Gustavo Baiocchi Costa
Reputation: 1448
FusedLocation GoogleApi - Listener must not be null (Xamarin.Android)
I am getting the following:
Java.Lang.NullPointerException: Listener must not be null.
Can't seem to get away with it. I have exhausted all possible solutions I could find.
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;
namespace Maps.Droid.LocationService {
public class FusedLocation : GoogleApiClient.IConnectionCallbacks, GoogleApiClient.IOnConnectionFailedListener, Android.Gms.Location.ILocationListener {
private Activity activity;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private Location currentLocation;
private bool locationAvailable = false;
public FusedLocation(Activity activity) {
this.activity = activity;
setGoogleApiClient();
setLocationRequest();
//var requestBuilder = new LocationSettingsRequest.Builder().AddLocationRequest(mLocationRequest);
//requestBuilder.SetAlwaysShow(true);
// Next check whether the current location settings are satisfied:
//var result = LocationServices.SettingsApi.CheckLocationSettings(mGoogleApiClient, requestBuilder.Build());
}
private void setGoogleApiClient() {
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(activity)
.AddConnectionCallbacks(this)
.AddOnConnectionFailedListener(this)
.AddApi(LocationServices.API)
.Build();
}
}
private void setLocationRequest() {
if (mLocationRequest == null) {
mLocationRequest = new LocationRequest();
mLocationRequest.SetInterval(LocationTracker.MIN_TIME_BW_UPDATES);
mLocationRequest.SetFastestInterval(LocationTracker.MIN_TIME_BW_UPDATES / 2);
mLocationRequest.SetPriority(LocationRequest.PriorityHighAccuracy);
}
}
public LatLng getLatLng() {
return new LatLng(currentLocation.Latitude, currentLocation.Longitude);
}
public double getLatitude() {
return currentLocation == null ? 0.0 : currentLocation.Latitude;
}
public double getLongitude() {
return currentLocation == null ? 0.0 : currentLocation.Longitude;
}
public void startLocationServices() {
if (!mGoogleApiClient.IsConnected) {
mGoogleApiClient.Connect();
LocationServices.FusedLocationApi.RequestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
}
public void pauseLocationServices() {
// Stop location updates to save battery, but don't disconnect the GoogleApiClient object.
if (mGoogleApiClient.IsConnected) {
LocationServices.FusedLocationApi.RemoveLocationUpdates(mGoogleApiClient, this);
}
}
public void stopLocationServices() {
// only stop if it's connected, otherwise we crash
if (mGoogleApiClient != null) {
mGoogleApiClient.Disconnect();
}
}
public bool canGetLocation() {
return locationAvailable;
}
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) {
currentLocation = LocationServices.FusedLocationApi.GetLastLocation(mGoogleApiClient);
}
locationAvailable = true;
// Begin polling for new location updates.
startLocationUpdates();
}
// Trigger new location updates at interval
protected void startLocationUpdates() {
setGoogleApiClient(); // The method checks if it has been already initialized
setLocationRequest(); // The method checks if it has been already initialized
// Request location updates
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 OnLocationChanged(Location location) {
currentLocation = location;
}
public void OnConnectionFailed(ConnectionResult result) {
if (mGoogleApiClient != null) {
mGoogleApiClient.Connect();
}
}
public IntPtr Handle {
get;
}
public void Dispose() {
}
}
}
It seems that the problem is coming from the method setGoogleApiClient();
Check this image:
I hit continue after the error was found:
08-12 16:09:14.446 D/OpenGLRenderer(13084): Enabling debug mode 0
08-12 16:09:15.176 D/Mono (13084): Assembly Ref addref Maps.Droid[0x64b8c7f8] -> Xamarin.GooglePlayServices.Maps[0x64bdfe50]: 2
08-12 16:09:15.176 D/Mono (13084): Assembly Ref addref Maps.Droid[0x64b8c7f8] -> Xamarin.GooglePlayServices.Basement[0x64bde280]: 2
08-12 16:09:15.176 D/Mono (13084): Assembly Ref addref Maps.Droid[0x64b8c7f8] -> Xamarin.GooglePlayServices.Location[0x64bdf070]: 2
08-12 16:09:15.206 D/Mono (13084): Assembly Ref addref Xamarin.GooglePlayServices.Location[0x64bdf070] -> Xamarin.GooglePlayServices.Basement[0x64bde280]: 3
08-12 16:09:15.206 D/Mono (13084): Assembly Ref addref Maps.Droid[0x64b8c7f8] -> Xamarin.GooglePlayServices.Base[0x64bdd490]: 2
08-12 16:09:15.206 D/Mono (13084): Assembly Ref addref Xamarin.GooglePlayServices.Base[0x64bdd490] -> Xamarin.GooglePlayServices.Basement[0x64bde280]: 4
08-12 16:09:15.216 I/dalvikvm(13084): Could not find method android.content.pm.PackageManager.getPackageInstaller, referenced from method com.google.android.gms.common.zze.zzi
08-12 16:09:15.216 W/dalvikvm(13084): VFY: unable to resolve virtual method 404: Landroid/content/pm/PackageManager;.getPackageInstaller ()Landroid/content/pm/PackageInstaller;
08-12 16:09:15.216 D/dalvikvm(13084): VFY: replacing opcode 0x6e at 0x000b
08-12 16:09:15.216 D/Mono (13084): DllImport searching in: '__Internal' ('(null)').
