I use a pattern MVVM Caliburn Micro and in my ViewModel I have this code
private Microphone microphone;
private byte[] buffer;
private MemoryStream stream;
public MainViewModel()
{
microphone = Microphone.Default;
stream = new MemoryStream();
DispatcherTimer dt = new DispatcherTimer();
dt.Interval = TimeSpan.FromMilliseconds(50);
dt.Tick += delegate
{
try
{
FrameworkDispatcher.Update();
}
catch { }
};
dt.Start();
microphone.BufferReady += new EventHandler<EventArgs>(microphone_BufferReady);
}
void microphone_BufferReady(object sender, EventArgs e)
{
//...
}
on this
microphone.BufferReady += new EventHandler<EventArgs>(microphone_BufferReady);
receive error => System.NullReferenceException: Object reference not set to an instance of an object
Is ID_CAP_MICROPHONE capability enabled in WMAppManifest.xml? Microphone.Default returns NULL if this is not enabled.
Related
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
I'm developing an Android App and i create a slide menu. In the slide menu i have item "Search". This is a fragment that call a json (using volley) and input the result into custom list view.
Now when i call the fragment (using debug mode) the fragment start to download some data but after some record of json download the app crash and i receive this error:
E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NullPointerException
at com.firstproject.fragment.SearchFragment.loadListView(SearchFragment.java:175)
at com.firstproject.fragment.SearchFragment.access$000(SearchFragment.java:46)
at com.firstproject.fragment.SearchFragment$1.onResponse(SearchFragment.java:105)
at com.firstproject.fragment.SearchFragment$1.onResponse(SearchFragment.java:98)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:60)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:30)
at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:99)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:213)
at android.app.ActivityThread.main(ActivityThread.java:5225)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:741)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
at dalvik.system.NativeStart.main(Native Method)
I attach my code where i call a json file (for privacy delete the url json)
Any help please?
Thanks
public class SearchFragment extends Fragment {
public SearchFragment(){}
private static final String url = "http://<server_name>/<folder>/data.json";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_search, container, false);
}
ListView geoJSON;
String globalResponse="";
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
String tag_string_req = "string_req";
final ProgressDialog pDialog = new ProgressDialog(getActivity());
// Showing progress dialog before making http request
pDialog.setMessage("Loading...");
pDialog.show();
RequestQueue mRequestQueue;
Network network = new BasicNetwork(new HurlStack());
//Cache cache = new DiskBasedCache(getCacheDir(), 1024 * 1024); // 1MB cap
// Instantiate the RequestQueue with the cache and network.
Cache cache = AppController.getInstance().getRequestQueue().getCache();
mRequestQueue = new RequestQueue(cache, network);
// Start the queue
mRequestQueue.start();
Cache.Entry entry = cache.get(url);
if(entry != null){
try {
String data = new String(entry.data, "UTF-8");
//loadListView(gobalResponse,0,1000);
//Toast.makeText(getActivity(), "Cache utilized!", 0).show();
// handle data, like converting it to xml, json, bitmap etc.,
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}else{
// Cached response doesn't exists. Make network call here
StringRequest strReq = new StringRequest(Request.Method.GET,
url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
globalResponse=response;
Globals.GlobalResponse=globalResponse;
Log.d("", response.toString());
loadListView(globalResponse,0,1000);
//loadListView(response,0,1000);
pDialog.hide();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d("", "Error: " + error.getMessage());
//Toast.makeText(getApplicationContext(), error.getMessage()+"", 0).show();
pDialog.hide();
}
});
strReq.setShouldCache(true);
//strReq.
// Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}
}
private ArrayList<GeoJsonResponse> globalResponseObject;//=new ArrayList<GeoJsonResposne>();
private void loadListView(String response,float lowerLimit,float upperLimit)
{
try {
JSONObject featureCollection=new JSONObject(response);
globalResponseObject=new ArrayList<GeoJsonResponse>();
JSONArray features=featureCollection.getJSONArray("features");
for (int i = 0; i < features.length(); i++) {
JSONObject properties=features.getJSONObject(i);
float mag=Float.parseFloat(properties.getJSONObject("properties").getString("mag"));
if(!(mag>=lowerLimit&&mag<upperLimit)) continue;
Log.d("",properties.getJSONObject("properties").getString("author")
+ properties.getJSONObject("properties").getString("mag")
+ properties.getJSONObject("properties").getString("place")
+ properties.getJSONObject("geometry").getJSONArray("coordinates").getString(0)
+ properties.getJSONObject("geometry").getJSONArray("coordinates").getString(1)
+ properties.getJSONObject("geometry").getJSONArray("coordinates").getString(2)
);
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
Date date1 = format.parse(properties.getJSONObject("properties").getString("time"));
GeoJsonResponse obj=new GeoJsonResponse(
properties.getJSONObject("properties").getString("eventId"),
properties.getJSONObject("properties").getString("author"),
properties.getJSONObject("properties").getString("place"),
Double.parseDouble(properties.getJSONObject("properties").getString("mag")),
Double.parseDouble(properties.getJSONObject("geometry").getJSONArray("coordinates").getString(2)),
properties.getJSONObject("properties").getString("time"),date1,
Double.parseDouble(properties.getJSONObject("geometry").getJSONArray("coordinates").getString(0)),
Double.parseDouble(properties.getJSONObject("geometry").getJSONArray("coordinates").getString(1))
);
globalResponseObject.add(obj);}
if(lowerLimit==0)
Globals.geoJsonResponse=globalResponseObject;
// Collections.sort(globalResponseObject, new DateSorter());
CustomListAdapter adpater=new CustomListAdapter(getActivity()
, globalResponseObject);
adpater.notifyDataSetChanged();
geoJSON.setAdapter(adpater);
geoJSON.invalidate();
geoJSON.invalidateViews();
//, author, place, magnitude, distance, date)
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
This is my code for recording sound in temporary file. when i record sound and then listen to playback, everything goes well, but when i click again on playback button, i get this error:
How can i solve this problem?
Code:
using System.Collections.Generic;
using System.IO;
using System.IO.IsolatedStorage;
using System.Windows;
using System.Windows.Controls;
using Coding4Fun.Toolkit.Audio;
using Coding4Fun.Toolkit.Audio.Helpers;
namespace AudioRecorder.UserControls
{
public partial class SoundRecorderPanel : UserControl
{
private MicrophoneRecorder _recorder = new MicrophoneRecorder();
private List<IsolatedStorageFileStream> _audioList = new List<IsolatedStorageFileStream>();
private int _counter;
public SoundRecorderPanel()
{
InitializeComponent();
}
private void ButtonRecord_OnChecked(object sender, RoutedEventArgs e)
{
_recorder.Start();
}
private void ButtonRecord_OnUnchecked(object sender, RoutedEventArgs e)
{
_recorder.Stop();
SaveTempAudio(_recorder.Buffer);
}
private void SaveTempAudio(MemoryStream buffer)
{
if (_counter==2)
return;
using (IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication())
{
var bytes = buffer.GetWavAsByteArray(_recorder.SampleRate);
var tempFileName = "tempwaveFile_"+_counter;
IsolatedStorageFileStream audioStream = isoStore.CreateFile(tempFileName);
audioStream.Write(bytes,0,bytes.Length);
_audioList.Add(audioStream);
_counter++;
}
}
private void ButtonPlayBack_OnClick(object sender, RoutedEventArgs e)
{
var index = int.Parse(((Button) sender).Tag.ToString());
var audioPlayer = new MediaElement {AutoPlay = true};
if (index < _audioList.Count)
{
audioPlayer.SetSource(_audioList[index]);
LayoutRoot.Children.Add(audioPlayer);
audioPlayer.Play();
}
}
}
}
You can 100% use a using block. Issue was how you were attempting to access the stream in the separate event. Reopen it rather than attempt to save a reference in an index to the stream.
