我已经用PCL构建了一个Xamarin表单应用程序。
应用程序有时会在await Navigation.PopAsync();崩溃
我找到了这个https://forums.xamarin.com/discussion/62414/app-resuming-results-in-crash-with-formsappcompatactivity，但它没有帮助
它只出现在Android 5.0及更高版本上。我正在使用Xamarin.Forms 2.3.3
这是崩溃日志：
Xamarin caused by: android.runtime.JavaProxyThrowable: System.AggregateException: A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread. ---> System.AggregateException: One or more errors occurred. ---> Java.Lang.RuntimeException: Can not perform this action after onSaveInstanceState
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at Java.Interop.JniEnvironment+InstanceMethods.CallIntMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method) [0x00084] in <bd356ef77b9a4127a500b8385b303c4b>:0
at Android.Runtime.JNIEnv.CallIntMethod (System.IntPtr jobject, System.IntPtr jmethod) [0x0000e] in <bc38a7e9ac144e5b8f3cbfa1d1cb295b>:0
at Android.Support.V4.App.FragmentTransactionInvoker.Commit () [0x00033] in <27c17fe440cf491ba8255bcefade6e02>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.SwitchContentAsync (Xamarin.Forms.Page view, System.Boolean animated, System.Boolean removed, System.Boolean popToRoot) [0x0014b] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnPopViewAsync (Xamarin.Forms.Page page, System.Boolean animated) [0x00021] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.PopViewAsync (Xamarin.Forms.Page page, System.Boolean animated) [0x00000] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnPopped (System.Object sender, Xamarin.Forms.Internals.NavigationRequestedEventArgs e) [0x0000e] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.NavigationPage+<Xamarin-Forms-INavigationPageController-PopAsyncInner>d__63.MoveNext () [0x0006e] in <83d3340f3b274d389854ce45f51043f6>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () [0x00000] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at Xamarin.Forms.NavigationPage+<PopAsync>d__38.MoveNext () [0x001b9] in <83d3340f3b274d389854ce45f51043f6>:0
--- End of inner exception stack trace ---
at Xamarin.Forms.NavigationPage+<>c.<SafePop>b__93_0 (System.Threading.Tasks.Task`1[TResult] t) [0x0000e] in <83d3340f3b274d389854ce45f51043f6>:0
at System.Threading.Tasks.ContinuationTaskFromResultTask`1[TAntecedentResult].InnerInvoke () [0x00027] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Threading.Tasks.Task.Execute () [0x00016] in <7f637a73ebd0402caa24252e5f30bf7b>:0
--- End of inner exception stack trace ---
---> (Inner Exception #0) System.AggregateException: One or more errors occurred. ---> Java.Lang.RuntimeException: Can not perform this action after onSaveInstanceState
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at Java.Interop.JniEnvironment+InstanceMethods.CallIntMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method) [0x00084] in <bd356ef77b9a4127a500b8385b303c4b>:0
at Android.Runtime.JNIEnv.CallIntMethod (System.IntPtr jobject, System.IntPtr jmethod) [0x0000e] in <bc38a7e9ac144e5b8f3cbfa1d1cb295b>:0
at Android.Support.V4.App.FragmentTransactionInvoker.Commit () [0x00033] in <27c17fe440cf491ba8255bcefade6e02>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.SwitchContentAsync (Xamarin.Forms.Page view, System.Boolean animated, System.Boolean removed, System.Boolean popToRoot) [0x0014b] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnPopViewAsync (Xamarin.Forms.Page page, System.Boolean animated) [0x00021] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.PopViewAsync (Xamarin.Forms.Page page, System.Boolean animated) [0x00000] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnPopped (System.Object sender, Xamarin.Forms.Internals.NavigationRequestedEventArgs e) [0x0000e] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.NavigationPage+<Xamarin-Forms-INavigationPageController-PopAsyncInner>d__63.MoveNext () [0x0006e] in <83d3340f3b274d389854ce45f51043f6>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () [0x00000] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at Xamarin.Forms.NavigationPage+<PopAsync>d__38.MoveNext () [0x001b9] in <83d3340f3b274d389854ce45f51043f6>:0
--- End of inner exception stack trace ---
at Xamarin.Forms.NavigationPage+<>c.<SafePop>b__93_0 (System.Threading.Tasks.Task`1[TResult] t) [0x0000e] in <83d3340f3b274d389854ce45f51043f6>:0
at System.Threading.Tasks.ContinuationTaskFromResultTask`1[TAntecedentResult].InnerInvoke () [0x00027] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Threading.Tasks.Task.Execute () [0x00016] in <7f637a73ebd0402caa24252e5f30bf7b>:0
---> (Inner Exception #0) Java.Lang.RuntimeException: Can not perform this action after onSaveInstanceState
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at Java.Interop.JniEnvironment+InstanceMethods.CallIntMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method) [0x00084] in <bd356ef77b9a4127a500b8385b303c4b>:0
at Android.Runtime.JNIEnv.CallIntMethod (System.IntPtr jobject, System.IntPtr jmethod) [0x0000e] in <bc38a7e9ac144e5b8f3cbfa1d1cb295b>:0
