Xamarin.Forms Webview OnDetachedFromWindow crashed - xamarin

When open renderer page many times, when back to last page, it crashed and log this exception:
System.NotSupportedException: Unable to activate instance of type
AppZPMC.Droid.Renderers.CustomVideoWebViewRenderer from native handle
0xff9919cc (key_handle 0xf2ff0de).
Here is my code:
public class CustomVideoWebViewRenderer : WebViewRenderer
{
string url;
Activity activity;
WebView webView;
View customView;
CustomVideoWebView element;
FrameLayout.LayoutParams COVER_SCREEN_PARAMS = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MatchParent, ViewGroup.LayoutParams.MatchParent);
FrameLayout fullscreenContainer;
WebChromeClient.ICustomViewCallback customViewCallback;
public CustomVideoWebViewRenderer(Context context) : base(context)
{
}
protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.WebView> e)
{
base.OnElementChanged(e);
webView = this.Control;
activity = CrossCurrentActivity.Current.Activity;
if (e.NewElement != null)
{
element = e.NewElement as CustomVideoWebView;
url = element.VideoUrl;
}
if (webView != null)
{
InitWebView();
}
}
protected override void OnDetachedFromWindow()
{
if (Element == null)
{
return;
}
base.OnDetachedFromWindow();
if (Control != null)
{
Control.StopLoading();
Control.LoadUrl("");
Control.Reload();
Control.Destroy();
}
}
public void FullScreen(Activity pActivity)
{
element.IsFullScreen = true;
WindowManagerLayoutParams attrs = pActivity.Window.Attributes;
attrs.Flags |= WindowManagerFlags.Fullscreen;
attrs.Flags |= WindowManagerFlags.KeepScreenOn;
pActivity.Window.Attributes = attrs;
pActivity.RequestedOrientation = Android.Content.PM.ScreenOrientation.Landscape;
}
public void SmallScreen(Activity pActivity)
{
element.IsFullScreen = false;
WindowManagerLayoutParams attrs = pActivity.Window.Attributes;
attrs.Flags &= ~WindowManagerFlags.Fullscreen;
attrs.Flags &= ~WindowManagerFlags.KeepScreenOn;
pActivity.Window.Attributes = attrs;
pActivity.RequestedOrientation = Android.Content.PM.ScreenOrientation.UserPortrait;
}
private void InitWebView()
{
WebChromeClient wvcc = new WebChromeClient();
WebSettings webSettings = webView.Settings;
webSettings.JavaScriptEnabled = true;
webSettings.SetSupportZoom(false);
webSettings.CacheMode = CacheModes.NoCache;
webView.SetWebViewClient(new VideoWebViewClient());
FrameLayout frameLayout = new FrameLayout(activity.ApplicationContext);
frameLayout.LayoutParameters = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MatchParent, ViewGroup.LayoutParams.MatchParent);
webView.SetWebChromeClient(new VideoWebChromeClient(frameLayout, ShowCustomView, HideCustomView));
webView.LoadUrl(url);
}
private class VideoWebViewClient : WebViewClient
{
public override bool ShouldOverrideUrlLoading(WebView view, IWebResourceRequest request)
{
view.LoadUrl(request.Url.ToString());
return base.ShouldOverrideUrlLoading(view, request);
}
}
private class VideoWebChromeClient : WebChromeClient
{
FrameLayout frameLayout;
Action HideCustomView;
Action<View, ICustomViewCallback> ShowCustomView;
public VideoWebChromeClient(FrameLayout frameLayout, Action<View, ICustomViewCallback> showCustomView, Action hideCustomView)
{
this.frameLayout = frameLayout;
ShowCustomView = showCustomView;
HideCustomView = hideCustomView;
}
public override View VideoLoadingProgressView => frameLayout;
public override void OnShowCustomView(View view, ICustomViewCallback callback)
{
ShowCustomView(view, callback);
base.OnShowCustomView(view, callback);
}
public override void OnHideCustomView()
{
HideCustomView();
base.OnHideCustomView();
}
}
private void ShowCustomView(View view, WebChromeClient.ICustomViewCallback callback)
{
if (customView != null)
{
callback.OnCustomViewHidden();
return;
}
FrameLayout decor = (FrameLayout)activity.Window.DecorView;
fullscreenContainer = new FullscreenHolder(activity.ApplicationContext);
fullscreenContainer.AddView(view, COVER_SCREEN_PARAMS);
decor.AddView(fullscreenContainer, COVER_SCREEN_PARAMS);
customView = view;
customViewCallback = callback;
FullScreen(activity);
}
private void HideCustomView()
{
if (customView == null)
{
return;
}
FrameLayout decor = (FrameLayout)activity.Window.DecorView;
decor.RemoveView(fullscreenContainer);
fullscreenContainer = null;
customView = null;
customViewCallback.OnCustomViewHidden();
webView.Visibility = ViewStates.Visible;
SmallScreen(activity);
}
private class FullscreenHolder : FrameLayout
{
public FullscreenHolder(Context ctx) : base(ctx)
{
SetBackgroundColor(Color.Black);
}
public override bool OnTouchEvent(MotionEvent e)
{
return true;
}
}
}
This is full crash log:
Java.Lang.Error: Exception of type 'Java.Lang.Error' was thrown.