08-12 16:09:15.216 D/Mono (13084): Searching for 'java_interop_jnienv_call_static_object_method'.
08-12 16:09:15.216 D/Mono (13084): Probing 'java_interop_jnienv_call_static_object_method'.
08-12 16:09:15.216 D/Mono (13084): Found as 'java_interop_jnienv_call_static_object_method'.
08-12 16:09:15.226 D/Mono (13084): DllImport searching in: '__Internal' ('(null)').
08-12 16:09:15.226 D/Mono (13084): Searching for 'java_interop_jnienv_call_int_method_a'.
08-12 16:09:15.226 D/Mono (13084): Probing 'java_interop_jnienv_call_int_method_a'.
08-12 16:09:15.226 D/Mono (13084): Found as 'java_interop_jnienv_call_int_method_a'.
08-12 16:09:15.336 D/Mono (13084): DllImport attempting to load: '/system/lib/liblog.so'.
08-12 16:09:15.336 D/Mono (13084): DllImport loaded library '/system/lib/liblog.so'.
08-12 16:09:15.336 D/Mono (13084): DllImport searching in: '/system/lib/liblog.so' ('/system/lib/liblog.so').
08-12 16:09:15.336 D/Mono (13084): Searching for '__android_log_print'.
08-12 16:09:15.336 D/Mono (13084): Probing '__android_log_print'.
08-12 16:09:15.336 D/Mono (13084): Found as '__android_log_print'.
08-12 16:09:15.336 I/mono-stdout(13084): 1
1
1
08-12 16:09:15.346 I/mono-stdout(13084): 1
2
2
08-12 16:09:15.346 I/mono-stdout(13084): 2
08-12 16:09:15.346 I/mono-stdout(13084): 2
08-12 16:09:15.346 D/Mono (13084): DllImport searching in: '__Internal' ('(null)').
08-12 16:09:15.346 D/Mono (13084): Searching for 'java_interop_jnienv_get_static_field_id'.
08-12 16:09:15.346 D/Mono (13084): Probing 'java_interop_jnienv_get_static_field_id'.
08-12 16:09:15.346 D/Mono (13084): Found as 'java_interop_jnienv_get_static_field_id'.
08-12 16:09:15.356 D/Mono (13084): DllImport searching in: '__Internal' ('(null)').
08-12 16:09:15.356 D/Mono (13084): Searching for 'java_interop_jnienv_get_static_object_field'.
08-12 16:09:15.356 D/Mono (13084): Probing 'java_interop_jnienv_get_static_object_field'.
08-12 16:09:15.356 D/Mono (13084): Found as 'java_interop_jnienv_get_static_object_field'.
Unhandled Exception:
Java.Lang.NullPointerException: Listener must not be null
08-12 16:09:17.826 D/Mono (13084): DllImport attempting to load: '/system/lib/liblog.so'.
08-12 16:09:17.826 D/Mono (13084): DllImport loaded library '/system/lib/liblog.so'.
08-12 16:09:17.826 D/Mono (13084): DllImport searching in: '/system/lib/liblog.so' ('/system/lib/liblog.so').
08-12 16:09:17.826 D/Mono (13084): Searching for '__android_log_print'.
08-12 16:09:17.826 D/Mono (13084): Probing '__android_log_print'.
08-12 16:09:17.836 D/Mono (13084): Found as '__android_log_print'.
