title: System.TypeLoadException Could not load type CategoryActivity
body: <p>I have written an Activity class with following definition</p>
  
  <pre><code>[Activity(Label = "Courses", MainLauncher = true, Icon = "@drawable/icon")]
  public class CategoryActivity : ListActivity
  {
      CourseCategoryManager _courseCategoryManager;
  
      protected override void OnCreate(Bundle savedInstanceState)
      {
          base.OnCreate(savedInstanceState);
  
          _courseCategoryManager = new CourseCategoryManager();
          ListAdapter = new CourseCategoryManagerAdapter(this,
              global::Android.Resource.Layout.SimpleListItem1,
              _courseCategoryManager);
      }
  
   }
  </code></pre>
  
  <p>The purpose of this activity class is to display all categories as List Items.</p>
  
  <p>But when I run the application it returns me following exception:</p>
  
  <pre><code>01-23 14:27:19.157 E/MonoDroid( 2137): Could not load type 'Courses.Android.CategoriesActivity, Courses.Android, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. Skipping JNI registration of type 'md5ba6caf9a9061d0cbb25c0daaef535be4/CategoriesActivity'.
  An unhandled exception occured.
  
  01-23 14:27:20.371 I/art     ( 2137): Thread[2,tid=2143,WaitingInMainSignalCatcherLoop,Thread*=0xaf478400,peer=0x12c00080,"Signal Catcher"]: reacting to signal 3
  01-23 14:27:21.224 I/art     ( 2137): Wrote stack traces to '/data/anr/traces.txt'
  01-23 14:27:23.305 I/MonoDroid( 2137): UNHANDLED EXCEPTION:
  01-23 14:27:23.526 I/MonoDroid( 2137): System.TypeLoadException: Could not load type 'Courses.Android.CategoriesActivity, Courses.Android, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' from assembly ''.
  01-23 14:27:23.526 I/MonoDroid( 2137):   at (wrapper managed-to-native) System.Type:internal_from_name (string,bool,bool)
  01-23 14:27:23.527 I/MonoDroid( 2137):   at System.Type.GetType (System.String typeName, Boolean throwOnError) [0x00011] in /Users/builder/data/lanes/2098/3efa14c4/source/mono/mcs/class/corlib/ReferenceSources/Type.cs:57 
  01-23 14:27:23.527 I/MonoDroid( 2137):   at Java.Interop.TypeManager.n_Activate (IntPtr jnienv, IntPtr jclass, IntPtr typename_ptr, IntPtr signature_ptr, IntPtr jobject, IntPtr parameters_ptr) [0x0007b] in /Users/builder/data/lanes/2098/3efa14c4/source/monodroid/src/Mono.Android/src/Java.Interop/TypeManager.cs:145 
  01-23 14:27:23.527 I/MonoDroid( 2137):   at (wrapper dynamic-method) System.Object:90d2a13e-584b-4a05-a439-c9d6ba401669 (intptr,intptr,intptr,intptr,intptr,intptr)
  01-23 14:27:23.644 W/art     ( 2137): JNI RegisterNativeMethods: attempt to register 0 native methods for md52ce486a14f4bcd95899665e9d932190b.JavaProxyThrowable
  An unhandled exception occured.
  
  01-23 14:27:24.452 E/mono    ( 2137): 
  01-23 14:27:24.452 E/mono    ( 2137): Unhandled Exception:
  01-23 14:27:24.452 E/mono    ( 2137): System.TypeLoadException: Could not load type 'Courses.Android.CategoriesActivity, Courses.Android, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' from assembly ''.
  01-23 14:27:24.452 E/mono    ( 2137):   at (wrapper dynamic-method) System.Object:90d2a13e-584b-4a05-a439-c9d6ba401669 (intptr,intptr,intptr,intptr,intptr,intptr)
  01-23 14:27:24.452 E/mono    ( 2137):   at (wrapper native-to-managed) System.Object:90d2a13e-584b-4a05-a439-c9d6ba401669 (intptr,intptr,intptr,intptr,intptr,intptr)
  01-23 14:27:24.453 E/mono-rt ( 2137): [ERROR] FATAL UNHANDLED EXCEPTION: System.TypeLoadException: Could not load type 'Courses.Android.CategoriesActivity, Courses.Android, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' from assembly ''.
  01-23 14:27:24.453 E/mono-rt ( 2137):   at (wrapper dynamic-method) System.Object:90d2a13e-584b-4a05-a439-c9d6ba401669 (intptr,intptr,intptr,intptr,intptr,intptr)
  01-23 14:27:24.453 E/mono-rt ( 2137):   at (wrapper native-to-managed) System.Object:90d2a13e-584b-4a05-a439-c9d6ba401669 (intptr,intptr,intptr,intptr,intptr,intptr)
  referenceTable GDEF length=670 1
  referenceTable GSUB length=7202 1
  referenceTable GPOS length=24560 1
  </code></pre>