I am trying to range beacons and I am doing exactly what it is written here:
http://altbeacon.github.io/android-beacon-library/samples.html
didRangeBeaconsInRegion method is firing but always with empty collection.
I have installed "locate" by altbeacon and it located 3 beacons.
this is my code: am I missing something?
public class BeaconSingletone implements BeaconConsumer {
private static BeaconSingletone instance;
private final org.altbeacon.beacon.BeaconManager beaconManager2;
private ArrayList<BeaconThin> listNearBeacons = new ArrayList<>();
BeaconRegion region = new BeaconRegion("ranged region",
UUID.fromString("B9407F30-F5F8-466E-AFF9-25556B57FE6D"), null, null);
private List<EventInterface> listeners = new ArrayList<EventInterface>();
private BeaconSingletone()
{
beaconManager2 = org.altbeacon.beacon.BeaconManager.getInstanceForApplication(ar_activity.get());
// To detect proprietary beacons, you must add a line like below corresponding to your beacon
// type. Do a web search for "setBeaconLayout" to get the proper expression.
beaconManager2.getBeaconParsers().add(new BeaconParser().
setBeaconLayout("m:2-3=beac,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25"));
beaconManager2.bind(this);
public static BeaconSingletone getInstance() {
if(instance == null) {
instance = new BeaconSingletone();
}
return instance;
}
private void showNotification(Region region, final List<Beacon> list) {
listNearBeacons.clear();
listNearBeacons.add(new BeaconThin(3514,7580,-1));
for (Iterator<EventInterface> i = listeners.iterator(); i.hasNext(); ) {
EventInterface item = i.next();
//item.NewBeaconFound(list.get(0).getMajor(),list.get(0).getMinor(),Utils.computeAccuracy(list.get(0)));
item.NewBeaconsFound(listNearBeacons);
}
return;
}
#Override
public void onBeaconServiceConnect() {
beaconManager2.addRangeNotifier(new RangeNotifier() {
#Override
public void didRangeBeaconsInRegion(Collection<org.altbeacon.beacon.Beacon> beacons, org.altbeacon.beacon.Region region) {
if (beacons.size() > 0) {
Log.i("BeaconManager", "The first beacon I see is about "+beacons.iterator().next().getDistance()+" meters away.");
}
}
});
try {
beaconManager2.startRangingBeaconsInRegion(new org.altbeacon.beacon.Region("mybeacons", null, null, null));
} catch (RemoteException e) { }{
}
}
#Override
public Context getApplicationContext() {
return ar_activity.get();
}
#Override
public void unbindService(ServiceConnection serviceConnection) {
ar_activity.get().unbindService(serviceConnection);
}
#Override
public boolean bindService(Intent intent, ServiceConnection serviceConnection, int i) {
return ar_activity.get().bindService(intent, serviceConnection, i);
}
}
You need to add a beacon layout for the beacon type you are using (iBeacon?). Replace this line:
beaconManager2.getBeaconParsers().add(new BeaconParser().
setBeaconLayout("m:2-3=beac,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25"));
With the proper layout from here:
https://beaconlayout.wordpress.com
Related
This Is Main Fragment
Fragment:
private void getStock() {
dialog.show();
Retrofit retrofit = RetrofitClient.getRetrofitInstance();
apiInterface api = retrofit.create(apiInterface.class);
Call<List<Blocks>>call = api.getVaccineBlocks();
call.enqueue(new Callback<List<Blocks>>() {
#Override
public void onResponse(Call<List<Blocks>>call, Response<List<Blocks>> response) {
if (response.code() == 200) {
block = response.body();
spinnerada();
dialog.cancel();
}else{
dialog.cancel();
}
}
#Override
public void onFailure(Call<List<Blocks>> call, Throwable t) {
dialog.cancel();
}
});
}
private void spinnerada() {
String[] s = new String[block.size()];
for (int i = 0; i < block.size(); i++) {
s[i] = block.get(i).getBlockName();
final ArrayAdapter a = new ArrayAdapter(getContext(), android.R.layout.simple_spinner_item, s);
a.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
//Setting the ArrayAdapter data on the Spinner
spinner.setAdapter(a);
}
}
This Is Blocks Model
model:
package com.smmtn.book.models;
import java.io.Serializable;
public class Blocks implements Serializable {
public String id;
public String blockName;
public String blockSlug;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getBlockName() {
return blockName;
}
public void setBlockName(String blockName) {
this.blockName = blockName;
}
public String getBlockSlug() {
return blockSlug;
}
public void setBlockSlug(String blockSlug) {
this.blockSlug = blockSlug;
}
}
here i need onitemclick with blockslug please any one can help, am new to android so i need some example.when on click i want take blockslug and load another method with that blockslug,like will get data from u "http://example.com/block/"+blockslug
i want to get blockslug from selected block
i hope guys i will get help
and sorry for my bad English,
First of all, you need to implement setOnItemSelectedListener. Refer to this https://stackoverflow.com/a/20151596/9346054
Once you selected the item, you can call them by making a new method. Example like below
public void onItemSelected(AdapterView<?> parent, View view, int pos,long id) {
Toast.makeText(parent.getContext(),
"OnItemSelectedListener : " + parent.getItemAtPosition(pos).toString(),
Toast.LENGTH_SHORT).show();
final String itemSelected = parent.getItemAtPosition(pos).toString();
showBlockSlug(itemSelected);
}
And then, at the method showBlockSlug() , you can call Retrofit.