08-12 16:09:17.856 I/MonoDroid(13084): UNHANDLED EXCEPTION:
08-12 16:09:17.866 I/MonoDroid(13084): Java.Lang.NullPointerException: Listener must not be null
08-12 16:09:17.866 I/MonoDroid(13084): at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Users/builder/data/lanes/3540/1cf254db/source/mono/external/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143
08-12 16:09:17.876 I/MonoDroid(13084): at Java.Interop.JniEnvironment+InstanceMethods.CallObjectMethod (JniObjectReference instance, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x00085] in /Users/builder/data/lanes/3540/1cf254db/source/Java.Interop/src/Java.Interop/Java.Interop/JniEnvironment.g.cs:11283
08-12 16:09:17.876 I/MonoDroid(13084): at Android.Runtime.JNIEnv.CallObjectMethod (IntPtr jobject, IntPtr jmethod, Android.Runtime.JValue* parms) [0x00000] in /Users/builder/data/lanes/3540/1cf254db/source/monodroid/src/Mono.Android/src/Runtime/JNIEnv.g.cs:102
08-12 16:09:17.876 I/MonoDroid(13084): at Android.Gms.Common.Apis.GoogleApiClient+Builder.AddConnectionCallbacks (IConnectionCallbacks listener) [0x0004a] in <filename unknown>:0
08-12 16:09:17.876 I/MonoDroid(13084): at Maps.Droid.LocationService.FusedLocation..ctor (Android.App.Activity activity) [0x000a0] in C:\Users\Gustavo.Costa\documents\visual studio 2015\Projects\Maps\Maps\Maps.Droid\LocationService\FusedLocation.cs:38
08-12 16:09:17.876 I/MonoDroid(13084): at Maps.Droid.LocationService.LocationTracker..ctor (Android.App.Activity activity) [0x00026] in C:\Users\Gustavo.Costa\documents\visual studio 2015\Projects\Maps\Maps\Maps.Droid\LocationService\LocationTracker.cs:22
08-12 16:09:17.876 I/MonoDroid(13084): at Maps.Droid.MapActivity.OnCreate (Android.OS.Bundle savedInstanceState) [0x00015] in C:\Users\Gustavo.Costa\documents\visual studio 2015\Projects\Maps\Maps\Maps.Droid\MapActivity.cs:15
08-12 16:09:17.876 I/MonoDroid(13084): at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (IntPtr jnienv, IntPtr native__this, IntPtr native_savedInstanceState) [0x00011] in /Users/builder/data/lanes/3540/1cf254db/source/monodroid/src/Mono.Android/platforms/android-23/src/generated/Android.App.Activity.cs:2426
08-12 16:09:17.876 I/MonoDroid(13084): at (wrapper dynamic-method) System.Object:0a7eba53-2ed2-4ace-97be-6a8e8dacad4a (intptr,intptr,intptr)
08-12 16:09:17.876 I/MonoDroid(13084): --- End of managed Java.Lang.NullPointerException stack trace ---
08-12 16:09:17.876 I/MonoDroid(13084): java.lang.NullPointerException: Listener must not be null
08-12 16:09:17.876 I/MonoDroid(13084): at com.google.android.gms.common.internal.zzx.zzb(Unknown Source)
08-12 16:09:17.876 I/MonoDroid(13084): at com.google.android.gms.common.api.GoogleApiClient$Builder.addConnectionCallbacks(Unknown Source)
08-12 16:09:17.876 I/MonoDroid(13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.n_onCreate(Native Method)
08-12 16:09:17.876 I/MonoDroid(13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.onCreate(MapActivity.java:33)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.Activity.performCreate(Activity.java:5411)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2233)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2359)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-12 16:09:17.876 I/MonoDroid(13084): at android.os.Handler.dispatchMessage(Handler.java:102)
08-12 16:09:17.876 I/MonoDroid(13084): at android.os.Looper.loop(Looper.java:136)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.main(ActivityThread.java:5230)
08-12 16:09:17.876 I/MonoDroid(13084): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 16:09:17.876 I/MonoDroid(13084): at java.lang.reflect.Method.invoke(Method.java:515)
08-12 16:09:17.876 I/MonoDroid(13084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
08-12 16:09:17.876 I/MonoDroid(13084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
08-12 16:09:17.876 I/MonoDroid(13084): at dalvik.system.NativeStart.main(Native Method)
08-12 16:09:17.876 I/MonoDroid(13084): --- End of managed Java.Lang.NullPointerException stack trace ---
08-12 16:09:17.876 I/MonoDroid(13084): java.lang.NullPointerException: Listener must not be null
08-12 16:09:17.876 I/MonoDroid(13084): at com.google.android.gms.common.internal.zzx.zzb(Unknown Source)
08-12 16:09:17.876 I/MonoDroid(13084): at com.google.android.gms.common.api.GoogleApiClient$Builder.addConnectionCallbacks(Unknown Source)
08-12 16:09:17.876 I/MonoDroid(13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.n_onCreate(Native Method)
08-12 16:09:17.876 I/MonoDroid(13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.onCreate(MapActivity.java:33)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.Activity.performCreate(Activity.java:5411)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2233)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2359)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-12 16:09:17.876 I/MonoDroid(13084): at android.os.Handler.dispatchMessage(Handler.java:102)
08-12 16:09:17.876 I/MonoDroid(13084): at android.os.Looper.loop(Looper.java:136)
08-12 16:09:17.876 I/MonoDroid(13084): at android.app.ActivityThread.main(ActivityThread.java:5230)
08-12 16:09:17.876 I/MonoDroid(13084): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 16:09:17.876 I/MonoDroid(13084): at java.lang.reflect.Method.invoke(Method.java:515)
08-12 16:09:17.876 I/MonoDroid(13084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
08-12 16:09:17.886 I/MonoDroid(13084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
08-12 16:09:17.886 I/MonoDroid(13084): at dalvik.system.NativeStart.main(Native Method)
08-12 16:09:17.886 D/Mono (13084): DllImport searching in: '__Internal' ('(null)').
