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Created attachment 14816 [details]
style.xml can't be used
<package id="Xamarin.Forms" version="18.104.22.16808-pre3" targetFramework="monoandroid60" />
Compile using Android version: Use Latest Platform (Android 6.0 Marshmallow)
Minimum Android to target; Android 4.0.3 (API Level 15)
Target Android version: Use Compile using SDK version
Compiling this on VS2015 / Win10
Xamarin 22.214.171.124 (413372c)
Xamarin.Android 126.96.36.199 (e98e962)
Application errors out on launch at LoadApplication(new App()); in MainActivity.cs with the following error:
01-31 07:07:08.315 I/MonoDroid(26231): UNHANDLED EXCEPTION:
01-31 07:07:08.315 I/MonoDroid(26231): System.NullReferenceException: Object reference not set to an instance of an object
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.Platform.UpdateActionBarHomeAsUp (Android.App.ActionBar actionBar) [0x0001d] in <filename unknown>:0
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.Platform.HideActionBar () [0x0000d] in <filename unknown>:0
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.Platform.UpdateActionBar () [0x000a0] in <filename unknown>:0
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.Platform.SetPage (Xamarin.Forms.Page newRoot) [0x000bd] in <filename unknown>:0
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.FormsApplicationActivity.InternalSetPage (Xamarin.Forms.Page page) [0x000b7] in <filename unknown>:0
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.FormsApplicationActivity.SetMainPage () [0x0000c] in <filename unknown>:0
01-31 07:07:08.315 I/MonoDroid(26231): at Xamarin.Forms.Platform.Android.FormsApplicationActivity.LoadApplication (Xamarin.Forms.Application application) [0x0002d] in <filename unknown>:0
01-31 07:07:08.325 I/MonoDroid(26231): at App23.Droid.MainActivity.OnCreate (Android.OS.Bundle bundle) [0x00020] in C:\Users\xyz\Documents\Visual Studio 2015\Projects\App23\App23\App23.Droid\MainActivity.cs:24
01-31 07:07:08.325 I/MonoDroid(26231): at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (IntPtr jnienv, IntPtr native__this, IntPtr native_savedInstanceState) [0x00011] in /Users/builder/data/lanes/2692/e98e9627/source/monodroid/src/Mono.Android/platforms/android-23/src/generated/Android.App.Activity.cs:2857
01-31 07:07:08.325 I/MonoDroid(26231): at (wrapper dynamic-method) System.Object:0d4ea3af-d627-4c79-af83-fd09d236a7f1 (intptr,intptr,intptr)
01-31 07:07:08.335 W/art (26231): JNI RegisterNativeMethods: attempt to register 0 native methods for md52ce486a14f4bcd95899665e9d932190b.JavaProxyThrowable
I noticed Xamarin.Android works fine, so this must be a Forms issue.
Please see repro.
Also created a thread: http://forums.xamarin.com/discussion/60091/updating-xamarin-to-the-latest-stable-seems-to-have-broken-android-custom-styles-for-xf#latest
This issue is happening on both Visual Studio and Xamarin Studio.
I rolled back to the following versions, however the issue still persists:
Based on the stack trace, I'm going to surmise that the exception happens because Activity.ActionBar is null.
Based on that assumption, observe $ANDROID_SDK_PATH/platforms/android-23/data/res/values/themes.xml:
<!-- ... -->
<!-- ... -->
<!-- Default theme with an Action Bar. -->
i.e. the default android:Theme resource does NOT support the ActionBar, and thus (I assume) Activity.ActionBar returns null.
If you need the action bar -- and presumably Xamarin.Forms requires the action bar -- then use a style which supports it:
<style name="MyTheme" parent="android:Theme.WithActionBar">
Please try that.
Jonathan, I do not need the action bar or the status bar. I want to go full screen. If, however, Xamarin Forms requires an ActionBar, then I can use another theme and hide it programmatically at startup. I'll try your suggestion later today and get back with you. I remember android:Theme working for me before I upgraded Xamarin. I just can't remember what version of Xamarin I was using before.
Theme.WithActionBar did not work for me. I think the problem is using any theme throws an error. Did you test run the repro I submitted? Did it work for you? Please suggest a reason as to why this bug's status was changed to "NEEDINFO".
Please suggest a reason as to why this bug's status was changed to "NEEDINFO". I'd like to understand if my repro is producible on your end.
I noticed the problem is with these two lines:
These are throwing the exception whether I set my theme to android:Theme or android:Theme.WithActionBar. They used to work before.
This could be closed as I figured out a way to hide the title bar properly. I believe I was approaching things from the wrong perspective.