Accurate Windows phone 8.1 geolocation? - windows-phone-8

Im working with windows phone 8.1 geolocation. The problem that I currently have is that my code only shows the first numbers of my coordinate. Example: If the coordinate is "41.233" the app only shows "41.00" . I need it to be as accurate as possible. In case it matters, im using windows phone 8.1 emulator to try the app, not an actual phone.
My code:
public sealed partial class MainPage : Page
{
bool shouldSend = false;
DispatcherTimer timer = new DispatcherTimer();
public MainPage()
{
this.InitializeComponent();
this.NavigationCacheMode = NavigationCacheMode.Required;
}
private async Task GetLocation()
{
Geolocator geolocator = new Geolocator();
geolocator.DesiredAccuracy = Windows.Devices.Geolocation.PositionAccuracy.High;
try
{
Geoposition geoposition = await geolocator.GetGeopositionAsync(
maximumAge: TimeSpan.FromSeconds(1),
timeout: TimeSpan.FromSeconds(10)
);
LatitudeTxt.Text = geoposition.Coordinate.Latitude.ToString("0.00");
LongitudeTxt.Text = geoposition.Coordinate.Longitude.ToString("0.00");
LatLonTxt.Text = LatitudeTxt.Text + ", " + LongitudeTxt.Text;
var speed = geoposition.Coordinate.Speed.ToString();
ProcessingTxt.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
string result = "";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(
"http://proyecto-busways.rhcloud.com/colectivos?p=lta123&l=80&d=moyano&lat=" + LatitudeTxt.Text + "&lon=" + LongitudeTxt.Text + "&v=" + speed + "&Accion=Agregar");
request.ContinueTimeout = 4000;
request.Credentials = CredentialCache.DefaultNetworkCredentials;
using (HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync())
{
if (response.StatusCode == HttpStatusCode.OK)
{
//To obtain response body
using (Stream streamResponse = response.GetResponseStream())
{
using (StreamReader streamRead = new StreamReader(streamResponse, Encoding.UTF8))
{
result = streamRead.ReadToEnd();
}
}
}
}
}
catch (Exception ex)
{
ProcessingTxt.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
if ((uint)ex.HResult == 0x80004004)
{
// the application does not have the right capability or the location master switch is off
}
//else
{
// something else happened acquring the location
}
}
}
/// <summary>
/// Invoked when this page is about to be displayed in a Frame.
/// </summary>
/// <param name="e">Event data that describes how this page was reached.
/// This parameter is typically used to configure the page.</param>
protected override void OnNavigatedTo(NavigationEventArgs e)
{
// TODO: Prepare page for display here.
// TODO: If your application contains multiple pages, ensure that you are
// handling the hardware Back button by registering for the
// Windows.Phone.UI.Input.HardwareButtons.BackPressed event.
// If you are using the NavigationHelper provided by some templates,
// this event is handled for you.
}
private async void StartSending_Click(object sender, RoutedEventArgs e)
{
await GetLocation();
timer.Tick += timer_Tick;
timer.Interval = new TimeSpan(0, 0, 5);
timer.Start();
StartSending.IsEnabled = false;
}
async void timer_Tick(object sender, object e)
{
ProcessingTxt.Visibility = Windows.UI.Xaml.Visibility.Visible;
await GetLocation();
}
private void EndSending_Click(object sender, RoutedEventArgs e)
{
timer.Tick -= timer_Tick;
timer.Stop();
StartSending.IsEnabled = true;
EndSending.IsEnabled = false;
}
private void GPS_Tapped(object sender, TappedRoutedEventArgs e)
{
Frame.Navigate(typeof(ContactPage));
}
}
Thanks for your help!

Did you try out the Geolocator.DesiredAccuracyInMeters property?
geolocator.DesiredAccuracyInMeters = 3;
Reference & Sample

In this point LatitudeTxt.Text = geoposition.Coordinate.Latitude.ToString("0.00");
LongitudeTxt.Text = geoposition.Coordinate.Longitude.ToString("0.00");
You indicated that you have 0.00 decimals, for more accuracy you should put 0.000000

Related

How cancel Async Call in Windows Phone?

