I have an app that uses the v4 and v7 support libraries. It runs absolutely fine in debug, but now i've gone to run it in Release mode im getting an error relating to the Theme.
"You need to use a Theme.AppCompat theme (or descendant) with this activity."
This is the declaration at the top of my app, where i DO declare an AppCompat theme:
[Activity(Label = "My App", LaunchMode = LaunchMode.SingleTask, Theme="@style/Theme.AppCompat.Light", ScreenOrientation = ScreenOrientation.Portrait)]
I also declare it in the Manifest:
<application android:icon="@drawable/logo" android:debuggable="false" android:label="My App" android:theme="@style/Theme.AppCompat.Light">
Here is my stack trace. Any help would be very much appreciated.
libc] WARNING: generic atexit() called from legacy shared library
[monodroid-gc] GREF GC Threshold: 46800
[dalvikvm-heap] Grow heap (frag case) to 9.750MB for 803952-byte allocation
[dalvikvm-heap] Grow heap (frag case) to 11.473MB for 1607840-byte allocation
[Adreno-EGL] <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
[OpenGLRenderer] Enabling debug mode 0
[Request] Warning: Sessionless Request needs token but missing either application ID or client token.
[MonoDroid] UNHANDLED EXCEPTION:
[MonoDroid] Java.Lang.RuntimeException: Exception of type 'Java.Lang.RuntimeException' was thrown.
[MonoDroid] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x00028>
[MonoDroid] at Android.Runtime.JNIEnv.CallNonvirtualVoidMethod (intptr,intptr,intptr,Android.Runtime.JValue[]) <0x000e7>
[MonoDroid] at Android.App.Activity.OnCreate (Android.OS.Bundle) <0x001f3>
[MonoDroid] at FrogPoint.Droid.MainActivity.OnCreate (Android.OS.Bundle) <0x0001f>
[MonoDroid] at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (intptr,intptr,intptr) <0x0005b>
[MonoDroid] at (wrapper dynamic-method) object.167c14b1-1233-456f-ab3e-1b59de9fa9bf (intptr,intptr,intptr) <0x00043>
[MonoDroid] --- End of managed exception stack trace ---
[MonoDroid] java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
[MonoDroid] at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:110)
[MonoDroid] at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:57)
[MonoDroid] at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:99)
[MonoDroid] at frogpoint.droid.MainActivity.n_onCreate(Native Method)
[MonoDroid] at frogpoint.droid.MainActivity.onCreate(MainActivity.java:41)
[MonoDroid] at android.app.Activity.performCreate(Activity.java:5231)
[MonoDroid] at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
[MonoDroid] at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
[MonoDroid] at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
[MonoDroid] at android.app.ActivityThread.access$800(ActivityThread.java:135)
[MonoDroid] at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
[MonoDroid] at android.os.Handler.dispatchMessage(Handler.java:102)
[MonoDroid] at android.os.Looper.loop(Looper.java:136)
[MonoDroid] at android.app.ActivityThread.main(ActivityThread.java:5001)
[MonoDroid] at java.lang.reflect.Method.invokeNative(Native Method)
[MonoDroid] at java.lang.reflect.Method.invoke(Method.java:515)
[MonoDroid] at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
[MonoDroid] at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
[MonoDroid] at dalvik.system.NativeStart.main(Native Method)
[mono]
[mono] Unhandled Exception:
[mono] Java.Lang.RuntimeException: Exception of type 'Java.Lang.RuntimeException' was thrown.
[mono] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x00028>
[mono] at Android.Runtime.JNIEnv.CallNonvirtualVoidMethod (intptr,intptr,intptr,Android.Runtime.JValue[]) <0x000e7>
[mono] at Android.App.Activity.OnCreate (Android.OS.Bundle) <0x001f3>
[mono] at FrogPoint.Droid.MainActivity.OnCreate (Android.OS.Bundle) <0x0001f>
[mono] at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (intptr,intptr,intptr) <0x0005b>
[mono] at (wrapper dynamic-method) object.167c14b1-1233-456f-ab3e-1b59de9fa9bf (intptr,intptr,intptr) <0x00043>
[mono]
[mono] --- End of managed exception stack trace ---
[mono] java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
[mono] at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:110)
[mono] at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:57)
[mono] at android.support.v7.app.ActionBarActivit
[mono-rt] [ERROR] FATAL UNHANDLED EXCEPTION: Java.Lang.RuntimeException: Exception of type 'Java.Lang.RuntimeException' was thrown.
[mono-rt] at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <0x00028>
[mono-rt] at Android.Runtime.JNIEnv.CallNonvirtualVoidMethod (intptr,intptr,intptr,Android.Runtime.JValue[]) <0x000e7>
[mono-rt] at Android.App.Activity.OnCreate (Android.OS.Bundle) <0x001f3>
[mono-rt] at FrogPoint.Droid.MainActivity.OnCreate (Android.OS.Bundle) <0x0001f>
[mono-rt] at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (intptr,intptr,intptr) <0x0005b>
[mono-rt] at (wrapper dynamic-method) object.167c14b1-1233-456f-ab3e-1b59de9fa9bf (intptr,intptr,intptr) <0x00043>
[mono-rt]
[mono-rt] --- End of managed exception stack trace ---
[mono-rt] java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
[mono-rt] at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:110)
[mono-rt] at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:57)
[mono-rt] at android.support.v7.app.Act
So as we discussed in the comments to the OP. There is no need to use Support v7 if you are targeting Android 4.3 and up. Support packages are meant to give backwards compatibility to API levels which do not support the stuff from in newer API levels. Such as the ActionBar, Fragments etc. However since API 13, Fragments and ActionBar are included, so Support v7 is only needed for API levels below.
As for the crash you were experiencing, this was fixed in an earlier version of Xamarin.Android, so if you are not using any of the newer versions, this might have been the problem. Latest stable should be fine.