07-09 07:28:38.350: E/AndroidRuntime(1437): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.googleplay.ui.activity.MainActivity" on path: DexPathList[[zip file "/data/app/com.example.googleplay-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.example.googleplay-2, /system/lib]]

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context=".MainActivity" >

    <com.example.googleplay.view.PagerTab

        android:id="@+id/pt_pagertab"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content" />

    <android.support.v4.view.ViewPager

        android:id="@+id/vp_viewpager"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content" />

</RelativeLayout>