private void showBlockSlug(final String blockslug){
final String url = "http://example.com/block/"+ blockslug;
//Do your stuff...
}
I've installed the PocketSphinx demo and it works fine under Ubuntu and Eclipse, but despite trying I can't work out how I would add recognition of multiple words.
All I want is for the code to recognize single words, which I can then switch() within the code, e.g. "up", "down", "left", "right". I don't want to recognize sentences, just single words.
Any help on this would be grateful. I have spotted other users' having similar problems but nobody knows the answer so far.
One thing which is baffling me is why do we need to use the "wakeup" constant at all?
private static final String KWS_SEARCH = "wakeup";
private static final String KEYPHRASE = "oh mighty computer";
.
.
.
recognizer.addKeyphraseSearch(KWS_SEARCH, KEYPHRASE);
What has wakeup got to do with anything?
I have made some progress (?) : Using addGrammarSearch I am able to use a .gram file to list my words, e.g. up,down,left,right,forwards,backwards, which seems to work well if all I say are those particular words. However, any other words will cause the system to match what is said to the "nearest" word from those stated. Ideally I don't want recognition to occur if words spoken are not in the .gram file...
Thanks to Nikolay's tip (see his answer above), I have developed the following code which works fine, and does not recognize words unless they're on the list. You can copy and paste this directly over the main class in the PocketSphinxDemo code:
public class PocketSphinxActivity extends Activity implements RecognitionListener
{
private static final String DIGITS_SEARCH = "digits";
private SpeechRecognizer recognizer;
#Override
public void onCreate(Bundle state)
{
super.onCreate(state);
setContentView(R.layout.main);
((TextView) findViewById(R.id.caption_text)).setText("Preparing the recognizer");
try
{
Assets assets = new Assets(PocketSphinxActivity.this);
File assetDir = assets.syncAssets();
setupRecognizer(assetDir);
}
catch (IOException e)
{
// oops
}
((TextView) findViewById(R.id.caption_text)).setText("Say up, down, left, right, forwards, backwards");
reset();
}
#Override
public void onPartialResult(Hypothesis hypothesis)
{
}
#Override
public void onResult(Hypothesis hypothesis)
{
((TextView) findViewById(R.id.result_text)).setText("");
if (hypothesis != null)
{
String text = hypothesis.getHypstr();
makeText(getApplicationContext(), text, Toast.LENGTH_SHORT).show();
}
}
#Override
public void onBeginningOfSpeech()
{
}
#Override
public void onEndOfSpeech()
{
reset();
}
private void setupRecognizer(File assetsDir)
{
File modelsDir = new File(assetsDir, "models");
recognizer = defaultSetup().setAcousticModel(new File(modelsDir, "hmm/en-us-semi"))
.setDictionary(new File(modelsDir, "dict/cmu07a.dic"))
.setRawLogDir(assetsDir).setKeywordThreshold(1e-20f)
.getRecognizer();
recognizer.addListener(this);
File digitsGrammar = new File(modelsDir, "grammar/digits.gram");
recognizer.addKeywordSearch(DIGITS_SEARCH, digitsGrammar);
}
private void reset()
{
recognizer.stop();
recognizer.startListening(DIGITS_SEARCH);
}
}
Your digits.gram file should be something like:
up /1e-1/
down /1e-1/
left /1e-1/
right /1e-1/
forwards /1e-1/
backwards /1e-1/
You should experiment with the thresholds within the double slashes // for performance, where 1e-1 represents 0.1 (I think). I think the maximum is 1.0.
