getApplicationContext(),
ViewNewsActivity.class);
// Closing all previous activities
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(i);
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* *
*/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting all products
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
NewsActivity.this, productsList,
R.layout.news_list_item, new String[]{TAG_PID,
TAG_NEWSTITLE},
new int[]{R.id.pid, R.id.newstitle});
// updating listview
setListAdapter(adapter);
}
});
}
}
}
It reads image from the channel and write it to card. the image in card is completely written and is fine. The only problem is thread in hanged and does not execute any line after that loop.
protected Bitmap doInBackground(String... arg0) {
// TODO Auto-generated method stub'
// Runtime.getRuntime().availableProcessors();
System.out.println("Inside doinback"+ RemoteScreen.out.toString());
try {
RemoteScreen.out.write(210);
//Home.threadloop = false;
Bitmap bitmap = null;
String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = "a.png";
String imageInSD = baseDir + File.separator + fileName;
System.out.println(imageInSD);
if (is!= null) {
FileOutputStream fos = null;
BufferedOutputStream bos = null;
try {
// Log.i("IMSERVICE", "FILERECCC-1");
//ContextWrapper context = null;
fos = new FileOutputStream(imageInSD);
bos = new BufferedOutputStream(fos);
byte[] aByte = new byte[1024];
int bytesRead;
//thread stuck in this loop and does not move forward
while ( (bytesRead = is.read(aByte)) > 0 ) {
if (bytesRead == 1)
break;
bos.write(aByte, 0, bytesRead);
System.out.println("Loop"+aByte);
}
bos.close();
Log.i("IMSERVICE", "out of loop");
java.io.FileInputStream in = new FileInputStream(imageInSD);
bitmap = BitmapFactory.decodeStream(in);
bitmap = BitmapFactory.decodeFile(imageInSD);
Log.i("IMSERVICE", "saved");
if (bitmap != null)
System.out.println(bitmap.toString());
} catch (IOException ex) {
// Do exception handling
// Log.i("IMSERVICE", "exception ");
}
}
publishProgress(b);
b = null;
ch = 4646;
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
log trace shows following error.
05-10 20:34:42.715: E/AndroidRuntime(1135): FATAL EXCEPTION: AsyncTask #3
05-10 20:34:42.715: E/AndroidRuntime(1135): java.lang.RuntimeException: An error occured while executing doInBackground()
05-10 20:34:42.715: E/AndroidRuntime(1135): at android.os.AsyncTask$3.done(AsyncTask.java:299)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.util.concurrent.FutureTask.run(FutureTask.java:239)
05-10 20:34:42.715: E/AndroidRuntime(1135): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.lang.Thread.run(Thread.java:856)
05-10 20:34:42.715: E/AndroidRuntime(1135): Caused by: java.lang.NullPointerException
05-10 20:34:42.715: E/AndroidRuntime(1135): at com.rms.remotedesktop1.screencahnge.doInBackground(screencahnge.java:43)
05-10 20:34:42.715: E/AndroidRuntime(1135): at com.rms.remotedesktop1.screencahnge.doInBackground(screencahnge.java:1)
05-10 20:34:42.715: E/AndroidRuntime(1135): at android.os.AsyncTask$2.call(AsyncTask.java:287)
05-10 20:34:42.715: E/AndroidRuntime(1135): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
According to the logcat, the code is crashing at line 43 with a Null Pointer Exception, and I can't tell which line 43 is. However:
Have you checked that Environment.getExternalStorageDirectory().getAbsolutePath() is returning non null? It maybe that there is no external storage directory, or you don't have permission to know about it.
It is also worth reading the developer pages, http://developer.android.com/reference/android/os/Environment.html#getExternalStorageDirectory(), which note that you shouldn't write to that directory, which you seem to be doing.
I solved this problem by myself. There was error in static variable who was changing his value due to logical error in code.
Hi, I try to check network connectivity and Internet present by using following method
check = new ConnectionDetector(getApplicationContext());
conn = check.isConnectingToInternet();
public class ConnectionDetector {
private Context _context;
public ConnectionDetector(Context context){
this._context = context;
}
/**
* Checking for all possible internet providers
* **/
/*public boolean isConnectingToInternet(){
ConnectivityManager connectivity = (ConnectivityManager) _context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity != null)
{
NetworkInfo[] info = connectivity.getAllNetworkInfo();
if (info != null)
for (int i = 0; i < info.length; i++)
if (info[i].getState() == NetworkInfo.State.CONNECTED)
{
return true;
}
}
return false;
}*/
public boolean isConnectingToInternet(){
try{
ConnectivityManager cm = (ConnectivityManager)_context.getSystemService
(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
Log.d("NetInfo", String.valueOf(netInfo));
if (netInfo != null && netInfo.isConnected())
{
//Network is available but check if we can get access from the network.
