EROR WHEN PROJECT WORKING #16

hi all EROR STRING :

01-08 09:46:01.033: E/AndroidRuntime(12473): FATAL EXCEPTION: main
01-08 09:46:01.033: E/AndroidRuntime(12473): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.jake.quiltview/com.jake.quiltview.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.jake.quiltview.MainActivity" on path: DexPathList[[zip file "/data/app/com.jake.quiltview-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.jake.quiltview-2, /vendor/lib, /system/lib]]
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2232)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2358)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.ActivityThread.access$600(ActivityThread.java:156)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1340)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.os.Handler.dispatchMessage(Handler.java:99)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.os.Looper.loop(Looper.java:153)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.ActivityThread.main(ActivityThread.java:5299)
01-08 09:46:01.033: E/AndroidRuntime(12473): at java.lang.reflect.Method.invokeNative(Native Method)
01-08 09:46:01.033: E/AndroidRuntime(12473): at java.lang.reflect.Method.invoke(Method.java:511)
01-08 09:46:01.033: E/AndroidRuntime(12473): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833)
01-08 09:46:01.033: E/AndroidRuntime(12473): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
01-08 09:46:01.033: E/AndroidRuntime(12473): at dalvik.system.NativeStart.main(Native Method)
01-08 09:46:01.033: E/AndroidRuntime(12473): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.jake.quiltview.MainActivity" on path: DexPathList[[zip file "/data/app/com.jake.quiltview-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.jake.quiltview-2, /vendor/lib, /system/lib]]
01-08 09:46:01.033: E/AndroidRuntime(12473): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
01-08 09:46:01.033: E/AndroidRuntime(12473): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
01-08 09:46:01.033: E/AndroidRuntime(12473): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.Instrumentation.newActivity(Instrumentation.java:1054)
01-08 09:46:01.033: E/AndroidRuntime(12473): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2223)
01-08 09:46:01.033: E/AndroidRuntime(12473): ... 11 more