And it's 5.30pm so I can stop working now. Result.
you can use addKeywordSearch which uses to file with keyphrases. One phrase per line with threshold for each phrase in //, for example
up /1.0/
down /1.0/
left /1.0/
right /1.0/
forwards /1e-1/
Threshold must be selected to avoid false alarms.
Working on updating Antinous amendment to the PocketSphinx demo to allow it to run on Android Studio. This is what I have so far,
//Note: change MainActivity to PocketSphinxActivity for demo use...
public class MainActivity extends Activity implements RecognitionListener {
private static final String DIGITS_SEARCH = "digits";
private SpeechRecognizer recognizer;
/* Used to handle permission request */
private static final int PERMISSIONS_REQUEST_RECORD_AUDIO = 1;
#Override
public void onCreate(Bundle state) {
super.onCreate(state);
setContentView(R.layout.main);
((TextView) findViewById(R.id.caption_text))
.setText("Preparing the recognizer");
// Check if user has given permission to record audio
int permissionCheck = ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.RECORD_AUDIO);
if (permissionCheck != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.RECORD_AUDIO}, PERMISSIONS_REQUEST_RECORD_AUDIO);
return;
}
new AsyncTask<Void, Void, Exception>() {
#Override
protected Exception doInBackground(Void... params) {
try {
Assets assets = new Assets(MainActivity.this);
File assetDir = assets.syncAssets();
setupRecognizer(assetDir);
} catch (IOException e) {
return e;
}
return null;
}
#Override
protected void onPostExecute(Exception result) {
if (result != null) {
((TextView) findViewById(R.id.caption_text))
.setText("Failed to init recognizer " + result);
} else {
reset();
}
}
}.execute();
((TextView) findViewById(R.id.caption_text)).setText("Say one, two, three, four, five, six...");
}
/**
* In partial result we get quick updates about current hypothesis. In
* keyword spotting mode we can react here, in other modes we need to wait
* for final result in onResult.
*/
#Override
public void onPartialResult(Hypothesis hypothesis) {
if (hypothesis == null) {
return;
} else if (hypothesis != null) {
if (recognizer != null) {
//recognizer.rapidSphinxPartialResult(hypothesis.getHypstr());
String text = hypothesis.getHypstr();
if (text.equals(DIGITS_SEARCH)) {
recognizer.cancel();
performAction();
recognizer.startListening(DIGITS_SEARCH);
}else{
//Toast.makeText(getApplicationContext(),"Partial result = " +text,Toast.LENGTH_SHORT).show();
}
}
}
}
#Override
public void onResult(Hypothesis hypothesis) {
((TextView) findViewById(R.id.result_text)).setText("");
if (hypothesis != null) {
String text = hypothesis.getHypstr();
makeText(getApplicationContext(), "Hypothesis" +text, Toast.LENGTH_SHORT).show();
}else if(hypothesis == null){
makeText(getApplicationContext(), "hypothesis = null", Toast.LENGTH_SHORT).show();
}
}
#Override
public void onDestroy() {
super.onDestroy();
recognizer.cancel();
recognizer.shutdown();
}
#Override
public void onBeginningOfSpeech() {
}
#Override
public void onEndOfSpeech() {
reset();
}
#Override
public void onTimeout() {
}
private void setupRecognizer(File assetsDir) throws IOException {
// The recognizer can be configured to perform multiple searches
// of different kind and switch between them
recognizer = defaultSetup()
.setAcousticModel(new File(assetsDir, "en-us-ptm"))
.setDictionary(new File(assetsDir, "cmudict-en-us.dict"))
// .setRawLogDir(assetsDir).setKeywordThreshold(1e-20f)
.getRecognizer();
recognizer.addListener(this);
File digitsGrammar = new File(assetsDir, "digits.gram");
recognizer.addKeywordSearch(DIGITS_SEARCH, digitsGrammar);
}
private void reset(){
recognizer.stop();
recognizer.startListening(DIGITS_SEARCH);
}
#Override
public void onError(Exception error) {
((TextView) findViewById(R.id.caption_text)).setText(error.getMessage());
}
public void performAction() {
// do here whatever you want
makeText(getApplicationContext(), "performAction done... ", Toast.LENGTH_SHORT).show();
}
}
Caveat emptor: this is a work in progress. Check back later. Suggestions would be appreciated.
