About Android support design library

<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/root_view"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:fitsSystemWindows="true">

        <android.support.design.widget.CollappingToolbarLayout
            android: id="@+id/collapsing_toolbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:contentScrim="@color/primary_color"
            app:layout_scrollFlags="scroll | exitUntilCollapsed">
            <TextView
                android: id="@+id/ex_text"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                app:layout_collapseMode="parallax"
                android:background="@color/accent_color"
                android: text="@string/kawiais_ex_text"
                android:textSize="16sp"
                android:gravity="center"
                android:paddingLeft="24dp"
                android:paddingRight="24dp"
                android:textColor="@android:color/white"/>
            <android.support.v7.widget.Toolbar
                android: id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:theme="@style/ThemeOverlay.AppCompat.ActionBar"
                app:layout_scrollFlags="scroll|enterAllways"
                app: title="@string/title_kaiwai_list"
                app:layout_collapseMode="pin"/>
        </android.support.design.widget.CollappingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"/>



    <android.support.design.widget.FloatingActionButton
        android: id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="16dp"
        android: src="@drawable/ic_add_white"
        app:fabSize="normal"
        app: borderWidth="0dp"
        app:backgroundTint="@color/fab_color"/>

    <com.rey.material.widget.ProgressView
        android: id="@+id/progress"
        android:layout_width="@dimen/progress_size"
        android:layout_height="@dimen/progress_size"
        app:pv_progressMode="indeterminate"
        app:pv_progressStyle="@style/progress_style"
        app:pv_autostart="true"
        app: pv_circular="true"
        android:layout_gravity="center"/>

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