URL url = new URL("http://www.Google.com/");
HttpURLConnection urlc = (HttpURLConnection) url.openConnection();
urlc.setRequestProperty("Connection", "close");
urlc.setConnectTimeout(2000); // Timeout 2 seconds.
urlc.connect();
Log.d("NetInfo Response Code", String.valueOf(urlc.getResponseCode()));
// Toast.makeText(getApplicationContext(), String.valueOf(urlc.getResponseCode()), Toast.LENGTH_LONG).show();
if (urlc.getResponseCode() == 200) //Successful response.
{
return true;
}
else
{
Log.d("NO INTERNET", "NO INTERNET");
return false;
}
}
}
catch(Exception e)
{
e.printStackTrace();
}
return false;
}
}
Note :
But this will return NetworkOnMainThread Exception like follows.kindly any one suggest me what mistakes i made.......
03-27 12:53:35.617: W/System.err(1095): android.os.NetworkOnMainThreadException
03-27 12:53:35.627: W/System.err(1095): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1084)
03-27 12:53:35.637: W/System.err(1095): at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
03-27 12:53:35.637: W/System.err(1095): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
03-27 12:53:35.647: W/System.err(1095): at java.net.InetAddress.getAllByName(InetAddress.java:220)
03-27 12:53:35.647: W/System.err(1095): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:71)
03-27 12:53:35.657: W/System.err(1095): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
03-27 12:53:35.668: W/System.err(1095): at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
03-27 12:53:35.668: W/System.err(1095): at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
03-27 12:53:35.677: W/System.err(1095): at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
03-27 12:53:35.687: W/System.err(1095): at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
03-27 12:53:35.699: W/System.err(1095): at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
03-27 12:53:35.699: W/System.err(1095): at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
03-27 12:53:35.707: W/System.err(1095): at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
03-27 12:53:35.718: W/System.err(1095): at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
03-27 12:53:35.727: W/System.err(1095): at com.slet.routemytrips.beta.ConnectionDetector.isConnectingToInternet(ConnectionDetector.java:50)
03-27 12:53:35.727: W/System.err(1095): at com.slet.routemytrips.beta.Disclaimer$1.onClick(Disclaimer.java:178)
03-27 12:53:35.738: W/System.err(1095): at android.view.View.performClick(View.java:3480)
03-27 12:53:35.738: W/System.err(1095): at android.view.View$PerformClick.run(View.java:13983)
03-27 12:53:35.748: W/System.err(1095): at android.os.Handler.handleCallback(Handler.java:605)
03-27 12:53:35.757: W/System.err(1095): at android.os.Handler.dispatchMessage(Handler.java:92)
03-27 12:53:35.757: W/System.err(1095): at android.os.Looper.loop(Looper.java:137)
03-27 12:53:35.767: W/System.err(1095): at android.app.ActivityThread.main(ActivityThread.java:4340)
03-27 12:53:35.777: W/System.err(1095): at java.lang.reflect.Method.invokeNative(Native Method)
03-27 12:53:35.777: W/System.err(1095): at java.lang.reflect.Method.invoke(Method.java:511)
03-27 12:53:35.787: W/System.err(1095): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
03-27 12:53:35.797: W/System.err(1095): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
03-27 12:53:35.807: W/System.err(1095): at dalvik.system.NativeStart.main(Native Method)
03-27 12:57:05.237: D/dalvikvm(90): GC_CONCURRENT freed 666K, 10% free 12624K/14023K, paused 6ms+10ms
You can't make HTTP requests on the main thread, it would cause the UI to freeze up. So it throws that exception. You need to do it in an AsyncTask or another Thread.
http://developer.android.com/reference/android/os/NetworkOnMainThreadException.html
NetworkOnMainThreadException is thrown if you attempt to make a network request in the main UI Thread. So all network related operation should be done on the background thread.
AsyncTask is designed to be a helper class around Thread and Handler and does not constitute a generic threading framework. AsyncTasks should ideally be used for short operations (a few seconds at the most.) If you need to keep threads running for long periods of time, it is highly recommended you use the various APIs provided by the java.util.concurrent pacakge such as Executor, ThreadPoolExecutor and FutureTask.
http://developer.android.com/reference/android/os/AsyncTask.html
class TheTask extends AsyncTask<Void,Void,Void>
{
protected void onPreExecute()
{ super.onPreExecute();
//display progressdialog.
}
protected void doInBackground(Void ...params)
{
//http request. do not update ui here
return null;
}
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
//dismiss progressdialog.
//update ui
}
}
An alternative to asynctask is Robospice. Can make multiple spice request. Notifies on the ui thread. https://github.com/octo-online/robospice
To check Netowrk Connectivity.
In your activity
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
if(CheckNetwork.isInternetAvailable(MainActivity.this))
{
//call asyntask and make http request.