My unit of work class is mentioned below and I am using Ninject and I have tried injecting IUnitOfWork per request per thread scope, transient etc. but I am still getting error which is:
"Message":"An error has occurred.","ExceptionMessage":"The context cannot be used while the model is being created. This exception may be thrown if the context is used inside the OnModelCreating method or if the same context instance is accessed by multiple threads concurrently. Note that instance members of DbContext and related classes are not guaranteed to be thread safe.","ExceptionType":"System.InvalidOperationException
I get this error when i make two web API (get) calls at the same time using angularJS and it shows error at the point _context.Set<TEntity>().FirstOrDefault(match);
public class UnitOfWork : IUnitOfWork, IDisposable
{
private My_PromotoolEntities _uowDbContext = new My_PromotoolEntities();
private Dictionary<string, object> _repositories;
// Do it like this if no specific class file
private GenericRepository<MysPerson> _personRepository;
//private GenericRepository<MysDataSource> dataSourcesRepository;
//private GenericRepository<MysCountry> countryMasterRepository;
// Or like this if with specific class file.
private DataSourceRepository _dataSourcesRepository;
private CustomerRepository _customerRepository;
private DeviceRepository _deviceRepository;
private DeviceRegistrationRepository _deviceRegistrationRepository;
private EmailQueueRepository _emailQueueRepository;
public void SetContext(My_PromotoolEntities context)
{
_uowDbContext = context;
}
public void CacheThis(object cacheThis, string keyName, TimeSpan howLong)
{
Cacheing.StaticData.CacheStaticData(cacheThis, keyName, howLong);
}
public object GetFromCache(string keyName)
{
return Cacheing.StaticData.GetFromCache(keyName);
}
public GenericRepository<T> GenericRepository<T>() where T : BaseEntity
{
if (_repositories == null)
{
_repositories = new Dictionary<string, object>();
}
var type = typeof(T).Name;
if (!_repositories.ContainsKey(type))
{
var repositoryType = typeof(GenericRepository<>);
var repositoryInstance = Activator.CreateInstance(repositoryType.MakeGenericType(typeof(T)), _uowDbContext);
_repositories.Add(type, repositoryInstance);
}
return (GenericRepository<T>)_repositories[type];
}
public GenericRepository<MysPerson> PersonRepository
{
get
{
if (this._personRepository == null)
{
this._personRepository = new GenericRepository<MysPerson>(_uowDbContext);
}
return _personRepository;
}
}
public DataSourceRepository DataSourcesRepository
{
get
{
if (this._dataSourcesRepository == null)
{
this._dataSourcesRepository = new DataSourceRepository(_uowDbContext);
}
return _dataSourcesRepository;
}
}
public CustomerRepository CustomerRepository
{
get
{
if (this._customerRepository == null)
{
this._customerRepository = new CustomerRepository(_uowDbContext);
}
return _customerRepository;
}
}
public DeviceRepository DeviceRepository
{
get
{
if (this._deviceRepository == null)
{
this._deviceRepository = new DeviceRepository(_uowDbContext);
}
return _deviceRepository;
}
}
public DeviceRegistrationRepository DeviceRegistrationRepository
{
get
{
if (this._deviceRegistrationRepository == null)
{
this._deviceRegistrationRepository = new DeviceRegistrationRepository(_uowDbContext);
}
return _deviceRegistrationRepository;
}
}
public EmailQueueRepository emailQueueRepository
{
get
{
if (this._emailQueueRepository == null)
{
this._emailQueueRepository = new EmailQueueRepository(_uowDbContext);
}
return _emailQueueRepository;
}
}
/// <summary>
/// Commits all changes to the db. Throws exception if fails. Call should be in a try..catch.
