我正在使用HybridWebView，每当我尝试按下Android硬件按钮时，应用程序崩溃，当我按下操作栏时，会执行预期的后退操作。
关于类似问题还有一个open issue on Git Hub，还没有任何修复。
这是我的堆栈跟踪：
at mono.java.lang.RunnableImplementor.n_run(Native method)
at mono.java.lang.RunnableImplementor.run(RunnableImplementor.java:29)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5274)
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:909)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:704)
Pending exception android.runtime.JavaProxyThrowable thrown by 'void mono.java.lang.RunnableImplementor.n_run():-2'
android.runtime.JavaProxyThrowable: System.NullReferenceException: Object reference not set to an instance of an object
(22346): art/runtime/runtime.cc:284]
at Consumer.Mobile.Views.RedirectPage.OnBackButtonPressed () [0x00001] in ~\Views\RedirectPage.xaml.cs:66
at Xamarin.Forms.Page.SendBackButtonPressed () [0x00000] in <filename unknown>:0
at Xamarin.Forms.NavigationPage.OnBackButtonPressed () [0x00000] in <filename unknown>:0
at Xamarin.Forms.Page.SendBackButtonPressed () [0x00000] in <filename unknown>:0
at Xamarin.Forms.Platform.Android.Platform.HandleBackPressed (System.Object sender, System.EventArgs e) [0x00000] in <filename unknown>:
at Xamarin.Forms.Platform.Android.FormsApplicationActivity.OnBackPressed () [0x00000] in <filename unknown>:0
at XLabs.Forms.XFormsApplicationDroid.<>n__FabricatedMethod5 () [0x00000] in <filename unknown>:0
at XLabs.Forms.XFormsApplicationDroid+<OnBackPressed>d__0.MoveNext () [0x00000] in <filename unknown>:0
at void mono.java.lang.RunnableImplementor.n_run() (RunnableImplementor.java:-2)
at void mono.java.lang.RunnableImplementor.run() (RunnableImplementor.java:29)
at void android.os.Handler.handleCallback(android.os.Message) (Handler.java:739)