I have a list wich is loaded with elements each time the user make a research...These elements contain an Icon which is dowloaded with an async method GetByteArrayAsync of the HttpClient object. I have an issue when the user make a second research while the icon of the first list are still downloading.Because the list of elements is changing while Icon downloads are processing on each element of the first list. So my guess is that I need to cancel these requests each time the user proceed to a new research...Ive readen some stuuf on Task.run and CancellationTokenSource but I can't find really helpful example for my case so here is my code...Hope you can help me with that ...Thank you
public static async Task<byte[]> DownloadElementFile(BdeskElement bdeskElement)
{
//create and send the request
DataRequest requesteur = new DataRequest();
byte[] encryptedByte = await requesteur.GetBytesAsync(dataRequestParam);
return encryptedByte;
}
public async Task<Byte[]> GetBytesAsync(DataRequestParam datarequesparam)
{
var handler = new HttpClientHandler { Credentials = new NetworkCredential(datarequesparam.AuthentificationLogin, datarequesparam.AuthentificationPassword, "bt0d0000") };
HttpClient httpClient = new HttpClient(handler);
try
{
byte[] BytesReceived = await httpClient.GetByteArrayAsync(datarequesparam.TargetUri);
if (BytesReceived.Length > 0)
{
return BytesReceived;
}
else
{
return null;
}
}
catch (WebException)
{
throw new MyException(MyExceptionsMessages.Webexception);
}
}
EDIT
public async Task<Byte[]> GetBytesAsync(DataRequestParam datarequesparam)
{
var handler = new HttpClientHandler { Credentials = new NetworkCredential(datarequesparam.AuthentificationLogin, datarequesparam.AuthentificationPassword, "bt0d0000") };
HttpClient httpClient = new HttpClient(handler);
try
{
cts = new CancellationTokenSource();
HttpResponseMessage reponse = await httpClient.GetAsync(datarequesparam.TargetUri,cts.Token);
if (reponse.StatusCode == HttpStatusCode.OK)
{
byte[] BytesReceived = reponse.Content.ReadAsByteArrayAsync().Result;
if (BytesReceived.Length > 0)
{
return BytesReceived;
}
else
{
return null;
}
}
else
{
return null;
}
}
catch (WebException)
{
throw new MyException(MyExceptionsMessages.Webexception);
}
catch(OperationCanceledException)
{
throw new OperationCanceledException();
}
EDIT2
I need to cancel this funntion when the user make a new research and the list "listBoxGetDocsLibs" changed.
private async void LoadIconDocLibs()
{
foreach (var doclib in listBoxGetDocsLibs)//ERROR HERE COLLECTION HAS CHANGED
{
doclib.Icon = new BitmapImage();
try
{
byte[] Icon = await ServerFunctions.GetDocLibsIcon(doclib);
if (Icon != null)
{
{
var ms = new MemoryStream(Icon);
BitmapImage photo = new BitmapImage();
photo.DecodePixelHeight = 64;
photo.DecodePixelWidth = 92;
photo.SetSource(ms);
doclib.Icon = photo;
}
}
}
catch(OperationCanceledException)
{
}
}
}
First you need to define CancellationTokenSource:
private System.Threading.CancellationTokenSource cts;
place above code somewhere, where you can access it with your Button or other method.
Unfortunately GetByteArrayAsync lacks Cancelling - so it cannot be used with cts.Token, but maybe you can accomplish your task using GetAsync - which supports Cancelling:
ctsDownload = new System.Threading.CancellationTokenSource();
HttpResponseMessage response = await httpClient.GetAsync(requestUri, cts.Token);
Then you can get your content from response.
And when you want to Cancel your Task it can look like this:
private void cancelBtn_Click(object sender, RoutedEventArgs e)
{
if (this.cts != null)
this.cts.Cancel();
}
When you Cancel task an Exception will be thrown.
If you want to cancel your own async Task, a good example you can find at Stephen Cleary blog.
EDIT - you can also build your own method (for example with HttpWebRequest) which will support Cancelling:
For this purpose you will have to extend HttpWebRequest (under WP it lacks GetResponseAsync):
// create a static class in your namespace
public static class Extensions
{
public static Task<HttpWebResponse> GetResponseAsync(this HttpWebRequest webRequest)
{
TaskCompletionSource<HttpWebResponse> taskComplete = new TaskCompletionSource<HttpWebResponse>();
webRequest.BeginGetResponse(
asyncResponse =>
{
try
{
HttpWebRequest responseRequest = (HttpWebRequest)asyncResponse.AsyncState;
HttpWebResponse someResponse = (HttpWebResponse)responseRequest.EndGetResponse(asyncResponse);
taskComplete.TrySetResult(someResponse);
}
catch (WebException webExc)
{
HttpWebResponse failedResponse = (HttpWebResponse)webExc.Response;
taskComplete.TrySetResult(failedResponse);
}
catch (Exception exc) { taskComplete.SetException(exc); }
}, webRequest);
return taskComplete.Task;
}
}
Then your method can look like this:
public async Task<Byte[]> GetBytesAsync(DataRequestParam datarequesparam, CancellationToken ct)
{
HttpWebRequest request = HttpWebRequest.CreateHttp(datarequesparam.TargetUri);
request.Method = "GET";
request.Credentials = new NetworkCredential(datarequesparam.AuthentificationLogin, datarequesparam.AuthentificationPassword, "bt0d0000");
request.AllowReadStreamBuffering = false;
try
{
if (request != null)
{
using (HttpWebResponse response = await request.GetResponseAsync())
using (Stream mystr = response.GetResponseStream())
using (MemoryStream output = new MemoryStream())
{
const int BUFFER_SIZE = 10 * 1024;
byte[] buf = new byte[BUFFER_SIZE];
int bytesread = 0;
while ((bytesread = await mystr.ReadAsync(buf, 0, BUFFER_SIZE)) > 0)
{
output.Write(buf, 0, bytesread);
ct.ThrowIfCancellationRequested();
}
return output.ToArray();
}
}
else return null;
}
catch (WebException)
{
throw new MyException(MyExceptionsMessages.Webexception);
}
}
You can freely change Buffer Size which will affect how often Cancellation will be checked.
I haven't tried this but I think it should work.