/// </summary>
public void Save()
{
try
{
_uowDbContext.SaveChanges();
}
catch (DbEntityValidationException dbevex)
{
// Entity Framework specific errors:
StringBuilder sb = new StringBuilder();
var eve = GetValidationErrors();
if (eve.Count() > 0)
{
eve.ForEach(error => sb.AppendLine(error));
}
ClearContext();
// Throw a new exception with original as inner.
var ex = new Exception(sb.ToString(), dbevex);
ex.Source = "DbEntityValidationException";
throw ex;
}
catch (Exception)
{
ClearContext();
throw;
}
}
private void ClearContext()
{
DetachAll();
}
private void DetachAll()
{
foreach (DbEntityEntry dbEntityEntry in _uowDbContext.ChangeTracker.Entries())
{
if (dbEntityEntry.Entity != null)
{
dbEntityEntry.State = EntityState.Detached;
}
}
}
/// <summary>
/// Checks for EF DbEntityValidationException(s).
/// </summary>
/// <returns>Returns a List of string containing the EF DbEntityValidationException(s).</returns>
public List<string> GetValidationErrors()
{
if (_uowDbContext.GetValidationErrors().Count() != 0)
{
return _uowDbContext.GetValidationErrors().Select(e => string.Join(Environment.NewLine, e.ValidationErrors.Select(v => string.Format("{0} - {1}", v.PropertyName, v.ErrorMessage)))).ToList();
}
return null;
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
_uowDbContext.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
You should never use a context in 2 places at the same time, that's exactly why you are getting this error. From the MSDN documentation:
Thread Safety: Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
It is a little hard to make suggestions without a repro but there is a brute force approach that should resolve the issue. If you have an interception point before/during DI setup then you can cause all the context initialization etc to happen by creating an instance of your context and calling ctx.Database.Initialize(force: false); Passing 'force: false' will ensure that the initialization still only happens once per AppDomain
Am a little stuck with getting changes reflected from the ViewModel to the View when used in a MvxBindableTableViewCell. I am using the vNext branch of MvvmCross on iOS.
Everything is set up properly and the initial values are visible when loading/showing the list for the first time. The list is a ObservableCollection<T> and the ViewModels inherit from MvxViewModel (thus implements INotifyPropertyChanged).
The main ViewModel looks like this:
public abstract class BaseViewModel : MvxViewModel, IMvxServiceConsumer
{
//... just regular implementation
}
public class UploadListViewModel: BaseViewModel
{
private readonly IUploadItemTasks uploadItemTasks;
private readonly IPhotoPickerService photoPickerService;
public IObservableCollection<UploadItemViewModel> Uploads { get { return this.LoadUploadItems(); } }
public UploadListViewModel()
{
this.uploadItemTasks = this.GetService<IUploadItemTasks>();
this.photoPickerService = this.GetService<IPhotoPickerService>();
}
private IObservableCollection<UploadItemViewModel> LoadUploadItems()
{
using (var unitOfWork = UnitOfWork.Start ())
{
return new SimpleObservableCollection<UploadItemViewModel>(uploadItemTasks.GetAll());
}
}
public void StartUpload ()
{
if (this.Uploads == null || this.Uploads.Count == 0) {
ReportError("Error", "No images to upload");
return;
}
this.Uploads.ForEach (uploadItem => PostCallback (uploadItem));
}
private void PostCallback (UploadItemViewModel uploadAsset)
{
IProgressReporter progressReporter = uploadAsset;
this.photoPickerService.GetAssetFullImage(uploadAsset.ImageUrl,
(image) => {
UIImage fullImage = image;
NSData jpeg = fullImage.AsJPEG();
byte[] jpegBytes = new byte[jpeg.Length];
System.Runtime.InteropServices.Marshal.Copy(jpeg.Bytes, jpegBytes, 0, Convert.ToInt32(jpeg.Length));
MemoryStream stream = new MemoryStream(jpegBytes);
Uri destinationUrl = new Uri(uploadAsset.DestinationUrl + "&name=" + uploadAsset.Name + "&contentType=image%2FJPEG");
//TO DO: Move this to plugin
var uploader = new Uploader().UploadPicture (destinationUrl, stream, UploadComplete, progressReporter);
uploader.Host = uploadAsset.Host;
ThreadPool.QueueUserWorkItem (delegate {
uploader.Upload ();
jpeg = null;
});
});
}
private void UploadComplete (string name)
{
if (name == null){
ReportError("Error","There was an error uploading the media.");
} else
{
//ReportError("Succes", name);
}
}
The item ViewModel looks like:
public interface IProgressReporter
{
float Progress { get; set;}
}
public abstract class BaseAssetViewModel: BaseViewModel, IBaseAssetViewModel
{
//... just regular properties
}
public class UploadItemViewModel: BaseAssetViewModel, IProgressReporter
{
public UploadItemViewModel(): base()
{
}
private float progress;
public float Progress {
get {
return this.progress;
}
set {
this.progress = value;
this.RaisePropertyChanged(() => Progress);
}
}
}
The View for the items inherits from MvxBindableTableViewCell and has the property:
private float progress;
public float ProgressMarker {
get {
return progress;
}
set {
progress = value;
// change progressbar or textfield here
}
}
The tableviewcell is bounded to the UploadItemViewModel via the BindingText:
public const string BindingText = #"ProgressMarker Progress, Converter=Float;";
The Uploader class mentioned in the snippet of UploadListViewModel implements a private method which tries to set the progress on the IProgressReporter.
