CalendarView horizontal lines disappear

Question

I created an activity with a CalendarView. When scrolling up and down, sometimes one of the grey horizontal lines disappears. See the following image for the lines I am talking about. What causes this?

view_calendar.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >
    <CalendarView
        android:id="@+id/calendar"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</RelativeLayout>

ViewCalendar.java

public class ViewCalendar extends Activity {

    @Override
    public void onCreate (Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.view_calendar); 
    }
}

Answer 1

In your "calender" one of the disappeared grey line shows that you are in that row. In that disappeared line one block shows grey pointing to the current date. Like in your "calender" that block 22. You can see in the image provided in the below link.

http://www.edumobile.org/android/android-development/calenderview-example/

Try this code in your xml-

<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" >
<CalendarView
    android:id="@+id/calendar"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
</RelativeLayout>