Waiting and Return a result with DownloadStringAsync WP8

I do a webrequest with DownloadStringAsync() but I need to return the result only when the DownloadStringCompleted event has been called. After the downloadasync-method, I need to wait for the result and then I could return it in a string property. So I implemented a while(Result == "") but I don't know what to do there. I already tried Thread.sleep(500) but it seems the download never gets completed. And the code remains in the while forever.
string Result = "";
public String Query(DataRequestParam dataRequestParam)
{
try
{
WebClient web = new WebClient();
if (!string.IsNullOrEmpty(dataRequestParam.AuthentificationLogin))
{
System.Net.NetworkCredential account = new NetworkCredential(dataRequestParam.AuthentificationLogin, dataRequestParam.AuthentificationPassword);
web.Credentials = account;
}
web.DownloadStringCompleted += OnDownloadStringCompleted;
web.DownloadStringAsync(dataRequestParam.TargetUri);
while (Result == "")
{
//What am i supposed to do here ?
}
return Result;
}
catch(WebException we)
{
MessageBox.Show(we.Message);
return null;
}
}
private void OnDownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
if (e.Error != null)
{
//Error treating
}
else
{
Result = e.Result;
}
}
UI CODE
protected override void OnNavigatedTo(NavigationEventArgs e)
{
base.OnNavigatedTo(e);
if (e.NavigationMode != NavigationMode.Back)
{
ServerFunctions.SetUserProfil(User.UserLogin,User.UserPassword);
this.listBoxGetDocsLibs.Clear();
List<BdeskDocLib> list = new List<BdeskDocLib>();
try
{
//HERE THE START OF THE DOWNLOAD
ServerFunctions.GetDocLibs(true);
}
catch (Exception ex)
{
//error
}
foreach (BdeskDocLib docLib in list)
{
this.listBoxGetDocsLibs.Add(docLib);
}
}
}
the ServerFunction static class
public static List<BdeskDocLib> GetDocLibs(bool onlyDocLibPerso)
{
string xmlContent = GetXml(URL_GETDOCLIBS);
List<BdeskDocLib> result = BdeskDocLib.GetListFromXml(xmlContent, onlyDocLibPerso);
return result;
}
private static String GetXml(string partialUrl)
{
string url = GenerateUrl(partialUrl);
DataRequestParam dataRequestParam = new DataRequestParam();
dataRequestParam.TargetUri = new Uri(url);
dataRequestParam.UserAgent = "BSynchro";
dataRequestParam.AuthentificationLogin = userLogin;
dataRequestParam.AuthentificationPassword = userPwd;
//HERE I START THE QUERY method
// NEED QUERY RETURNS A STRING or Task<String>
DataRequest requesteur = new DataRequest();
xmlResult=requesteur.Query(dataRequestParam);
if (CheckErrorConnexion(xmlResult) == false)
{
throw new Exception("Erreur du login ou mot de passe");
}
return xmlResult;
}
There is nothing good in blocking main UI (unless you really need to). But if you want to wait for your result you can make some use of async-await and TaskCompletitionSource - you can find more about on this blog and how to use TCS in this answer:
