Java lang nullpointerexception xamarin

Null Pointer Exception Constructors

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Overloads

Constructs a NullPointerException with no detail message.

Constructs a NullPointerException with the specified detail message.

A constructor used when creating managed representations of JNI objects; called by the runtime.

NullPointerException()

Constructs a NullPointerException with no detail message.

[Android.Runtime.Register(".ctor", "()V", "")] public NullPointerException ();

Remarks

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to

NullPointerException(String)

Constructs a NullPointerException with the specified detail message.

[Android.Runtime.Register(".ctor", "(Ljava/lang/String;)V", "")] public NullPointerException (string? s);

[] new Java.Lang.NullPointerException : string -> Java.Lang.NullPointerException

Parameters

Remarks

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to

NullPointerException(IntPtr, JniHandleOwnership)

A constructor used when creating managed representations of JNI objects; called by the runtime.

protected NullPointerException (IntPtr javaReference, Android.Runtime.JniHandleOwnership transfer);

new Java.Lang.NullPointerException : nativeint * Android.Runtime.JniHandleOwnership -> Java.Lang.NullPointerException

Parameters

A IntPtrcontaining a Java Native Interface (JNI) object reference.

A JniHandleOwnershipindicating how to handle javaReference

Remarks

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

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Null Pointer Exception Class

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Thrown when an application attempts to use null in a case where an object is required.

[Android.Runtime.Register("java/lang/NullPointerException", DoNotGenerateAcw=true)] public class NullPointerException : Java.Lang.RuntimeException

[] type NullPointerException = class inherit RuntimeException

Remarks

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Constructors

Constructs a NullPointerException with no detail message.

A constructor used when creating managed representations of JNI objects; called by the runtime.

Constructs a NullPointerException with the specified detail message.

Fields

Properties

Returns the cause of this throwable or null if the cause is nonexistent or unknown.

The handle to the underlying Android instance.

Creates a localized description of this throwable.

Returns the detail message string of this throwable.

This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

This API supports the Mono for Android infrastructure and is not intended to be used directly from your code.

Methods

Appends the specified exception to the exceptions that were suppressed in order to deliver this exception.

Fills in the execution stack trace.

Provides programmatic access to the stack trace information printed by #printStackTrace() .

Returns an array containing all of the exceptions that were suppressed, typically by the try -with-resources statement, in order to deliver this exception.

Initializes the cause of this throwable to the specified value.

Prints this throwable and its backtrace to the standard error stream.

Prints this throwable and its backtrace to the specified print stream.

Prints this throwable and its backtrace to the specified print writer.

Sets the stack trace elements that will be returned by #getStackTrace() and printed by #printStackTrace() and related methods.

Explicit Interface Implementations

IJavaPeerable.Disposed()	(Inherited from Throwable)
IJavaPeerable.DisposeUnlessReferenced()	(Inherited from Throwable)
IJavaPeerable.Finalized()	(Inherited from Throwable)
IJavaPeerable.JniManagedPeerState	(Inherited from Throwable)
IJavaPeerable.SetJniIdentityHashCode(Int32)	(Inherited from Throwable)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates)	(Inherited from Throwable)
IJavaPeerable.SetPeerReference(JniObjectReference)	(Inherited from Throwable)

Extension Methods

Performs an Android runtime-checked type conversion.

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Java lang nullpointerexception xamarin