08-12 16:09:17.886 D/Mono (13084): Searching for 'java_interop_jnienv_throw'.
08-12 16:09:17.886 D/Mono (13084): Probing 'java_interop_jnienv_throw'.
08-12 16:09:17.886 D/Mono (13084): Found as 'java_interop_jnienv_throw'.
An unhandled exception occured.
08-12 16:09:19.416 E/mono (13084):
08-12 16:09:19.416 E/mono (13084): Unhandled Exception:
08-12 16:09:19.416 E/mono (13084): Java.Lang.NullPointerException: Listener must not be null
08-12 16:09:19.416 E/mono (13084): at (wrapper dynamic-method) System.Object:0a7eba53-2ed2-4ace-97be-6a8e8dacad4a (intptr,intptr,intptr)
08-12 16:09:19.416 E/mono (13084): at (wrapper native-to-managed) System.Object:0a7eba53-2ed2-4ace-97be-6a8e8dacad4a (intptr,intptr,intptr)
08-12 16:09:19.416 E/mono (13084): --- End of managed Java.Lang.NullPointerException stack trace ---
08-12 16:09:19.416 E/mono (13084): java.lang.NullPointerException: Listener must not be null
08-12 16:09:19.416 E/mono (13084): at com.google.android.gms.common.internal.zzx.zzb(Unknown Source)
08-12 16:09:19.416 E/mono (13084): at com.google.android.gms.common.api.GoogleApiClient$Builder.addConnectionCallbacks(Unknown Source)
08-12 16:09:19.416 E/mono (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.n_onCreate(Native Method)
08-12 16:09:19.416 E/mono (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.onCreate(MapActivity.java:33)
08-12 16:09:19.416 E/mono (13084): at android.app.Activity.performCreate(Activity.java:5411)
08-12 16:09:19.416 E/mono (13084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2233)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2359)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-12 16:09:19.416 E/mono (13084): at android.os.Handler.dispatchMessage(Handler.java:102)
08-12 16:09:19.416 E/mono (13084): at android.os.Looper.loop(Looper.java:136)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.main(ActivityThread.java:5230)
08-12 16:09:19.416 E/mono (13084): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 16:09:19.416 E/mono (13084): at java.lang.reflect.Method.invoke(Method.java:515)
08-12 16:09:19.416 E/mono (13084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
08-12 16:09:19.416 E/mono (13084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
08-12 16:09:19.416 E/mono (13084): at dalvik.system.NativeStart.main(Native Method)
08-12 16:09:19.416 E/mono (13084):
08-12 16:09:19.416 E/mono (13084): --- End of managed Java.Lang.NullPointerException stack trace ---
08-12 16:09:19.416 E/mono (13084): java.lang.NullPointerException: Listener must not be null
08-12 16:09:19.416 E/mono (13084): at com.google.android.gms.common.internal.zzx.zzb(Unknown Source)
08-12 16:09:19.416 E/mono (13084): at com.google.android.gms.common.api.GoogleApiClient$Builder.addConnectionCallbacks(Unknown Source)
08-12 16:09:19.416 E/mono (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.n_onCreate(Native Method)
08-12 16:09:19.416 E/mono (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.onCreate(MapActivity.java:33)
08-12 16:09:19.416 E/mono (13084): at android.app.Activity.performCreate(Activity.java:5411)
08-12 16:09:19.416 E/mono (13084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2233)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2359)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-12 16:09:19.416 E/mono (13084): at android.os.Handler.dispatchMessage(Handler.java:102)
08-12 16:09:19.416 E/mono (13084): at android.os.Looper.loop(Looper.java:136)
08-12 16:09:19.416 E/mono (13084): at android.app.ActivityThread.main(ActivityThread.java:5230)
08-12 16:09:19.416 E/mono (13084): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 16:09:19.416 E/mono (13084): at java.lang.reflect.Method.invoke(Method.java:515)
08-12 16:09:19.416 E/mono (13084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
08-12 16:09:19.416 E/mono (13084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
08-12 16:09:19.416 E/mono (13084): at dalvik.system.NativeStart.main(Native Method)
08-12 16:09:19.416 E/mono (13084):
08-12 16:09:19.416 E/mono-rt (13084): [ERROR] FATAL UNHANDLED EXCEPTION: Java.Lang.NullPointerException: Listener must not be null