public static Task<string> myDownloadString(DataRequestParam dataRequestParam)
{
var tcs = new TaskCompletionSource<string>();
var web = new WebClient();
if (!string.IsNullOrEmpty(dataRequestParam.AuthentificationLogin))
{
System.Net.NetworkCredential account = new NetworkCredential(dataRequestParam.AuthentificationLogin, dataRequestParam.AuthentificationPassword);
web.Credentials = account;
}
web.DownloadStringCompleted += (s, e) =>
{
if (e.Error != null) tcs.TrySetException(e.Error);
else if (e.Cancelled) tcs.TrySetCanceled();
else tcs.TrySetResult(e.Result);
};
web.DownloadStringAsync(dataRequestParam.TargetUri);
return tcs.Task;
}
public async Task<string> Query(DataRequestParam dataRequestParam)
{
string Result = "";
try
{
Result = await myDownloadString(dataRequestParam);
}
catch (WebException we)
{
MessageBox.Show(we.Message);
return null;
}
return Result;
}
(I've not tried this code, there maight be some mistakes, but it should work)
Basing on this code you can also extend your WebClient with awaitable version of download string.

I am getting error in LoginAsync method during wp8 App development for sky drive

I am developing a windows phone 8 application to access sky drive. I am getting following error when I call LoginAsync() method-
An exception of type 'Microsoft.Live.LiveAuthException' occurred in mscorlib.ni.dll but was not handled in user code
using System;
using System.Windows;
using Microsoft.Phone.Controls;
using Microsoft.Live;
namespace SkyDriveApp
{
public partial class MainPage : PhoneApplicationPage
{
// Constructor
LiveConnectClient client;
public MainPage()
{
InitializeComponent();
}
public async void Auth()
{
string clientId = "My_client_id";
LiveAuthClient auth = new LiveAuthClient(clientId);
// var result = await auth.InitializeAsync(new[] { "wl.basic", "wl.signin", "wl.skydrive_update" });
var result = await auth.LoginAsync(new[] { "wl.basic", "wl.signin", "wl.skydrive_update" });
if (result.Status == LiveConnectSessionStatus.Connected)
{
client = new LiveConnectClient(result.Session);
tbMessage.Text = "Connected!";
}
}
private void btnLogin_SessionChanged(object sender, Microsoft.Live.Controls.LiveConnectSessionChangedEventArgs e)
{
Auth();
}
}
}
I see that you are using provided login buton, try this:
In xaml:
<live:SignInButton Name="skyBtn" ClientId="your client ID" Scopes="wl.signin wl.skydrive wl.skydrive_update" Branding="Skydrive" TextType="Login"/>
In code behind:
private void skyBtn_SessionChanged(object sender, Microsoft.Live.Controls.LiveConnectSessionChangedEventArgs e)
{
if (e.Status == LiveConnectSessionStatus.Connected)
{
session = e.Session;
client = new LiveConnectClient(session);
tbMessage.Text = "Connected!";
}
else tbMessage.Text = "Not Connected!";
if (e.Error != null)
{
tbMessage.Text = "Not Connected!";
Dispatcher.BeginInvoke(() =>
{
MessageBox.Show(e.Error.Message);
});
}
}

