导航抽屉列表中的下划线菜单项

Question

如何在导航抽屉中下划线菜单项？

期望:

现实:

@菜单/ activity_navigation_drawer:

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

<group android:checkableBehavior="single">
    <item
        android:id="@+id/nav_open_account"
        android:title="@string/na_navigate_open_account" />
    <item
        android:id="@+id/nav_login"
        android:title="@string/na_navigate_login" />
    <item
        android:id="@+id/nav_stock_signals"
        android:title="@string/na_navigate_stock_signals" />

    ...

</group>

导航抽屉活动布局:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout     xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="end">

<include
    layout="@layout/app_bar_navigation"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<android.support.design.widget.NavigationView
    android:id="@+id/nav_view"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_gravity="end"
    android:fitsSystemWindows="true"
    android:background="@color/primary_asphalt_dark"
    app:headerLayout="@layout/nav_header_navigation"
    app:menu="@menu/activity_navigation_drawer" /> 

</android.support.v4.widget.DrawerLayout>

告诉我是否需要更多代码.

Answer 1

每个组以行分隔符结束.因此,如果菜单中的每个项目都有自己的组,您将获得所需的图形输出:

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

    <group android:id="@+id/nav_open_account_group"
        android:checkableBehavior="single">
        <item
            android:id="@+id/nav_open_account"
            android:title="@string/na_navigate_open_account" />
        </group>
    <group android:id="@+id/nav_login_group"
        android:checkableBehavior="single">
        <item
            android:id="@+id/nav_login"
            android:title="@string/na_navigate_login" />
    </group>
    <group android:id="@+id/nav_stock_signals_group"
        android:checkableBehavior="single">
        <item
            android:id="@+id/nav_stock_signals"
            android:title="@string/na_navigate_stock_signals" />
     </group>

        ...

    </menu>

请注意,每个组的不同ID都是必需的.