设置右上角的菜单button

效果如图：

刚開始是单独做了个button。发现无法调margin，后来想到外面套一个布局

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:paddingRight="8dp" >

<Button
    android:layout_gravity="center_vertical"
    android:id="@+id/widget_bt_done"
    android:text="@string/done"
     style="@style/Rounded_DarkBlue_FiveDegree_MenuButton"/>
</LinearLayout>

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

    <item
        android:id="@+id/menu_edit_done"
        android:title="@string/done"
        android:actionLayout="@layout/widget_done_button"
        android:showAsAction="always"
        />
</menu>

<style name="Rounded_DarkBlue_FiveDegree_MenuButton">
        <item name="android:background">@drawable/rounded_corner_button_dark_blue_five_degree</item>
        <item name="android:layout_height">33dp</item>
        <item name="android:layout_width">wrap_content</item>
        <item name="android:textColor">@color/defaultWhite</item>
    </style>