java.lang.Error: Java callstack:
md5ff1c77b81adfd2c553f48967fc623ae5.CustomVideoWebViewRenderer.n_onDetachedFromWindow(Native Method)
md5ff1c77b81adfd2c553f48967fc623ae5.CustomVideoWebViewRenderer.onDetachedFromWindow(CustomVideoWebViewRenderer.java:45)
android.view.View.dispatchDetachedFromWindow(View.java:14595)
android.view.ViewGroup.dispatchDetachedFromWindow(ViewGroup.java:3074)
android.view.ViewGroup.removeAllViewsInLayout(ViewGroup.java:4792)
android.view.ViewGroup.removeAllViews(ViewGroup.java:4738)
md5270abb39e60627f0f200893b490a1ade.FragmentContainer.n_onDestroyView(Native Method)
md5270abb39e60627f0f200893b490a1ade.FragmentContainer.onDestroyView(FragmentContainer.java:59)
android.support.v4.app.Fragment.performDestroyView(Fragment.java:2480)
android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1422)
android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1569)
android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:753)
android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2415)
android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2201)
android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2155)
android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2064)
android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:718)
android.os.Handler.handleCallback(Handler.java:742)
android.os.Handler.dispatchMessage(Handler.java:95)
android.os.Looper.loop(Looper.java:157)
android.app.ActivityThread.main(ActivityThread.java:5551)
java.lang.reflect.Method.invoke(Native Method)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:742)
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:632)

Its common problem (bug) in Xamarin.Forms, take a look at: https://github.com/xamarin/Xamarin.Forms/issues/1646, no fix yet :(

Related

Remove Placeholder from TextInputLayout in Xamarin Forms for Android & IOS

I am trying to create Suggestion Searchbar using Entry
i was able to create the suggestion searchbar but i am not able to change the look of this Entry, i want to remove the tooltip above (Search by Speciality..) and just want it to look like other entry in the app
could anyone help me what and where i had to make change for getting that look
here is my code
Xamarin Android :
[assembly: ExportRenderer(typeof(AutoCompleteViewv2),
typeof(AutoCompleteViewRendererv2))]
namespace App.Droid.Renderers.RevisedRenderer
{
public class AutoCompleteViewRendererv2 :
FormsAppCompat.ViewRenderer<AutoCompleteViewv2, TextInputLayout>
{
public AutoCompleteViewRendererv2(Context context) : base(context)
{
}
private AppCompatAutoCompleteTextView NativeControl => Control?.EditText
as AppCompatAutoCompleteTextView;
protected override TextInputLayout CreateNativeControl()
{
var textInputLayout = new TextInputLayout(Context);
var autoComplete = new AppCompatAutoCompleteTextView(Context)
{
BackgroundTintList = ColorStateList.ValueOf(GetPlaceholderColor()),
Text = Element?.Text,
Hint = Element?.Placeholder,
};
GradientDrawable gd = new GradientDrawable();
gd.SetColor(global::Android.Graphics.Color.Transparent);
autoComplete.SetBackground(gd);
if (Element != null)
{
autoComplete.SetHintTextColor(Element.PlaceholderColor.ToAndroid());
autoComplete.SetTextColor(Element.TextColor.ToAndroid());
}
textInputLayout.AddView(autoComplete);
return textInputLayout;
}
protected override void OnElementChanged(ElementChangedEventArgs<AutoCompleteViewv2> e)
{
base.OnElementChanged(e);
if (e.OldElement != null)
{
// unsubscribe
NativeControl.ItemClick -= AutoCompleteOnItemSelected;
var elm = e.OldElement;
elm.CollectionChanged -= ItemsSourceCollectionChanged;
}
if (e.NewElement != null)
{
SetNativeControl(CreateNativeControl());
// subscribe
SetItemsSource();
SetThreshold();
KillPassword();
NativeControl.TextChanged += (s, args) => Element.RaiseTextChanged(NativeControl.Text);
NativeControl.ItemClick += AutoCompleteOnItemSelected;
var elm = e.NewElement;
elm.CollectionChanged += ItemsSourceCollectionChanged;
}
}
protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
base.OnElementPropertyChanged(sender, e);
if (e.PropertyName == Entry.IsPasswordProperty.PropertyName)
KillPassword();
if (e.PropertyName == AutoCompleteViewv2.ItemsSourceProperty.PropertyName)
SetItemsSource();
else if (e.PropertyName == AutoCompleteViewv2.ThresholdProperty.PropertyName)
SetThreshold();
}
private void AutoCompleteOnItemSelected(object sender, AdapterView.ItemClickEventArgs args)
{
var view = (AutoCompleteTextView)sender;
var selectedItemArgs = new SelectedItemChangedEventArgs(view.Text);
var element = (AutoCompleteViewv2)Element;
element.OnItemSelectedInternal(Element, selectedItemArgs);
}
private void ItemsSourceCollectionChanged(object sender, NotifyCollectionChangedEventArgs notifyCollectionChangedEventArgs)
{
var element = (AutoCompleteViewv2)Element;
ResetAdapter(element);
}
private void KillPassword()
{
if (Element.IsPassword)
throw new NotImplementedException("Cannot set IsPassword on a AutoComplete");
}
private void ResetAdapter(AutoCompleteViewv2 element)
{
var adapter = new BoxArrayAdapter(Context,
Android.Resource.Layout.SimpleDropDownItem1Line,
element.ItemsSource.ToList(),
element.SortingAlgorithm);
NativeControl.Adapter = adapter;
adapter.NotifyDataSetChanged();
}
private void SetItemsSource()
{
var element = (AutoCompleteViewv2)Element;
if (element.ItemsSource == null) return;
ResetAdapter(element);
}
private void SetThreshold()
{
