在带有使用BottomNavigationView和Fragment实现的标签的屏幕上工作，这些标签又使用导航组件进行设置。我有3个标签，分别对应3个片段，中间的片段是一个recyclerview，其中包含一个简单的项目列表。当用户在中间片段中的列表中滚动时，我希望关闭屏幕工具栏和底部导航视图。为此，我对布局进行了以下更改，即主机活动主xml（这是工具栏所在的位置）
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<include
layout="@layout/action_bar_layout"/>
</android.support.design.widget.AppBarLayout>
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.BottomNavigationView
android:id="@+id/nav_view"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="0dp"
android:layout_marginEnd="0dp"
android:background="?android:attr/windowBackground"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:menu="@menu/bottom_nav_menu"
app:layout_behavior="@string/hide_bottom_view_on_scroll_behavior" />
<fragment
android:id="@+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
app:defaultNavHost="true"
android:layout_marginTop="?actionBarSize"
app:layout_constraintBottom_toTopOf="@id/nav_view"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="@navigation/mobile_navigation"/>
</android.support.constraint.ConstraintLayout>
</android.support.design.widget.CoordinatorLayout>
我已按照此处的建议将滚动标志添加到工具栏
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/my_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
android:elevation="4dp"
android:fitsSystemWindows="true"
android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
app:layout_scrollFlags="scroll|enterAlways">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:id="@+id/action_back_container"
android:layout_width="48dp"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:background="@android:color/transparent">
<ImageView
android:id="@+id/action_back"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:background="@android:color/transparent" />
</RelativeLayout>
<TextView
android:id="@+id/toolbar_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@android:color/white"
style="@style/TextAppearance.AppCompat.Widget.ActionBar.Title"
android:layout_centerInParent="true"/>
<View
android:id="@+id/navBarLine"
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_alignParentBottom="true" />
</RelativeLayout>
</android.support.v7.widget.Toolbar>
这是包含列表的片段的xml，我已将app:layout_behavior字段添加到recyclerview以激活滚动
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
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:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/white">
<TextView
android:id="@+id/text_dashboard"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:textAlignment="center"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<include
android:id="@+id/content"
layout="@layout/content_service_provider_list"
tools:layout_editor_absoluteX="0dp"
tools:layout_editor_absoluteY="0dp" />
<android.support.design.widget.FloatingActionButton
android:id="@+id/floating_button_snackbar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="16dp"
android:src="@drawable/ic_add"
app:fabSize="normal"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
android:visibility="gone"/>
</android.support.constraint.ConstraintLayout>
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.FpxMainActivity"
tools:showIn="@layout/fragment_connections">
<android.support.v4.widget.SwipeRefreshLayout
android:id="@+id/swipe_container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="@+id/sp_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"/>
</android.support.v4.widget.SwipeRefreshLayout>
</android.support.constraint.ConstraintLayout>
即使进行了所有这些更改，工具栏和底部导航视图也不会消失，我是否应该更改某些内容？