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Question

User133445 posted
After June 2nd Xamarin platform update I’m getting NullPointerException, when AppCompatActivity starts. Workaround is to use older version of Xamarin.Android. But I wanna know what’s wrong. [MonoDroid] UNHANDLED EXCEPTION: [MonoDroid] Java.Lang.NullPointerException: Exception of type ‘Java.Lang.NullPointerException’ was thrown. [MonoDroid] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [MonoDroid] at Android.Runtime.JNIEnv.CallNonvirtualVoidMethod (intptr,intptr,intptr,Android.Runtime.JValue*) [0x00084] in /Users/builder/data/lanes/monodroid-mavericks-monodroid-5.1-series/d419c934/source/monodroid/src/Mono.Android/src/Runtime/JNIEnv.g.cs:1029 [MonoDroid] at Android.App.Activity.SetContentView (int) [0x00070] in /Users/builder/data/lanes/monodroid-mavericks-monodroid-5.1-series/d419c934/source/monodroid/src/Mono.Android/platforms/android-21/src/generated/Android.App.Activity.cs:5466 [MonoDroid] at Divvy.Android.UI.Activities.SplashActivity.OnCreate (Android.OS.Bundle) [0x00009] in d:\Projects\divvyMobile\Divvy.Android\UI\Activities\SplashActivity.cs:22 [MonoDroid] at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (intptr,intptr,intptr) [0x00011] in /Users/builder/data/lanes/monodroid-mavericks-monodroid-5.1-series/d419c934/source/monodroid/src/Mono.Android/platforms/android-21/src/generated/Android.App.Activity.cs:2707 [MonoDroid] at (wrapper dynamic-method) object.e2dd4570-1bf5-41c3-8251-c245e04b892f (intptr,intptr,intptr) [MonoDroid] — End of managed exception stack trace — [MonoDroid] java.lang.NullPointerException: Attempt to invoke virtual method ‘void android.support.v7.internal.widget.ContentFrameLayout.setId(int)’ on a null object reference [MonoDroid] at android.support.v7.app.AppCompatDelegateImplV7.ensureSubDecor(AppCompatDelegateImplV7.java:389) [MonoDroid] at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:246) [MonoDroid] at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:106) [MonoDroid] at md5feaba49227f182b4a9f46be73a17f454.SplashActivity.n_onCreate(Native Method) [MonoDroid] at md5feaba49227f182b4a9f46be73a17f454.SplashActivity.onCreate(SplashActivity.java:31) [MonoDroid] at android.app.Activity.performCreate(Activity.java:5990) [MonoDroid] at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106) [MonoDroid] at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278) [MonoDroid] at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) [MonoDroid] at android.app.ActivityThread.access$800(ActivityThread.java:151) [MonoDroid] at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) [MonoDroid] at android.os.Handler.dispatchMessage(Handler.java:102) [MonoDroid] at android.os.Looper.loop(Looper.java:135) [MonoDroid] at android.app.ActivityThread.main(ActivityThread.java:5254) [MonoDroid] at java.lang.reflect.Method.invoke(Native Method) [MonoDroid] at java.lang.reflect.Method.invoke(Method.java:372) [MonoDroid] at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) [MonoDroid] at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) Activity code:

[Activity(MainLauncher = true, ScreenOrientation = ScreenOrientation.Portrait, NoHistory = true, Theme="@style/AppTheme.NoActionBar")] public class SplashActivity : AppCompatActivity, IOnMapReadyCallback < protected override void OnCreate (Bundle savedInstanceState) < base.OnCreate (savedInstanceState); SetContentView (Resource.Layout.activity_splash); InitDatabase (); if (!string.IsNullOrEmpty (AccountUtils.GetCurrentUserSessionId (this))) StartActivity (typeof(HomeActivity)); else StartActivity (typeof(LoginActivity)); >> 

All replies

User83387 posted
I can firm exactly the same issue with Xamarin Studio 5.9.5 and Xamarin.Android 5.1.5 Stacktrace:

 System.Diagnostics.Debugger.Mono_UnhandledException (ex=: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.internal.widget.ContentFrameLayout.setId(int)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3119) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3218) at android.app.ActivityThread.access$1000(ActivityThread.java:198) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1676) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:145) at android.app.ActivityThread.main(ActivityThread.java:6837) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.internal.widget.ContentFrameLayout.setId(int)' on a null object reference at android.support.v7.app.AppCompatDelegateImplV7.ensureSubDecor(AppCompatDelegateImplV7.java:392) at android.support.v7.app.AppCompatDelegateImplV7.onPostCreate(AppCompatDelegateImplV7.java:166) at android.support.v7.app.AppCompatActivity.onPostCreate(AppCompatActivity.java:65) at android.app.Instrumentation.callActivityOnPostCreate(Instrumentation.java:1201) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3101) . 10 more >) in /Users/builder/data/lanes/1978/f98871a9/source/mono/mcs/class/corlib/System.Diagnostics/Debugger.cs:122 

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