var element = (AutoCompleteViewv2)Element;
NativeControl.Threshold = element.Threshold;
}
#region Section 2
protected AColor GetPlaceholderColor() => Element.PlaceholderColor.ToAndroid(Color.FromHex("#80000000"));
#endregion
}
internal class BoxArrayAdapter : ArrayAdapter
{
private readonly IList<string> _objects;
private readonly Func<string, ICollection<string>, ICollection<string>> _sortingAlgorithm;
public BoxArrayAdapter(
Context context,
int textViewResourceId,
List<string> objects,
Func<string, ICollection<string>, ICollection<string>> sortingAlgorithm) : base(context, textViewResourceId, objects)
{
_objects = objects;
_sortingAlgorithm = sortingAlgorithm;
}
public override Filter Filter
{
get
{
return new CustomFilter(_sortingAlgorithm) { Adapter = this, Originals = _objects };
}
}
}
internal class CustomFilter : Filter
{
private readonly Func<string, ICollection<string>, ICollection<string>> _sortingAlgorithm;
public CustomFilter(Func<string, ICollection<string>, ICollection<string>> sortingAlgorithm)
{
_sortingAlgorithm = sortingAlgorithm;
}
public BoxArrayAdapter Adapter { private get; set; }
public IList<string> Originals { get; set; }
protected override FilterResults PerformFiltering(ICharSequence constraint)
{
var results = new FilterResults();
if (constraint == null || constraint.Length() == 0)
{
results.Values = new Java.Util.ArrayList(Originals.ToList());
results.Count = Originals.Count;
}
else
{
var values = new Java.Util.ArrayList();
var sorted = _sortingAlgorithm(constraint.ToString(), Originals).ToList();
for (var index = 0; index < sorted.Count; index++)
{
var item = sorted[index];
values.Add(item);
}
results.Values = values;
results.Count = sorted.Count;
}
return results;
}
protected override void PublishResults(ICharSequence constraint, FilterResults results)
{
if (results.Count == 0)
Adapter.NotifyDataSetInvalidated();
else
{
Adapter.Clear();
var vals = (Java.Util.ArrayList)results.Values;
foreach (var val in vals.ToArray())
{
Adapter.Add(val);
}
Adapter.NotifyDataSetChanged();
}
}
}
}
how can i get rid of that tooltip or placeholder and make the text in middle

How to pass json data in xamarin forms web view android side

I am using xamarin forms webview and want to pass username and password json body with url like below.
I Implement Hybrid webview in xamarin forms
My PCL Code:
public class HybridWebView : WebView
{
Action<string> action;
public EventHandler<bool> WebNavigating;
public void RegisterAction (Action<string> callback)
{
action = callback;
}
public void Cleanup ()
{
action = null;
}
public void InvokeAction (string data)
{
if (action == null || string.IsNullOrEmpty(data)) {
return;
}
action.Invoke (data);
}
}
My Android HybridWebViewRenderer Code :
public class HybridWebViewRenderer : ViewRenderer<HybridWebView, Android.Webkit.WebView>
{
Context _context;
public HybridWebViewRenderer(Context context) : base(context)
{
_context = context;
}
protected override void OnElementChanged(ElementChangedEventArgs<HybridWebView> e)
{
base.OnElementChanged(e);
if (Control == null)
{
var webView = new Android.Webkit.WebView(_context);
webView.Settings.JavaScriptEnabled = true;
webView.SetWebViewClient(new MyWebViewClient(webView,e,this));
SetNativeControl(webView);
}
}
}
public class MyWebViewClient : WebViewClient
{
const string JavaScriptFunction = "function invokeCSharpAction(data){jsBridge.invokeAction(data);}";
public Android.Webkit.WebView _webView;
public Android.Webkit.WebView WebView
{
get
{
return _webView;
}
}
public ElementChangedEventArgs<HybridWebView> _element;
public MyWebViewClient(Android.Webkit.WebView view, ElementChangedEventArgs<HybridWebView> element, HybridWebViewRenderer x)
{
_webView = view;
_element = element;
if (_element.OldElement != null)
{
_webView.RemoveJavascriptInterface("jsBridge");
var hybridWebView = _element.OldElement as HybridWebView;
hybridWebView.Cleanup();
}
if (_element.NewElement != null)
{
_webView.AddJavascriptInterface(new JSBridge(x), "jsBridge");
string url = "https://Myspecific.com/Account/MobileLogin";
string postData = "{\"UserName\":\"User1\",\"Password\":\"pass123\",\"RememberMe\":false}";
_webView.PostUrl(url, Encoding.UTF8.GetBytes(postData));
}
}
output:
It shows wrong username and password
Please help...
Thanks in advance...

Xamarin.Android ButtonRenderer longclick and touch

I'm trying to implement the functionality of the android button through a ButtonRender. The problem occurs when I try to join ".LongClick" and ".touch", since it does not launch the long click event.
protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.Button> e)
{
this.SetBackgroundResource(Resource.Drawable.button);
base.OnElementChanged(e);
Android.Widget.Button thisButton = Control as Android.Widget.Button;
thisButton.LongClickable = true;
thisButton.LongClick += delegate
{
string s = "";
};
thisButton.Touch += (object sender, Android.Views.View.TouchEventArgs e2) =>
{
if (e2.Event.Action == MotionEventActions.Down)
{
.
.
.
}
else if (e2.Event.Action == MotionEventActions.Up)
{
.
.
.
}
else if (e2.Event.Action == MotionEventActions.HoverExit || e2.Event.Action == MotionEventActions.Cancel)
{
.
.
.
}
else if (e2.Event.Action == MotionEventActions.Move)
{
.
.
.
}
};
}
To invoke the event of native control, we need to create event handlers in our custom control, and together an interface which inherits from IViewController in order to set values from renderers.