WebClient event firing order

I'm new to WP7 app development and I'm having trouble passing parameters to an API on a website.
It's my understanding that the onNavigatedTo() is fired first when a page is open on the WP7, however when I try to grab the parameters the webClient_DownloadStringCompleted() is fired first.
public partial class Ranks : PhoneApplicationPage
{
private WebClient webClient;
private string pageType;
private string pagePosition;
public Ranks()
{
InitializeComponent();
this.webClient = new WebClient();
string header_auth = "application/json";
this.webClient.DownloadStringCompleted += new DownloadStringCompletedEventHandler(webClient_DownloadStringCompleted);
this.webClient.Headers[HttpRequestHeader.Authorization] = header_auth;
Uri serviceUri = new Uri(#"http://www.example.com/api/API.php?type=" + pageType + "&position=" + pagePosition);
this.webClient.DownloadStringAsync(serviceUri);
}
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
string type, position;
if (NavigationContext.QueryString.TryGetValue("type", out type))
{
pageType = type;
}
if (NavigationContext.QueryString.TryGetValue("pos", out position))
{
pagePosition = position;
}
}
void webClient_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
string myJsonString = e.Result;
List<PlayerDetails> dataSource = new List<PlayerDetails>();
//load into memory stream
using (var ms = new MemoryStream(Encoding.Unicode.GetBytes(myJsonString)))
{
//parse into jsonser
var ser = new DataContractJsonSerializer(typeof(PlayerDetails[]));
PlayerDetails[] obj = (PlayerDetails[])ser.ReadObject(ms);
foreach (PlayerDetails plyr in obj)
{
dataSource.Add(plyr);
}
playerList.ItemsSource = dataSource;
}
}
Whenever the URI string is built it's missing the parameters 'pageType' and 'pagePosition'
Any help would be greatly appreciated!
The class constructor will always get called before OnNavigatedTo. you should move that code from the constructor, and into OnNavigatedTo (or Loaded).
I'm guessing that you have that code in the constructor because you only want it to happen once per page load (i.e. not when the user navigates Back onto the page). If that's the case, you can check the NavigationMode.
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
if (e.NavigationMode == NavigationMode.New)
{
string type, position;
if (NavigationContext.QueryString.TryGetValue("type", out type))
{
pageType = type;
}
if (NavigationContext.QueryString.TryGetValue("pos", out position))
{
pagePosition = position;
}
this.webClient = new WebClient();
string header_auth = "application/json";
this.webClient.DownloadStringCompleted += new DownloadStringCompletedEventHandler(webClient_DownloadStringCompleted);
this.webClient.Headers[HttpRequestHeader.Authorization] = header_auth;
Uri serviceUri = new Uri(#"http://www.example.com/api/API.php?type=" + pageType + "&position=" + pagePosition);
this.webClient.DownloadStringAsync(serviceUri);
}
}