float progressValue;
void SetProgress (float newvalue)
{
progressValue = newvalue;
this.dispatcher.InvokeOnMainThread (delegate {
if (ProgressReporter != null)
ProgressReporter.Progress = progressValue;
});
}
During the first viewing of the list I can see that the properties in both the ViewModel and View are being hit but when I update the ViewModel via the interface IProgressReporter with a new value in Progress the View in the tableviewcell is not updated nor the property is being called.
What am I doing wrong or what am I missing here?
UPDATE: Check the answer to this question.
I found why the binding didn't work. I was replacing the ObservableCollection over and over again.. I changed that piece of code as stated below and now it reflects the changes made to the UploadItemViewModel in the View of the cell.
private IObservableCollection<UploadItemViewModel> uploads;
private IObservableCollection<UploadItemViewModel> LoadUploadItems()
{
if (uploads == null)
{
using (var unitOfWork = UnitOfWork.Start ())
{
uploads = new SimpleObservableCollection<UploadItemViewModel>(uploadItemTasks.FindAll());
}
}
return uploads;
}
How can I cancel a thread from another class fetching/refreshing location. I am able to cancel a thread from within the same class. But I am unable to do this across classes. Declaring the GPSThread static did not help. Can anyone please guide?
Class1:
public class GPSListener {
/* Other instantiation code */
Dialog busyDialog1 = new Dialog("Refreshing Location...",
new String [] { "Cancel" },
new int [] { Dialog.CANCEL},
Dialog.CANCEL,
Bitmap.getPredefinedBitmap(Bitmap.HOURGLASS))
{
public void fieldChanged(Field field1, int context1)
{
GPSHandler.requestStop();
busyDialog1.cancel();
}
};
public String refreshCoordinates() {
String test = "nothing";
if (GPSHandler.isStopRequested())
{
GPSHandler.stopRequested = false;
return null;
}
GPSHandler.getInstance().setListener(this);
GPSHandler.getInstance().requestLocationUpdates();
if (GPSHandler.isStopRequested())
{
GPSHandler.stopRequested = false;
return null;
}
busyDialog1.setEscapeEnabled(false);
busyDialog1.show();
return test;
}
public void onLocationReceived(Coordinates location) {
lblLatitude.setText(Double.toString(location.getLatitude()));
lblLongitude.setText(Double.toString(location.getLongitude()));
busyDialog1.cancel();
}
}
Class 2:
public class GPSHandler {
private GPSThread _gpsThread;
private Coordinates _location;
private boolean _gotLocation;
private GPSListener _listener;
/** this class will be a Singleton, as the device only has one GPS system */
private static GPSHandler _instance;
/** #return the Singleton instance of the GPSHandler */
public static GPSHandler getInstance() {
if (_instance == null) {
_instance = new GPSHandler();
}
return _instance;
}
public static boolean stopRequested = false;
public synchronized static void requestStop() {
stopRequested = true;
}
public synchronized static boolean isStopRequested() {
return stopRequested;
}
/** not publicly accessible ... use getInstance() */
private GPSHandler() {
}
/** call this to trigger a new location fix */
public void requestLocationUpdates() {
if (_gpsThread == null || !_gpsThread.isAlive()) {
_gpsThread = new GPSThread();
_gpsThread.start();
}
}
public void setListener(GPSListener listener) {
// only supports one listener this way
_listener = listener;
}
private void setLocation(final Coordinates value) {
_location = value;
if (value.getLatitude() != 0.0 || value.getLongitude() != 0.0) {
_gotLocation = true;
if (_listener != null) {
// this assumes listeners are UI listeners, and want callbacks on the UI thread:
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
_listener.onLocationReceived(value);
}
});
}
}
}
private class GPSThread extends Thread {
private void getLocationFromGoogle() {
try {
int cellID = GPRSInfo.getCellInfo().getCellId();