Here is my demo, first of all, create a custom button:
public class MyButton : Xamarin.Forms.Button, IMyButtonController
{
public event EventHandler Touched;
void IMyButtonController.SendTouched()
{
Touched?.Invoke(this, EventArgs.Empty);
}
public event EventHandler LongClicked;
void IMyButtonController.SendLongClicked()
{
LongClicked?.Invoke(this, EventArgs.Empty);
}
public event EventHandler Released;
void IMyButtonController.SendReleased()
{
Released?.Invoke(this, EventArgs.Empty);
}
}
The IMyButtonController inherits from IViewController like this:
public interface IMyButtonController : IViewController
{
void SendTouched();
void SendLongClicked();
void SendReleased();
}
Then in android project, implement the ButtonRenderer and IMyButtonController like this:
[assembly: ExportRenderer(typeof(MyButton), typeof(MyButtonRenderer))]
namespace ProjectNameSpace.Droid
{
public class MyButtonRenderer : Xamarin.Forms.Platform.Android.ButtonRenderer
{
protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.Button> e)
{
base.OnElementChanged(e);
if (e.NewElement != null)
{
if (Control != null)
{
Control.SetOnTouchListener(ButtonTouchListener.Instance.Value);
Control.LongClickable = true;
Control.SetOnLongClickListener(ButtonLongClickListener.Instance.Value);
}
}
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (Control != null)
{
Control.SetOnTouchListener(null);
Control.SetOnLongClickListener(null);
}
}
base.Dispose(disposing);
}
private class ButtonTouchListener : Java.Lang.Object, Android.Views.View.IOnTouchListener
{
public static readonly Lazy<ButtonTouchListener> Instance = new Lazy<ButtonTouchListener>(() => new ButtonTouchListener());
public bool OnTouch(Android.Views.View v, Android.Views.MotionEvent e)
{
var renderer = v.Tag as ButtonRenderer;
if (renderer != null)
{
var buttonController = renderer.Element as IMyButtonController;
if (e.Action == Android.Views.MotionEventActions.Down)
{
buttonController?.SendTouched();
}
else if (e.Action == Android.Views.MotionEventActions.Up)
{
buttonController?.SendReleased();
}
}
return false;
}
}
private class ButtonLongClickListener : Java.Lang.Object, Android.Views.View.IOnLongClickListener
{
public static readonly Lazy<ButtonLongClickListener> Instance = new Lazy<ButtonLongClickListener>(() => new ButtonLongClickListener());
public bool OnLongClick(Android.Views.View v)
{
var renderer = v.Tag as ButtonRenderer;
((IMyButtonController)renderer?.Element)?.SendLongClicked();
return true;
}
}
}
}

Xamarin Forms: Keyboard didn't hide

The keyboard hides when I create the page, but when I change the focus to another entry I call the same function but the soft keyboard didn't hide?
ConfigService.cs
public void HideKeyboard()
{
var inputMethodManager = Xamarin.Forms.Forms.Context.GetSystemService(Context.InputMethodService) as InputMethodManager;
if (inputMethodManager != null && Xamarin.Forms.Forms.Context is Activity)
{
var activity = Xamarin.Forms.Forms.Context as Activity;
var focusedView = activity.CurrentFocus;
var token = focusedView == null ? null : focusedView.WindowToken;
inputMethodManager.HideSoftInputFromWindow(token, HideSoftInputFlags.None);
}
}
VerplaatsingPage.xaml.cs
namespace SI_Foodware.View
{
public partial class VerplaatsingPage : ContentPage
{
VerplaatsingPageViewModel vm;
public VerplaatsingPage (SubMenu subMenu)
{
InitializeComponent ();
vm = new VerplaatsingPageViewModel(this, subMenu);
BindingContext = vm;
}
public void OnClickDestination(object o, EventArgs e)
{
}
public void OnClickSelect(object o, EventArgs e)
{
}
public void OnClickCancel(object o, EventArgs e)
{
}
protected override void OnAppearing()
{
base.OnAppearing();
ent_drager.Focus();
IConfigService configService = DependencyService.Get<IConfigService>();
configService.HideKeyboard();
}
}
}
VerplaatsingPageViewModel.cs
public void Keyboard()
{
IConfigService configService = DependencyService.Get<IConfigService>();
configService.HideKeyboard();
}
public void OnScan(string scanProperty)
{
var list = db.GetAllItems<ContainerLine>();
Artikel = list[0].ItemNo;
Description = list[0].Description;
LotNo = list[0].LotNo;
NumberOfContainer = list[0].Quantity;
KiloDrager = list[0].KgQuantity;
UnitOfMeasure = list[0].UnitofMeasureCode;
LocationFrom = list[0].BinCode;
cp.FindByName<Entry>("ent_destination").Focus();
Keyboard(); <-- Doesn't Work
}
I solved my problem by using
inputMethodManager.ToggleSoftInputFromWindow(token, ShowSoftInputFlags.None, HideSoftInputFlags.None);
instead of
inputMethodManager.HideSoftInputFromWindow(token, HideSoftInputFlags.None);

Android - Xamarin - Fused Location

I am trying to implement a custom activity that initialises the Fused Location services in Xamarin c# so I can reuse this activity whenever the Fused Location is needed. The problem that I am having is that the map is being loaded before the location services. This way, I cannot animate the camera to zoom in at the user's location since the location is still null.