Http Post with Blackberry 6.0 issue

I am trying to post some data to our webservice(written in c#) and get the response. The response is in JSON format.
I am using the Blackberry Code Sample which is BlockingSenderDestination Sample. When I request a page it returns with no problem. But when I send my data to our webservice it does not return anything.
The code part that I added is :
ByteMessage myMsg = bsd.createByteMessage();
//myMsg.setStringPayload("I love my BlackBerry device!");
myMsg.setMessageProperty("querytpe","myspecialkey");//here is my post data
myMsg.setMessageProperty("uname","myusername");
myMsg.setMessageProperty("pass","password");
((HttpMessage) myMsg).setMethod(HttpMessage.POST);
// Send message and wait for response myMsg
response = bsd.sendReceive(myMsg);
What am i doing wrong? And what is the alternatives or more efficients way to do Post with Blackberry.
Regards.
Here is my whole code:
class BlockingSenderSample extends MainScreen implements FieldChangeListener {
ButtonField _btnBlock = new ButtonField(Field.FIELD_HCENTER);
private static UiApplication _app = UiApplication.getUiApplication();
private String _result;
public BlockingSenderSample()
{
_btnBlock.setChangeListener(this);
_btnBlock.setLabel("Fetch page");
add(_btnBlock);
}
public void fieldChanged(Field button, int unused)
{
if(button == _btnBlock)
{
Thread t = new Thread(new Runnable()
{
public void run()
{
Message response = null;
String uriStr = "http://192.168.1.250/mobileServiceOrjinal.aspx"; //our webservice address
//String uriStr = "http://www.blackberry.com";
BlockingSenderDestination bsd = null;
try
{
bsd = (BlockingSenderDestination)
DestinationFactory.getSenderDestination
("name", URI.create(uriStr));//name for context is name. is it true?
if(bsd == null)
{
bsd =
DestinationFactory.createBlockingSenderDestination
(new Context("ender"),
URI.create(uriStr)
);
}
//Dialog.inform( "1" );
ByteMessage myMsg = bsd.createByteMessage();
//myMsg.setStringPayload("I love my BlackBerry device!");
myMsg.setMessageProperty("querytpe","myspecialkey");//here is my post data
myMsg.setMessageProperty("uname","myusername");
myMsg.setMessageProperty("pass","password");
((HttpMessage) myMsg).setMethod(HttpMessage.POST);
// Send message and wait for response myMsg
response = bsd.sendReceive(myMsg);
if(response != null)
{
BSDResponse(response);
}
}
catch(Exception e)
{
//Dialog.inform( "ex" );
// process the error
}
finally
{
if(bsd != null)
{
bsd.release();
}
}
}
});
t.start();
}
}
private void BSDResponse(Message msg)
{
if (msg instanceof ByteMessage)
{
ByteMessage reply = (ByteMessage) msg;
_result = (String) reply.getStringPayload();
} else if(msg instanceof StreamMessage)
{
StreamMessage reply = (StreamMessage) msg;
InputStream is = reply.getStreamPayload();
byte[] data = null;
try {
data = net.rim.device.api.io.IOUtilities.streamToBytes(is);
} catch (IOException e) {
// process the error
}
if(data != null)
{
_result = new String(data);
}
}
_app.invokeLater(new Runnable() {
public void run() {
_app.pushScreen(new HTTPOutputScreen(_result));
}
});
}
}
..
class HTTPOutputScreen extends MainScreen
{
RichTextField _rtfOutput = new RichTextField();
public HTTPOutputScreen(String message)
{
_rtfOutput.setText("Retrieving data. Please wait...");
add(_rtfOutput);
showContents(message);
}
// After the data has been retrieved, display it
public void showContents(final String result)
{
UiApplication.getUiApplication().invokeLater(new Runnable()
{
public void run()
{
_rtfOutput.setText(result);
}
});
}
}
HttpMessage does not extend ByteMessage so when you do:
((HttpMessage) myMsg).setMethod(HttpMessage.POST);
it throws a ClassCastException. Here's a rough outline of what I would do instead. Note that this is just example code, I'm ignoring exceptions and such.
//Note: the URL will need to be appended with appropriate connection settings
HttpConnection httpConn = (HttpConnection) Connector.open(url);
httpConn.setRequestMethod(HttpConnection.POST);
OutputStream out = httpConn.openOutputStream();
out.write(<YOUR DATA HERE>);
out.flush();
out.close();
InputStream in = httpConn.openInputStream();
//Read in the input stream if you want to get the response from the server
if(httpConn.getResponseCode() != HttpConnection.OK)
{
//Do error handling here.
}