CollapsingToolbar不会崩溃

Question

我对android很新，并且在滚动期间尝试隐藏工具栏，并希望在滚动面相反时显示它。我按照我发现互联网的说明，但代码中缺少一些东西，不允许我实现这一点。下面显示的代码是我的活动布局，第二部分是活动内部的片段。虽然一切看起来都井井有条但我无法做到这一点。

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
                                xmlns:app="http://schemas.android.com/apk/res-auto"
                                android:id="@+id/drawer_layout"
                                android:layout_width="match_parent"
                                android:layout_height="match_parent">

    <android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
                                             xmlns:tools="http://schemas.android.com/tools"
                                             android:id="@+id/coordinatorLayout"
                                             android:layout_width="match_parent"
                                             android:layout_height="match_parent"
                                             tools:context=".view.HomeActivity">    <!-- The ActionBar displayed at the top -->
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">
        <android.support.design.widget.AppBarLayout
                android:layout_width="match_parent"
                android:layout_height="55dp"
                android:fitsSystemWindows="true"
                android:theme="@style/SkorAdamThemeTeam.ActionBarTheme">
            <android.support.design.widget.CollapsingToolbarLayout
                    android:id="@+id/mainCollapsing"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    app:titleEnabled="false"
                    app:scrimAnimationDuration="0"
                    app:statusBarScrim="@android:color/transparent"
                    app:contentScrim="@android:color/transparent"
                    android:fitsSystemWindows="true"
                    app:paddingStart="0dp"
                    app:paddingEnd="0dp"
                    android:layout_gravity="top"
                    app:layout_scrollFlags="scroll|exitUntilCollapsed">

                <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/toolbar"
                        android:layout_height="wrap_content"
                        android:layout_width="match_parent"
                        android:fitsSystemWindows="true"
                        app:layout_collapseMode="parallax"
                        app:theme="@style/SkorAdamTheme.ActionBarTheme"
                        android:background="?attr/colorAccent">
                </android.support.v7.widget.Toolbar>
            </android.support.design.widget.CollapsingToolbarLayout>
        </android.support.design.widget.AppBarLayout>
        <android.support.design.widget.CoordinatorLayout
                android:id="@+id/container_body"
                android:layout_width="match_parent"
                app:layout_behavior="@string/appbar_scrolling_view_behavior"
                android:layout_height="0dp"
                android:layout_weight="1" />

        <LinearLayout
                android:id="@+id/container_toolbar_bottom"
                android:layout_width="match_parent"
                android:layout_height="wrap_content">

            <include
                    android:id="@+id/toolbar_bottom"
                    layout="@layout/toolbar_bottom" />
        </LinearLayout>
        <ProgressBar
                android:id="@+id/progressBar"
                style="?android:attr/progressBarStyle"
                android:layout_gravity="center"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:layout_centerHorizontal="true"
                android:layout_centerVertical="true" />
        </LinearLayout>
    </android.support.design.widget.CoordinatorLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view_search"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="end"
        android:background="#F6F6F6"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/search_layout"
        app:menu="@menu/menu_search">

    </android.support.design.widget.NavigationView>

    <!-- The navigation drawer that comes from the left -->
    <!-- Note that `android:layout_gravity` needs to be set to 'start' -->
    <android.support.design.widget.NavigationView
        android:id="@+id/nvView"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:background="@color/colorPrimaryBlack"
        app:itemTextColor="@color/light_grey"
        app:itemBackground="@drawable/menu_divider"
        app:menu="@menu/drawer_view"
        app:headerLayout="@layout/navigation_drawer_header">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:layout_marginTop="-8dp"
        android:clickable="true"
        android:orientation="horizontal" />

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

<!-----------fragment------------->

<android.support.v7.widget.RecyclerView
    android:background="#e0e7e8"
    android:id="@+id/today_recyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:nestedScrollingEnabled="false"
    android:animateLayoutChanges="false"        appbar_scrolling_view_behavior="@string/appbar_scrolling_view_behavior"
    xmlns:android="http://schemas.android.com/apk/res/android"/>