Here is the custom activity:
using System;
using Android.App;
using Android.Gms.Common;
using Android.Gms.Common.Apis;
using Android.Gms.Maps.Model;
using Android.Locations;
using Android.OS;
using Android.Gms.Location;
using Android.Widget;
namespace Maps.Droid.LocationService {
public class LocationTrackerActivity : Activity, GoogleApiClient.IConnectionCallbacks, GoogleApiClient.IOnConnectionFailedListener, Android.Gms.Location.ILocationListener {
// Static Fields
public static long MIN_DISTANCE_CHANGE_FOR_UPDATES = 5; // 5 meters
public static long MIN_TIME_BW_UPDATES = 1000 * 10; // 10 seconds
private Location currentLocation;
private Activity activity;
private bool hasGooglePlayServices;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private bool locationAvailable = false;
protected override void OnCreate(Bundle savedInstanceState) {
base.OnCreate(savedInstanceState);
this.activity = this;
hasGooglePlayServices = checkPlayServices();
if (hasGooglePlayServices) {
initFusedLocation();
} else {
initAndroidLocation();
}
}
private void initFusedLocation() {
mLocationRequest = new LocationRequest();
mLocationRequest.SetInterval(LocationTrackerActivity.MIN_TIME_BW_UPDATES);
mLocationRequest.SetFastestInterval(LocationTrackerActivity.MIN_TIME_BW_UPDATES / 2);
mLocationRequest.SetSmallestDisplacement(LocationTrackerActivity.MIN_DISTANCE_CHANGE_FOR_UPDATES);
mLocationRequest.SetPriority(LocationRequest.PriorityHighAccuracy);
mGoogleApiClient = new GoogleApiClient.Builder(Application.Context)
.AddConnectionCallbacks(this)
.AddOnConnectionFailedListener(this)
.AddApi(LocationServices.API)
.Build();
}
protected override void OnResume() {
base.OnResume();
if (mGoogleApiClient.IsConnected) {
LocationServices.FusedLocationApi.RequestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
protected override void OnPause() {
base.OnPause();
// Stop location updates to save battery, but don't disconnect the GoogleApiClient object.
if (mGoogleApiClient.IsConnected) {
LocationServices.FusedLocationApi.RemoveLocationUpdates(mGoogleApiClient, this);
}
}
protected override void OnStart() {
base.OnStart();
mGoogleApiClient.Connect();
}
protected override void OnStop() {
base.OnStop();
// only stop if it's connected, otherwise we crash
if (mGoogleApiClient != null) {
mGoogleApiClient.Disconnect();
}
}
private void initAndroidLocation() {
}
private bool checkPlayServices() {
GoogleApiAvailability apiAvailability = GoogleApiAvailability.Instance;
int resultCode = apiAvailability.IsGooglePlayServicesAvailable(activity);
if (resultCode != ConnectionResult.Success) {
// In case we want to tell the user to install or update Google Play Services
//if (apiAvailability.IsUserResolvableError(resultCode)) {
// apiAvailability.GetErrorDialog(activity, resultCode, PLAY_SERVICES_RESOLUTION_REQUEST).Show();
//} else {
// Toast.MakeText(activity, "This device is not supported", ToastLength.Long).Show();
//}
return false;
}
return true; // has google play services installed
}
public double getLatitude() {
return currentLocation == null ? 0.0 : currentLocation.Latitude;
}
public double getLongitude() {
return currentLocation == null ? 0.0 : currentLocation.Longitude;
}
public bool canGetLocation() {
return locationAvailable;
}
public LatLng getLatLng() {
return new LatLng(currentLocation.Latitude, currentLocation.Longitude);
}
public void OnConnected(Bundle connectionHint) {
// Get last known recent location. If the user launches the activity,
// moves to a new location, and then changes the device orientation, the original location
// is displayed as the activity is re-created.
if (currentLocation == null && mGoogleApiClient.IsConnected) {
currentLocation = LocationServices.FusedLocationApi.GetLastLocation(mGoogleApiClient);
}
Console.WriteLine("location is about to be set to true");
locationAvailable = true;
LocationServices.FusedLocationApi.RequestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
public void OnConnectionSuspended(int cause) {
// GoogleApiClient will automatically attempt to restore the connection.
// Applications should disable UI components that require the service, and wait for a call to onConnected(Bundle) to re-enable them
if (cause == GoogleApiClient.ConnectionCallbacks.CauseServiceDisconnected) {
Toast.MakeText(activity, "Location Services disconnected. Please re-connect.", ToastLength.Long).Show();
} else if (cause == GoogleApiClient.ConnectionCallbacks.CauseNetworkLost) {
Toast.MakeText(activity, "Network lost. Please re-connect.", ToastLength.Long).Show();
}
}
public void OnConnectionFailed(ConnectionResult result) {
Console.WriteLine("Connection failed: " + result.ToString());
}
public void OnLocationChanged(Location location) {
currentLocation = location;
}
}
}
Here is the class that inherit the custom class:
using Android.App;
using Android.OS;
using Maps.Droid.LocationService;
namespace Maps.Droid {
[Activity(Label = "Map Activity")]
public class MapActivity : LocationTrackerActivity {
// Properties
protected override void OnCreate(Bundle savedInstanceState) {
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.map_activity);
var mapFrag = new MapViewFragment();
var ft = FragmentManager.BeginTransaction();
ft.Add(Resource.Id.map_container, mapFrag);
ft.Commit();
}
}
}
Here is the fragment in the inherited activity:
using System;
using Android.App;
using Android.OS;
using Android.Views;
using Android.Gms.Maps;
namespace Maps.Droid {
public class MapViewFragment : Fragment, IOnMapReadyCallback {
// private Activity activity;
private GoogleMap map;
private MapActivity parent;
public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.Inflate(Resource.Layout.map_fragment, null);
parent = ((MapActivity)Activity);
MapFragment frag = this.FragmentManager.FindFragmentById<MapFragment>(Resource.Id.map);
frag.GetMapAsync(this);
return view;
}
public void OnMapReady(GoogleMap googleMap) {
if (googleMap != null) {
map = googleMap;
var zoomVariance = 0.2;
var defaultZoom = 16f;
var currentZoomLevel = map.CameraPosition.Zoom;
map.MapType = GoogleMap.MapTypeNormal;
map.MyLocationEnabled = true;
map.CameraChange += delegate (object sender, GoogleMap.CameraChangeEventArgs e) {
if (Math.Abs(e.Position.Zoom - currentZoomLevel) < zoomVariance) {
return;
}
currentZoomLevel = e.Position.Zoom;
Console.WriteLine("Zooming " + currentZoomLevel);
};
map.UiSettings.ZoomControlsEnabled = true;
map.UiSettings.CompassEnabled = true;
map.UiSettings.SetAllGesturesEnabled(true); // Zoom, Tilt, Scroll, Rotate
if (parent.canGetLocation()) {
// ***** PROBLEM HERE ******* canGetLocation is set to true just afterwards.