int lac = GPRSInfo.getCellInfo().getLAC();
String urlString2 = "http://www.google.com/glm/mmap";
// Open a connection to Google Maps API
ConnectionFactory connFact = new ConnectionFactory();
ConnectionDescriptor connDesc;
connDesc = connFact.getConnection(urlString2);
HttpConnection httpConn2;
httpConn2 = (HttpConnection)connDesc.getConnection();
httpConn2.setRequestMethod("POST");
// Write some custom data to Google Maps API
OutputStream outputStream2 = httpConn2.openOutputStream();//getOutputStream();
writeDataGoogleMaps(outputStream2, cellID, lac);
// Get the response
InputStream inputStream2 = httpConn2.openInputStream();//getInputStream();
DataInputStream dataInputStream2 = new DataInputStream(inputStream2);
// Interpret the response obtained
dataInputStream2.readShort();
dataInputStream2.readByte();
final int code = dataInputStream2.readInt();
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
Dialog.alert(code + "");
}
});
if (code == 0) {
final double latitude = dataInputStream2.readInt() / 1000000D;
final double longitude = dataInputStream2.readInt() / 1000000D;
setLocation(new Coordinates(latitude, longitude, 0.0f));
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
Dialog.alert(latitude+"-----"+longitude);
}
});
dataInputStream2.readInt();
dataInputStream2.readInt();
dataInputStream2.readUTF();
} else {
System.out.println("Error obtaining Cell Id ");
}
outputStream2.close();
inputStream2.close();
} catch (Exception e) {
System.out.println("Error: " + e.getMessage());
}
}
private void tryGetLocationFromDevice() {
_gotLocation = false;
try {
Criteria myCriteria = new Criteria();
myCriteria.setCostAllowed(false);
LocationProvider myLocationProvider = LocationProvider.getInstance(myCriteria);
try {
Location myLocation = myLocationProvider.getLocation(300);
setLocation(myLocation.getQualifiedCoordinates());
} catch ( InterruptedException iex ) {
System.out.println(iex.getMessage());
} catch ( LocationException lex ) {
System.out.println(lex.getMessage());
}
} catch ( LocationException lex ) {
System.out.println(lex.getMessage());
}
if (!_gotLocation) {
getLocationFromGoogle();
}
}
public void run() {
int bbMapsHandle = CodeModuleManager.getModuleHandle("net_rim_bb_lbs"); // OS 4.5 - 6.0
int bbMapsHandle60 = CodeModuleManager.getModuleHandle("net_rim_bb_maps"); // OS 6.0
if (bbMapsHandle > 0 || bbMapsHandle60 > 0) {
tryGetLocationFromDevice();
} else {
getLocationFromGoogle();
}
}
}
private void writeDataGoogleMaps(OutputStream out, int cellID, int lac) throws IOException {
DataOutputStream dataOutputStream = new DataOutputStream(out);
dataOutputStream.writeShort(21);
dataOutputStream.writeLong(0);
dataOutputStream.writeUTF("en");
dataOutputStream.writeUTF("Android");
dataOutputStream.writeUTF("1.0");
dataOutputStream.writeUTF("Web");
dataOutputStream.writeByte(27);
dataOutputStream.writeInt(0);
dataOutputStream.writeInt(0);
dataOutputStream.writeInt(3);
dataOutputStream.writeUTF("");
dataOutputStream.writeInt(cellID);
dataOutputStream.writeInt(lac);
dataOutputStream.writeInt(0);
dataOutputStream.writeInt(0);
dataOutputStream.writeInt(0);
dataOutputStream.writeInt(0);
dataOutputStream.flush();
}
}
Your GPSThread object is currently declared as a private inner class within GPSHandler. If you want to stop execution (or indeed do anything with it) from outside the scope of GPSHandler you will need to mark it as public. You will also need to provide some public mechanism (e.g. a stop() method) to cancel the thread execution.
The most common way of doing this is to have a boolean flag inside your thread (e.g shouldStop) which is checked within your main execution loop inside run() to see if it should stop. When the stop() method is called shouldStop is set to true and your Thread will stop.
Here's a good example: How to stop threads in Java?
There's two groups of changes you should make.
