xamarin.android - NullReferenceException when calling ShowDialog on Android 2 -


i nullreferenceexception when calling acitiviy.showdialog(int) in response user tapping button. exception occurs in android 2.1 not in android 4.2. here stacktrace:

unhandled exception: system.nullreferenceexception: object reference not set instance of object @ (wrapper delegate-invoke) <module>.invoke_void__this___intptr_intptr_intptr_jvalue[] (intptr,intptr,intptr,android.runtime.jvalue[]) <0x000b3> @ android.runtime.jnienv.callvoidmethod (intptr,intptr,android.runtime.jvalue[]) <0x00053> @ android.app.activity.showdialog (int) <0x0011f> @ myapp.androidapp.invoiceactivity.showscheduledatedialog (object,system.eventargs) <0x0003b> @ android.views.view/ionclicklistenerimplementor.onclick (android.views.view) <0x00057> @ android.views.view/ionclicklistenerinvoker.n_onclick_landroid_view_view_ (intptr,intptr,intptr) <0x00063> @ (wrapper dynamic-method) object.be0dcca3-9ca4-47b4-a6a4-f691d34675f1 (intptr,intptr,intptr) <0x00043>

any ideas?

i found weird workaround. noticed if app opens alertdialog @ point before trying show datepickerdialog, works. doing this:

var helperdialog = new alertdialog.builder(this).settitle("").show(); helperdialog.hide();

right before returning datepickerdialog in oncreatedialog seems fix problem. it's ugly workaround, doesn't seem have side effects final user.

no idea if android bug or monodroid bug.


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