map.AnimateCamera(CameraUpdateFactory.NewLatLngZoom(parent.getLatLng(), defaultZoom)); // Mosaic coordinates
}
}
}
}
}
I was thinking of implementing a call back to LocationTrackerActivity. So when the location services become available the class MapActivity then would be able to load the MapViewFragment within that custom callback. This way the location services would be loaded before the map. Therefore, this part of the code would always execute :
if (parent.canGetLocation()) {
// ***** PROBLEM HERE ******* canGetLocation is set to true just afterwards.
map.AnimateCamera(CameraUpdateFactory.NewLatLngZoom(parent.getLatLng(), defaultZoom)); // Mosaic coordinates
}
However I have no idea how to customise a callback. Maybe there are better solutions to this problem?
The problem can be because of OnConnected method. That's my OnConnected method for FusedLocationProvider in Xamarin. You can take a look on it.
public async void OnConnected(Bundle bundle)
{
Location location = LocationServices.FusedLocationApi.GetLastLocation(apiClient);
if (location != null)
{
latitude = location.Latitude;
longitude = location.Longitude;
locRequest.SetPriority(100);
locRequest.SetFastestInterval(500);
locRequest.SetInterval(1000);
await LocationServices.FusedLocationApi.RequestLocationUpdates(apiClient, locRequest, this);
}
}
When it is connected, i set the latitude and longitude values. Then in my onMapReady method, i create a new LatLng variable with these latitude and longitude variables.
void IOnMapReadyCallback.OnMapReady(GoogleMap myMap)
{
this.myMap = myMap;
myMarker = new MarkerOptions();
locCoordinates = new LatLng(latitude, longitude);
myMap.MapType = GoogleMap.MapTypeNormal;
myMap.UiSettings.ZoomControlsEnabled = true;
myMap.AnimateCamera(CameraUpdateFactory.NewLatLngZoom(locCoordinates, 10));
}
UPDATE:
I have managed to find a solution. If the user has google play services then use FusedLocation Services, if the user does not then we use Android Location Services. Then we only have to interact with one object of the type LocationTracker and everything is done by this interface:
namespace Maps.Droid.LocationService {
public interface LocationInterface {
void startLocationServices();
void stopLocationServices();
void pauseLocationServices();
void resumeLocationServices();
double getLatitude();
double getLongitude();
bool canGetLocation();
}
}
using System;
using Android.App;
using Android.Gms.Location;
using Android.Gms.Common.Apis;
using Android.OS;
using Android.Gms.Maps.Model;
using Android.Widget;
using Android.Locations;
using Android.Gms.Common;
using Android.Gms.Maps;
namespace Maps.Droid.LocationService {
public class FusedLocation : Java.Lang.Object, GoogleApiClient.IConnectionCallbacks, GoogleApiClient.IOnConnectionFailedListener, Android.Gms.Location.ILocationListener {
private Activity activity;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private Location currentLocation;
private bool locationAvailable = false;
private GoogleMap map;
public FusedLocation(Activity activity) {
this.activity = activity;
mLocationRequest = new LocationRequest();
mLocationRequest.SetInterval(LocationTracker.MIN_TIME_BW_UPDATES);
mLocationRequest.SetFastestInterval(LocationTracker.MIN_TIME_BW_UPDATES / 2);
mLocationRequest.SetSmallestDisplacement(LocationTracker.MIN_DISTANCE_CHANGE_FOR_UPDATES);
mLocationRequest.SetPriority(LocationRequest.PriorityHighAccuracy);
mGoogleApiClient = new GoogleApiClient.Builder(Application.Context)
.AddConnectionCallbacks(this)
.AddOnConnectionFailedListener(this)
.AddApi(LocationServices.API)
.Build();
}
public Location getCurrentLocation() {
return currentLocation;
}
public void setMap(GoogleMap map) {
this.map = map;
}
public double getLatitude() {
return currentLocation.Latitude;
}
public double getLongitude() {
return currentLocation.Longitude;
}
public void OnResume() {
if (mGoogleApiClient.IsConnected) {
LocationServices.FusedLocationApi.RequestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
public void OnPause() {
// Stop location updates to save battery, but don't disconnect the GoogleApiClient object.
if (mGoogleApiClient.IsConnected) {
LocationServices.FusedLocationApi.RemoveLocationUpdates(mGoogleApiClient, this);
}
}
public void OnStart() {
mGoogleApiClient?.Connect();
}
public void OnStop() {
// only stop if it's connected, otherwise we crash
if (mGoogleApiClient.IsConnected) {
mGoogleApiClient?.Disconnect();
}
}
public LatLng getLatLng() {
return new LatLng(currentLocation.Latitude, currentLocation.Longitude);
}
public bool canGetLocation() {
return locationAvailable && currentLocation != null;
}
public void OnConnected(Bundle connectionHint) {
// Get last known recent location. If the user launches the activity,
// moves to a new location, and then changes the device orientation, the original location
// is displayed as the activity is re-created.
currentLocation = LocationServices.FusedLocationApi.GetLastLocation(mGoogleApiClient);
if (currentLocation != null) {
locationAvailable = true;
LocationServices.FusedLocationApi.RequestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
if (map != null) {
map.AnimateCamera(CameraUpdateFactory.NewLatLngZoom(getLatLng(), LocationTracker.DEFAULT_ZOOM));
}
}
}
public void OnConnectionSuspended(int cause) {
// GoogleApiClient will automatically attempt to restore the connection.
