Vertical line separating master and detail doesn't show


#1

In the book in Figure 22.6 there is a vertical line separating master and detail views on a tablet. When I run the app up to that point there is no vertical line separation and the two fragments appear to have no clear separation.


#2

I used this to make a divider show up…

...
    android:showDividers="middle"
    android:divider="?android:attr/listDivider"
...