}
}
CheckNetwork class
public class CheckNetwork {
private static final String TAG = CheckNetwork.class.getSimpleName();
public static boolean isInternetAvailable(Context context)
{
NetworkInfo info = (NetworkInfo) ((ConnectivityManager)
context.getSystemService(Context.CONNECTIVITY_SERVICE)).getActiveNetworkInfo();
if (info == null)
{
Log.d(TAG,"no internet connection");
return false;
}
else
{
if(info.isConnected())
{
Log.d(TAG," internet connection available...");
return true;
}
else
{
Log.d(TAG," internet connection");
return true;
}
}
}
}
I am creating an RSS reader application for android 4.0+. I have put the reader code in AsyncTask because of the NetworkOnMainThreadException. The code almost works fine, however one line has an error. This is my code:
Java code:
private class PostTask extends AsyncTask<String, Integer, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(String... params) {
String url=params[0];
headlines = new ArrayList();
links = new ArrayList();
//Download and parse xml feed
headlines = new ArrayList();
links = new ArrayList();
try {
URL url1 = new URL("http://feeds.pcworld.com/pcworld/latestnews");
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(false);
XmlPullParser xpp = factory.newPullParser();
// We will get the XML from an input stream
xpp.setInput(getInputStream(url1), "UTF_8");
/* We will parse the XML content looking for the "<title>" tag which appears inside the "<item>" tag.
* However, we should take in consideration that the rss feed name also is enclosed in a "<title>" tag.
* As we know, every feed begins with these lines: "<channel><title>Feed_Name</title>...."
* so we should skip the "<title>" tag which is a child of "<channel>" tag,
* and take in consideration only "<title>" tag which is a child of "<item>"
*
* In order to achieve this, we will make use of a boolean variable.
*/
boolean insideItem = false;
// Returns the type of current event: START_TAG, END_TAG, etc..
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_TAG) {
if (xpp.getName().equalsIgnoreCase("item")) {
insideItem = true;
} else if (xpp.getName().equalsIgnoreCase("title")) {
if (insideItem)
headlines.add(xpp.nextText()); //extract the headline
} else if (xpp.getName().equalsIgnoreCase("link")) {
if (insideItem)
links.add(xpp.nextText()); //extract the link of article
}
}else if(eventType==XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")){
insideItem=false;
}
eventType = xpp.next(); //move to next element
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return "Feed parsed!";
}
#Override
protected void onProgressUpdate(Integer... values) {
super.onProgressUpdate(values);
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
// Binding data
ArrayAdapter adapter = new ArrayAdapter(this,
android.R.layout.simple_list_item_1, headlines);
setListAdapter(adapter);
}
}
in this code snippet i get an error:
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
// Binding data
ArrayAdapter adapter = new ArrayAdapter(this,
android.R.layout.simple_list_item_1, headlines);
setListAdapter(adapter);
}
Error: The constructor ArrayAdapter(MainActivity.PostTask, int, List) is undefined.
Logcat:
01-26 20:55:53.811: E/AndroidRuntime(1830): FATAL EXCEPTION: AsyncTask #1
01-26 20:55:53.811: E/AndroidRuntime(1830): java.lang.RuntimeException: An error occured while executing doInBackground()
01-26 20:55:53.811: E/AndroidRuntime(1830): at android.os.AsyncTask$3.done(AsyncTask.java:278)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
01-26 20:55:53.811: E/AndroidRuntime(1830): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.lang.Thread.run(Thread.java:856)
01-26 20:55:53.811: E/AndroidRuntime(1830): Caused by: java.lang.IllegalArgumentException
01-26 20:55:53.811: E/AndroidRuntime(1830): at org.kxml2.io.KXmlParser.setInput(KXmlParser.java:1615)
01-26 20:55:53.811: E/AndroidRuntime(1830): at com.mysoftware.mysoftwareos.mobile.MainActivity$PostTask.doInBackground(MainActivity.java:343)
01-26 20:55:53.811: E/AndroidRuntime(1830): at com.mysoftware.mysoftwareos.mobile.MainActivity$PostTask.doInBackground(MainActivity.java:1)
01-26 20:55:53.811: E/AndroidRuntime(1830): at android.os.AsyncTask$2.call(AsyncTask.java:264)
01-26 20:55:53.811: E/AndroidRuntime(1830): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
01-26 20:55:53.811: E/AndroidRuntime(1830): ... 5 more
Could anyone please look into my problem and come up with a solution? Or tell me if i should do anything different? Thanks a lot!
Change it to:
ArrayAdapter adapter = new ArrayAdapter(MainActivity.this,
android.R.layout.simple_list_item_1, headlines);
this refers to the AsyncTask, so you have to explicitly reference MainActivity's this.
use Activity Context instead of AsyncTask to Create ArrayAdapter inside onPostExecute method as :
ArrayAdapter<String> adapter =
new ArrayAdapter<String>(Your_Current_Activity.this,
android.R.layout.simple_list_item_1, headlines);
setListAdapter(adapter);
EDIT :
after log posted also change
xpp.setInput(getInputStream(url1), "UTF_8");
to
xpp.setInput(url1.openConnection().getInputStream(), "UTF_8");