gistfile1.java

ViewPager viewPager = (ViewPager) this.findViewById(R.id.view_pager);
Resources resources = this.getResources();
int viewPagerPageMargin = resources.getDimensionPixelSize(R.dimen.view_pager_page_margin);
viewPager.setPageMargin(viewPagerPageMargin);
viewPager.setPageMarginDrawable(R.drawable.shape_view_pager_divider);

gistfile2.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle" >

    <solid android:color="@android:color/black" />

</shape>

gistfile3.xml

<resources>

    <!-- Default screen margins, per the Android Design guidelines. -->
    <dimen name="activity_horizontal_margin">16dp</dimen>
    <dimen name="activity_vertical_margin">16dp</dimen>
    <dimen name="view_pager_page_margin">4dp</dimen>

</resources>