Change the Stop Requested Flag
First, remember that encapsulation is a good thing in Object-Oriented languages. The isStopRequested() method, or stopRequested variable of the GPSHandler should not be used outside of that class. Your UI's GPSListener should not attempt to use either of those. I would change your GPSHandler to use this:
private static boolean stopRequested = false;
public synchronized static void requestStop() {
stopRequested = true;
}
private synchronized static boolean isStopRequested() {
return stopRequested;
}
Only requestStop() should be public. It looks like you made stopRequested public to allow the GPSListener to reset it. If it needs resetting, let the class that owns that variable do the resetting. For example, in GPSHandler:
/** call this to trigger a new location fix */
public void requestLocationUpdates() {
if (_gpsThread == null || !_gpsThread.isAlive()) {
// reset this stop flag:
stopRequested = false;
_gpsThread = new GPSThread();
_gpsThread.start();
}
}
requestLocationUpdates() is really the method that starts the thread, so it should be where stopRequested gets reset to false.
Also, another reason that you should not make stopRequested public and allow other classes to use it is that this is not generally thread-safe. One of the reasons to wrap stopRequested with the requestStop() and isStopRequested() methods is to add thread-safety. There's many ways to do that, but those two methods achieve thread-safety by being marked with the synchronized keyword.
Change How/Where You Check the Flag
After you make these fixes, you need to change where you check if a stop has been requested. You don't really want to check isStopRequested() in the refreshCoordinates() method. That method involves almost no work. Even though it starts the process of getting a location fix, that only starts a thread, but the actual work of getting the location is done on a background thread (your GPSThread). If requestStop() is called, it's very unlikely that it will be called in the middle of refreshCoordinates(), so that's not where you should check it.
Check isStopRequested() multiple times within the GPSHandler class's methods tryGetLocationFromDevice() and getLocationFromGoogle(). Those are the methods that perform slow processing. Those are the ones you might want to interrupt in the middle. So, something like this:
private void getLocationFromGoogle() {
try {
int cellID = GPRSInfo.getCellInfo().getCellId();
int lac = GPRSInfo.getCellInfo().getLAC();
String urlString2 = "http://www.google.com/glm/mmap";
if (isStopRequested()) return;
// Open a connection to Google Maps API
ConnectionFactory connFact = new ConnectionFactory();
ConnectionDescriptor connDesc;
connDesc = connFact.getConnection(urlString2);
HttpConnection httpConn2;
httpConn2 = (HttpConnection)connDesc.getConnection();
httpConn2.setRequestMethod("POST");
// Write some custom data to Google Maps API
OutputStream outputStream2 = httpConn2.openOutputStream();//getOutputStream();
writeDataGoogleMaps(outputStream2, cellID, lac);
if (isStopRequested()) return;
// Get the response
InputStream inputStream2 = httpConn2.openInputStream();//getInputStream();
DataInputStream dataInputStream2 = new DataInputStream(inputStream2);
// Interpret the response obtained
dataInputStream2.readShort();
dataInputStream2.readByte();
if (isStopRequested()) return;
final int code = dataInputStream2.readInt();
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
Dialog.alert(code + "");
}
});
And in tryGetLocationFromDevice(), you could do this (make sure to add the member variable and new method below):
private LocationProvider _locationProvider; // must be a member variable!
public void requestStop() {
if (_locationProvider != null) {
// this will interrupt the _locationProvider.getLocation(300) call
_locationProvider.reset();
}
}
private void tryGetLocationFromDevice() {
_gotLocation = false;
try {
Criteria myCriteria = new Criteria();
myCriteria.setCostAllowed(false);
_locationProvider = LocationProvider.getInstance(myCriteria);
try {
Location myLocation = _locationProvider.getLocation(300);
setLocation(myLocation.getQualifiedCoordinates());
} catch ( InterruptedException iex ) {
// this may be caught if stop requested!!!!
System.out.println(iex.getMessage());
} catch ( LocationException lex ) {
System.out.println(lex.getMessage());
}
} catch ( LocationException lex ) {
System.out.println(lex.getMessage());
}
if (!_gotLocation && !isStopRequested()) {
getLocationFromGoogle();
}
}
Then, call the GPSThread.requestStop() method from the outer GPSHandler.requestStop() method:
public synchronized static void requestStop() {
stopRequested = true;
if (_gpsThread != null) {
_gpsThread.requestStop();
}
}