using (var stream = new IsolatedStorageFileStream(_fileName, FileMode.Open, storageFolder))
{
playBack.SetSource(stream);
playBack.Play();
}
Use the sample code:
https://coding4fun.codeplex.com/SourceControl/latest#source/Coding4Fun.Toolkit.Test.WindowsPhone.Common/Samples/Audio.xaml.cs
I solved my problem , it's weird but it seems using(){} does not work ! and i disposed IsolatedStorageFile and IsolatedStorageFileStream manually . and also i changed the code under ButtonPlayBack click event . this is my new code for someone who has a same problem .
private void SaveTempAudio(MemoryStream buffer)
{
if (_counter == 2)
return;
var isoStore = IsolatedStorageFile.GetUserStoreForApplication();
var bytes = buffer.GetWavAsByteArray(_recorder.SampleRate);
var tempFileName = "tempwave_" + _counter;
var audioStream = isoStore.CreateFile(tempFileName);
audioStream.Write(bytes, 0, bytes.Length);
_audioList.Add(audioStream);
_counter++;
isoStore.Dispose();
audioStream.Close();
audioStream.Dispose();
}
private void ButtonPlayBack_OnClick(object sender, RoutedEventArgs e)
{
var index = int.Parse(((Button) sender).Tag.ToString());
var fileName = "tempwave_" + ((Button) sender).Tag;
if (index >= _audioList.Count)
return;
var isoStorage = IsolatedStorageFile.GetUserStoreForApplication();
var fileStream = isoStorage.OpenFile(fileName, FileMode.Open, FileAccess.Read);
SoundPlayer.SetSource(fileStream);
SoundPlayer.Play();
isoStorage.Dispose();
fileStream.Close();
fileStream.Dispose();
}
I would like to run a task during the waiting of a web request. If the task finishes before the request can return a response, then I would display a message "The server is taking too long". I'm using a WebClient object, how can I manage the time out?
public Class Result
{
protected override void OnNavigatedTo(NavigationEventArgs e)
{
if (NavigationContext.QueryString.TryGetValue("critere", out sCritere))
{
try
{
_datamanager = new DataManager();
_datamanager.m_evt_Client_DownloadStringCompleted += OnDownloadStringCompleted;
_datamanager.DownloadXmlData(DataManager.URL_RECHERCHE, sCritere);
//HERE I NEED TO RUN A TIMER If the response is too long i would display a message
}
catch(Exception ex)
{
MessageBox.Show(ex.Message, "Erreur", MessageBoxButton.OK);
NavigationService.GoBack();
NavigationService.RemoveBackEntry();
}
}
}
}
public Class DataManager
{
public void DownloadXmlData(string uri, string critere = "")
{
try
{
WebClient client = new WebClient();
client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(client_DownloadStringCompleted);
client.Credentials = new NetworkCredential(UserSaved, PasswordSaved, domain);
client.DownloadStringAsync(new Uri(uri + critere));
}
catch(WebException )
{
throw new WebException(MyExceptionsMessages.Webexception) ;
}
catch (Exception )
{
throw new UnknowException(MyExceptionsMessages.UnknownError);
}
}
public void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
//raise Downloadstringcompleted event if error==null
}
}
You can use BackgroundWorker..
BackgroundWorker bw = new BackgroundWorker();
bw.DoWork += (s, e) =>
{
// your task to do while webclient is downloading
};
bw.RunWorkerCompleted += (s, e) =>
{
// check whether DownloadStringCompleted is fired or not
// if not, cancel the WebClient's asynchronous call and show your message.
client.CancelAsync();
MessageBox.Show("message");
}
client.DownloadStringAsync(uri);
bw.RunWorkerAsync();
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);
}
}