// Applications should disable UI components that require the service, and wait for a call to onConnected(Bundle) to re-enable them
if (cause == GoogleApiClient.ConnectionCallbacks.CauseServiceDisconnected) {
Toast.MakeText(activity, "Location Services disconnected. Please re-connect.", ToastLength.Long).Show();
} else if (cause == GoogleApiClient.ConnectionCallbacks.CauseNetworkLost) {
Toast.MakeText(activity, "Network lost. Please re-connect.", ToastLength.Long).Show();
}
}
public void OnLocationChanged(Location location) {
currentLocation = location;
}
public void OnConnectionFailed(ConnectionResult result) {
Console.WriteLine("Connection failed: " + result.ToString());
}
}
}
using System;
using Android.OS;
using Android.Locations;
using Android.Runtime;
using Android.App;
using Android.Content;
using Android.Widget;
using Android.Gms.Maps.Model;
using Java.Util.Concurrent;
namespace Maps.Droid.LocationService {
public class AndroidLocation : Java.Lang.Object, ILocationListener {
// Properties
private LocationManager locMgr;
private Activity activity;
private Location locationGPS, locationNetwork/*, locationPassive*/, currentLocation;
private bool locationAvailable = false;
private Android.Gms.Maps.GoogleMap map;
// UNCOMMNET
// private bool isPassiveEnabled = false; // Gets location from other apps that uses Location Services
// Initializer method (Constructor). Call this method onCreate
public AndroidLocation(Activity activity) {
this.activity = activity;
getLocation();
}
public Location getCurrentLocation() {
return currentLocation;
}
public void setMap(Android.Gms.Maps.GoogleMap map) {
this.map = map;
}
private Location getLocation() {
// Use Standard Android Location Service Provider
try {
locMgr = activity.GetSystemService(Context.LocationService) as LocationManager;
bool isGPSEnabled = locMgr.IsProviderEnabled(LocationManager.GpsProvider);
// Varying precision, Less power consuming. Combination of WiFi and Cellular data
bool isNetworkEnabled = locMgr.IsProviderEnabled(LocationManager.NetworkProvider);
// UNCOMMENT
// bool isPassiveEnabled = locMgr.IsProviderEnabled(LocationManager.GpsProvider);
// UNCOMMNET
//if (isPassiveEnabled) {
// locMgr.RequestLocationUpdates(LocationManager.PassiveProvider, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
// locationPassive = locMgr.GetLastKnownLocation(LocationManager.PassiveProvider);
//}
if (isGPSEnabled) {
locMgr.RequestLocationUpdates(LocationManager.GpsProvider, LocationTracker.MIN_TIME_BW_UPDATES, LocationTracker.MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
locationGPS = locMgr?.GetLastKnownLocation(LocationManager.GpsProvider);
}
if (isNetworkEnabled) {
locMgr.RequestLocationUpdates(LocationManager.NetworkProvider, LocationTracker.MIN_TIME_BW_UPDATES, LocationTracker.MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
locationNetwork = locMgr?.GetLastKnownLocation(LocationManager.NetworkProvider);
}
// UNCOMMENT - Method must be implement if PassiveLocation is to be used
// currentLocation = getBestLocation(locationGPS, locationNetwork, locationPassive);
currentLocation = getBestLocation(locationNetwork, locationGPS);
if (currentLocation != null) {
locationAvailable = true;
if (map != null) {
map.AnimateCamera(Android.Gms.Maps.CameraUpdateFactory.NewLatLngZoom(getLatLng(), LocationTracker.DEFAULT_ZOOM));
}
}
} catch (Exception e) {
Console.WriteLine("ERROR: getLocation() " + e.ToString());
}
return currentLocation;
}
// Determines the most recent and/or most accurate location
private Location getBestLocation(Location loc1, Location loc2) {
if (loc1 == null || loc2 == null) {
return loc1 ?? loc2; // If either location is null then return the not null location
}
long time1 = TimeUnit.Milliseconds.ToSeconds(loc1.Time);
long time2 = TimeUnit.Milliseconds.ToSeconds(loc2.Time);
long twiceUpdate = (LocationTracker.MIN_TIME_BW_UPDATES / 1000) * 2;
if (Math.Abs(time1 - time2) > twiceUpdate) { // If location times are more than twiceUpdate apart
if (time1 > time2) { // More time value, most current time
return loc1;
} else {
return loc2;
}
} else {
float accuracy1 = loc1.Accuracy;
float accuracy2 = loc2.Accuracy;
// Smaller the value (meters), the greater the accuracy
if (accuracy1 < accuracy2) {
return loc1;
} else {
return loc2;
}
}
}
public void OnStop() {
locMgr = null;
}
public void OnPause() {
locMgr?.RemoveUpdates(this);
}
public void OnStart() {
}
public void OnResume() {
if (locMgr == null || currentLocation == null) {
getLocation();
}
}
public bool canGetLocation() {
return locationAvailable;
}
public LatLng getLatLng() {
return new LatLng(currentLocation.Latitude, currentLocation.Longitude);
}
public double getLatitude() {
return currentLocation.Latitude;
}
public double getLongitude() {
return currentLocation.Longitude;
}
public void OnLocationChanged(Location location) {
currentLocation = getBestLocation(currentLocation, location);
}
// User disabled a provider
public void OnProviderDisabled(string provider) {
getLocation(); // Check if all providers are disabled and pop up alertDialog if they are so
}
// User enabled a provider
public void OnProviderEnabled(string provider) {
getLocation(); // Update all available providers for getting the best provider available
}
public void OnStatusChanged(string provider, [GeneratedEnum] Availability status, Bundle extras) {
}
}
}
using Android.App;
using Android.Gms.Common;
using Android.Gms.Common.Apis;
using Android.Gms.Maps.Model;
using Android.Gms.Maps;
