<android.support.design.widget.CoordinatorLayout
    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:fitsSystemWindows="true"
    tools:context="com.example.user.myapplication.ScrollingActivity">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/app_bar_height"
        android:fitsSystemWindows="true"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/toolbar_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            app:contentScrim="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/AppTheme.PopupOverlay"/>

        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

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

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_anchor="@id/app_bar"
        app:layout_anchorGravity="bottom|end">

        <Button
            android:id="@+id/disableNestedScrollingButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="disable"/>

        <Button
            android:id="@+id/enableNestedScrollingButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="enable"
            />
    </LinearLayout>

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

public class ScrollingActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_scrolling);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        final RecyclerView nestedView = (RecyclerView) findViewById(R.id.nestedView);
        findViewById(R.id.disableNestedScrollingButton).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(final View v) {
                nestedView.setNestedScrollingEnabled(false);
            }
        });
        findViewById(R.id.enableNestedScrollingButton).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(final View v) {
                nestedView.setNestedScrollingEnabled(true);
            }
        });
        nestedView.setLayoutManager(new LinearLayoutManager(this));
        nestedView.setAdapter(new Adapter() {
            @Override
            public ViewHolder onCreateViewHolder(final ViewGroup parent, final int viewType) {
                return new ViewHolder(LayoutInflater.from(parent.getContext()).inflate(
                        android.R.layout.simple_list_item_1,
                        parent,
                        false)) {
                };
            }

            @Override
            public void onBindViewHolder(final ViewHolder holder, final int position) {
                ((TextView) holder.itemView.findViewById(android.R.id.text1)).setText("item " + position);
            }

            @Override
            public int getItemCount() {
                return 100;
            }
        });
    }

}

<android.support.design.widget.CoordinatorLayout
    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:fitsSystemWindows="true"
    tools:context="com.example.user.myapplication.ScrollingActivity">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/app_bar_height"
        android:fitsSystemWindows="true"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/toolbar_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            app:contentScrim="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/AppTheme.PopupOverlay"/>

        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_gravity="fill_vertical"
        android:fillViewport="true"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">

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

        </RelativeLayout>

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

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_anchor="@id/app_bar"
        app:layout_anchorGravity="bottom|end">

        <Button
            android:id="@+id/disableNestedScrollingButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="disable"/>

        <Button
            android:id="@+id/enableNestedScrollingButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="enable"
            />
    </LinearLayout>

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

<android.support.design.widget.CoordinatorLayout
    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:fitsSystemWindows="true"
    tools:context="com.example.user.myapplication.ScrollingActivity">

    <android.support.design.widget.AppBarLayout
         android:id="@+id/app_bar"
         android:layout_width="match_parent"
         android:layout_height="@dimen/app_bar_height"
         android:fitsSystemWindows="true"
         android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:layout_scrollFlags="scroll|enterAlways"
            app:popupTheme="@style/AppTheme.PopupOverlay"
            app:title="Title" />

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

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

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_anchor="@id/app_bar"
        app:layout_anchorGravity="bottom|end">

        <Button
            android:id="@+id/disableNestedScrollingButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="disable"/>

        <Button
            android:id="@+id/enableNestedScrollingButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="enable"
            />
    </LinearLayout>
</android.support.design.widget.CoordinatorLayout>

// To disable collapsing
AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) toolbar.getLayoutParams();
params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_SNAP);
toolbar.setLayoutParams(params);

// To enable collapsing
AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) toolbar.getLayoutParams();
params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL|AppBarLayout.LayoutParams.SCROLL_FLAG_ENTER_ALWAYS);
toolbar.setLayoutParams(params);

android:nestedScrollingEnabled="false"

app:behavior_overlapTop = "24dp"

<android.support.design.widget.CoordinatorLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/background"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/app_bar_height"
        android:fitsSystemWindows="true"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/toolbar_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            app:contentScrim="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|exitUntilCollapsed">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/AppTheme.PopupOverlay"
                app:title="Title" />

        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>


    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginLeft="10dp"
        android:layout_marginRight="10dp"
        android:background="@android:color/transparent"
        app:behavior_overlapTop="@dimen/behavior_overlap_top"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <LinearLayout
            android:id="@+id/linearLayout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <android.support.v7.widget.RecyclerView
                android:id="@+id/recycler_view
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_margin="@dimen/text_min_padding"
                android:nestedScrollingEnabled="false"
                android:scrollbarSize="2dp"
                android:scrollbarStyle="outsideInset"
                android:scrollbarThumbVertical="@color/colorAccent"
                android:scrollbars="vertical" />

        </LinearLayout>

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

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

lockAppBarClosed();
ViewCompat.setNestedScrollingEnabled(recyclerView, false);   // to lock the CollapsingToolbarLayout

private void setAppBarDragging(final boolean isEnabled) {
        CoordinatorLayout.LayoutParams params =
                (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
        AppBarLayout.Behavior behavior = new AppBarLayout.Behavior();
        behavior.setDragCallback(new AppBarLayout.Behavior.DragCallback() {
            @Override
            public boolean canDrag(AppBarLayout appBarLayout) {
                return isEnabled;
            }
        });
        params.setBehavior(behavior);
    }

    public void unlockAppBarOpen() {
        appBarLayout.setExpanded(true, false);
        appBarLayout.setActivated(true);
        setAppBarDragging(false);
    }

    public void lockAppBarClosed() {
        appBarLayout.setExpanded(false, false);
        appBarLayout.setActivated(false);
        setAppBarDragging(false);

    }