08-12 16:09:19.416 E/mono-rt (13084): at (wrapper dynamic-method) System.Object:0a7eba53-2ed2-4ace-97be-6a8e8dacad4a (intptr,intptr,intptr)
08-12 16:09:19.416 E/mono-rt (13084): at (wrapper native-to-managed) System.Object:0a7eba53-2ed2-4ace-97be-6a8e8dacad4a (intptr,intptr,intptr)
08-12 16:09:19.416 E/mono-rt (13084): --- End of managed Java.Lang.NullPointerException stack trace ---
08-12 16:09:19.416 E/mono-rt (13084): java.lang.NullPointerException: Listener must not be null
08-12 16:09:19.416 E/mono-rt (13084): at com.google.android.gms.common.internal.zzx.zzb(Unknown Source)
08-12 16:09:19.416 E/mono-rt (13084): at com.google.android.gms.common.api.GoogleApiClient$Builder.addConnectionCallbacks(Unknown Source)
08-12 16:09:19.416 E/mono-rt (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.n_onCreate(Native Method)
08-12 16:09:19.416 E/mono-rt (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.onCreate(MapActivity.java:33)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.Activity.performCreate(Activity.java:5411)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2233)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2359)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-12 16:09:19.416 E/mono-rt (13084): at android.os.Handler.dispatchMessage(Handler.java:102)
08-12 16:09:19.416 E/mono-rt (13084): at android.os.Looper.loop(Looper.java:136)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.main(ActivityThread.java:5230)
08-12 16:09:19.416 E/mono-rt (13084): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 16:09:19.416 E/mono-rt (13084): at java.lang.reflect.Method.invoke(Method.java:515)
08-12 16:09:19.416 E/mono-rt (13084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
08-12 16:09:19.416 E/mono-rt (13084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
08-12 16:09:19.416 E/mono-rt (13084): at dalvik.system.NativeStart.main(Native Method)
08-12 16:09:19.416 E/mono-rt (13084):
08-12 16:09:19.416 E/mono-rt (13084): --- End of managed Java.Lang.NullPointerException stack trace ---
08-12 16:09:19.416 E/mono-rt (13084): java.lang.NullPointerException: Listener must not be null
08-12 16:09:19.416 E/mono-rt (13084): at com.google.android.gms.common.internal.zzx.zzb(Unknown Source)
08-12 16:09:19.416 E/mono-rt (13084): at com.google.android.gms.common.api.GoogleApiClient$Builder.addConnectionCallbacks(Unknown Source)
08-12 16:09:19.416 E/mono-rt (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.n_onCreate(Native Method)
08-12 16:09:19.416 E/mono-rt (13084): at md551afeb14f78091b7dcc7953e9e497c49.MapActivity.onCreate(MapActivity.java:33)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.Activity.performCreate(Activity.java:5411)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2233)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2359)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.access$800(ActivityThread.java:139)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-12 16:09:19.416 E/mono-rt (13084): at android.os.Handler.dispatchMessage(Handler.java:102)
08-12 16:09:19.416 E/mono-rt (13084): at android.os.Looper.loop(Looper.java:136)
08-12 16:09:19.416 E/mono-rt (13084): at android.app.ActivityThread.main(ActivityThread.java:5230)
08-12 16:09:19.416 E/mono-rt (13084): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 16:09:19.416 E/mono-rt (13084): at java.lang.reflect.Method.invoke(Method.java:515)
08-12 16:09:19.416 E/mono-rt (13084): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:780)
08-12 16:09:19.416 E/mono-rt (13084): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:596)
08-12 16:09:19.416 E/mono-rt (13084): at dalvik.system.NativeStart.main(Native Method)
08-12 16:09:19.416 E/mono-rt (13084):
In mgmain JNI_OnLoad
Upvotes: 1
Views: 2371
Answers (1)
Gustavo Baiocchi Costa
Reputation: 1448
Find the problem. You can only implement the GoogleApiClient on the activity. Wanted to create an interface for using location services. Not possible this way!
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!
Upvotes: 1
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