关于4.2的ActionBar高度

    <!-- Maximum height for a stacked tab bar as part of an action bar -->
    <dimen name="action_bar_stacked_max_height">48dp</dimen>


    <!-- Maximum width for a stacked action bar tab. This prevents
         action bar tabs from becoming too wide on a wide screen when only
         a few are present. -->
    <dimen name="action_bar_stacked_tab_max_width">180dp</dimen>

frameworks/base/core/res/values/Dimens.xml 48dp 把这个值改大就行了

http://www.eoeandroid.com/thread-264468-1-1.html