using Android.Locations;
using Android.Content;
using Android.Widget;
namespace Maps.Droid.LocationService {
public class LocationTracker {
public static long MIN_DISTANCE_CHANGE_FOR_UPDATES = 5; // 5 meters
public static long MIN_TIME_BW_UPDATES = 1000 * 15; // 15 seconds ok, 5 seconds really fast, 30s slow
public static float DEFAULT_ZOOM = 16f;
private bool hasGooglePlayServices;
public GoogleApiClient mGoogleApiClient;
private FusedLocation fusedLocation;
private AndroidLocation androidLocation;
private bool locationIsDisabled;
public LocationTracker(Activity activity) {
if (locationIsDisabled = isLocationDisabled(activity)) {
showSettingsAlert(activity);
} else {
hasGooglePlayServices = checkPlayServices(activity);
if (hasGooglePlayServices) {
fusedLocation = new FusedLocation(activity);
} else {
androidLocation = new AndroidLocation(activity);
}
}
}
private void showSettingsAlert(Activity activity) {
AlertDialog.Builder builder = new AlertDialog.Builder(activity);
builder.SetTitle("Location Services Not Active");
builder.SetMessage("Please enable Location Services and GPS");
builder.SetPositiveButton("OK", delegate {
// Show location settings when the user acknowledges the alert dialog
var intent = new Intent(Android.Provider.Settings.ActionLocationSourceSettings);
activity.StartActivity(intent);
});
builder.SetNegativeButton("Cancel", delegate {
Toast.MakeText(activity, "Location disabled by user", ToastLength.Short).Show();
});
AlertDialog alertDialog = builder.Create();
alertDialog.SetCanceledOnTouchOutside(false);
alertDialog.Show();
}
private bool isLocationDisabled(Activity activity) {
LocationManager locMgr = activity.GetSystemService(Context.LocationService) as LocationManager;
// More precise, More power consuming
bool isGPSEnabled = locMgr.IsProviderEnabled(LocationManager.GpsProvider);
// Varying precision, Less power consuming. Combination of WiFi and Cellular data
bool isNetworkEnabled = locMgr.IsProviderEnabled(LocationManager.NetworkProvider);
// UNCOMMENT
// bool isPassiveEnabled = locMgr.IsProviderEnabled(LocationManager.PassiveProvider);
// UNCOMMENT
// return !isGPSEnabled && !isNetworkEnabled && !isPassiveEnabled; // True only when the 3 location services are disabled
return !isGPSEnabled && !isNetworkEnabled; // True only when both location services are disabled
}
// Call this method at OnMapReady callback if initial zooming/animation on user's location is desired
public void setMap(GoogleMap map) {
if (locationIsDisabled) {
return;
}
if (hasGooglePlayServices) {
fusedLocation.setMap(map);
} else {
androidLocation.setMap(map);
}
}
public void OnResume() {
if (locationIsDisabled) {
return;
}
if (hasGooglePlayServices) {
fusedLocation.OnResume();
} else {
androidLocation.OnResume();
}
}
public void OnPause() {
if (locationIsDisabled) {
return;
}
if (hasGooglePlayServices) {
fusedLocation.OnPause();
} else {
androidLocation.OnPause();
}
}
public void OnStart() {
if (locationIsDisabled) {
return;
}
if (hasGooglePlayServices) {
fusedLocation.OnStart();
} else {
androidLocation.OnStart();
}
}
public void OnStop() {
if (locationIsDisabled) {
return;
}
if (hasGooglePlayServices) {
fusedLocation.OnStop();
} else {
androidLocation.OnStop();
}
}
private bool checkPlayServices(Activity activity) {
GoogleApiAvailability apiAvailability = GoogleApiAvailability.Instance;
int resultCode = apiAvailability.IsGooglePlayServicesAvailable(activity);
if (resultCode == ConnectionResult.Success) {
return true;
}
return false;
}
public double getLatitude() {
if (locationIsDisabled) {
return 0;
}
if (hasGooglePlayServices) {
return fusedLocation.getCurrentLocation() == null ? 0.0 : fusedLocation.getLatitude();
} else {
return androidLocation.getCurrentLocation() == null ? 0.0 : androidLocation.getLatitude();
}
}
public double getLongitude() {
if (locationIsDisabled) {
return 0;
}
if (hasGooglePlayServices) {
return fusedLocation.getCurrentLocation() == null ? 0.0 : fusedLocation.getLongitude();
} else {
return androidLocation.getCurrentLocation() == null ? 0.0 : androidLocation.getLongitude();
}
}
public bool canGetLocation() {
if (locationIsDisabled) {
return false;
}
if (hasGooglePlayServices) {
return fusedLocation.canGetLocation();
} else {
return androidLocation.canGetLocation();
}
}
public LatLng getLatLng() {
if (locationIsDisabled) {
return null;
}
LatLng latlng;
if (hasGooglePlayServices) {
latlng = fusedLocation.getLatLng();
} else {
latlng = androidLocation.getLatLng();
}
return latlng;
}
public Location getCurrentLocation() {
if (hasGooglePlayServices) {
return fusedLocation.getCurrentLocation();
} else {
return androidLocation.getCurrentLocation();
}
}
}
}
Then to use it on your fragment or activity:
Initialise it at OnCreate:
Location tracker = new LocationTracker(this.Activity);
make a referent for the life cycles:
public override void OnResume() {
base.OnResume();
tracker.OnResume();
}
public override void OnPause() {
base.OnPause();
tracker.OnPause();
}
public override void OnStart() {
base.OnStart();
tracker.OnStart();
}
public override void OnStop() {
base.OnStop();
tracker.OnStop();
}
if you want the animation to zoom at the users location in the beginning, then you have to add this line of code when you have the googlemap:
tracker.setMap(googleMap); // Invoke this method if zooming/animating to the user's location is desired
Spent many days on this solution. Hope it can help somebody!

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