at Android.Support.V4.App.FragmentTransactionInvoker.Commit () [0x00033] in <27c17fe440cf491ba8255bcefade6e02>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.SwitchContentAsync (Xamarin.Forms.Page view, System.Boolean animated, System.Boolean removed, System.Boolean popToRoot) [0x0014b] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnPopViewAsync (Xamarin.Forms.Page page, System.Boolean animated) [0x00021] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.PopViewAsync (Xamarin.Forms.Page page, System.Boolean animated) [0x00000] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnPopped (System.Object sender, Xamarin.Forms.Internals.NavigationRequestedEventArgs e) [0x0000e] in <651b788f2205433c9db3a98957b5b8aa>:0
at Xamarin.Forms.NavigationPage+<Xamarin-Forms-INavigationPageController-PopAsyncInner>d__63.MoveNext () [0x0006e] in <83d3340f3b274d389854ce45f51043f6>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0004e] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () [0x00000] in <7f637a73ebd0402caa24252e5f30bf7b>:0
at Xamarin.Forms.NavigationPage+<PopAsync>d__38.MoveNext () [0x001b9] in <83d3340f3b274d389854ce45f51043f6>:0
--- End of managed Java.Lang.RuntimeException stack trace ---
java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState
at android.support.v4.app.FragmentManagerImpl.checkStateLoss(FragmentManager.java:1493)
at android.support.v4.app.FragmentManagerImpl.enqueueAction(FragmentManager.java:1511)
at android.support.v4.app.BackStackRecord.commitInternal(BackStackRecord.java:638)
at android.support.v4.app.BackStackRecord.commit(BackStackRecord.java:617)
at md5b60ffeb829f638581ab2bb9b1a7f4f3f.FormsAppCompatActivity.n_onBackPressed(Native Method)
at md5b60ffeb829f638581ab2bb9b1a7f4f3f.FormsAppCompatActivity.onBackPressed(FormsAppCompatActivity.java:40)
at android.app.Activity.onKeyUp(Activity.java:2713)
at android.view.KeyEvent.dispatch(KeyEvent.java:3280)
at android.app.Activity.dispatchKeyEvent(Activity.java:2983)
at android.support.v7.app.AppCompatActivity.dispatchKeyEvent(AppCompatActivity.java:524)
at android.support.v7.view.WindowCallbackWrapper.dispatchKeyEvent(WindowCallbackWrapper.java:50)
at android.support.v7.app.AppCompatDelegateImplBase$AppCompatWindowCallbackBase.dispatchKeyEvent(AppCompatDelegateImplBase.java:241)
at android.support.v7.view.WindowCallbackWrapper.dispatchKeyEvent(WindowCallbackWrapper.java:50)
at com.android.internal.policy.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:2689)
at android.view.ViewRootImpl$ViewPostImeInputStage.processKeyEvent(ViewRootImpl.java:5233)
at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:5186)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4633)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4686)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4652)
at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:4794)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:4660)
at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:4851)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4633)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4686)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4652)
at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:4660)
at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4633)
at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4686)
at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4652)
at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:4827)
at android.view.ViewRootImpl$ImeInputStage.onFinishedInputEvent(ViewRootImpl.java:5070)
at android.view.inputmethod.InputMethodManager$PendingEvent.run(InputMethodManager.java:2877)
at android.view.inputmethod.InputMethodManager.invokeFinishedInputEventCallback(InputMethodManager.java:2449)
at android.view.inputmethod.InputMethodManager.finishedInputEvent(InputMethodManager.java:2440)
at android.view.inputmethod.InputMethodManager$ImeInputEventSender.onInputEventFinished(InputMethodManager.java:2854)
at android.view.InputEventSender.dispatchInputEventFinished(InputEventSender.java:141)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:323)
at android.os.Looper.loop(Looper.java:143)
at android.app.ActivityThread.main(ActivityThread.java:7230)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
答案 0 :(得分：2)
因为 FormsAppCompatActivity
没有允许你的代码操纵页面diplaying ...
这就是全部。我搜索了很多，而且这一刻别无选择。也许这是一个错误，无论如何我们都有推送的权利，所以就是这样。但它不会。 我选择的解决方案是：
答案 1 :(得分：0)
第一行是说您的任务崩溃，因此您的应用程序崩溃了。添加此类
public static class LogException
{
public static void LogExceptions(this Task task)
{
task.ContinueWith(t =>
{
var aggException = t.Exception.Flatten();
foreach (var exception in aggException.InnerExceptions)
{
System.Diagnostics.Debug.WriteLine("LOG EXCEPTION catch: " + exception);
}
},
TaskContinuationOptions.OnlyOnFaulted);
}
}
并像这样使用它：
Task.Factory.StartNew(() => PopYourPage()).LogExceptions();
会抓住这些例外而不是杀死你的应用。 你弹出什么，能否更好地解释一下？