如果您只是想要平滑滚动，那么不需要自定义滚动，正如我之前在其他线程中提到的那样。
当您想要开始平滑滚动时，添加如下行
appBarLayout.setExpanded(false, /*true if animation required else false*/true);
recyclerView.smoothScrollToPosition(position);
附加信息
另外，我没有看到任何RecyclerView在你的布局中，你很可能已经将它保留在其中LinearLayout这又是一部分CollapsingToolbarLayout。我完全不知道你为什么保留RecyclerView作为...的一部分CollapsingToolbarLayout。我将给出我正在使用的布局（简化的布局）。
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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.CoordinatorLayout
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="@+id/app_bar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:expanded="true"
app:layout_behavior="com.company.app.custom.CustomRecyclerScrollBehavior">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginEnd="64dp"
app:expandedTitleMarginStart="48dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<FrameLayout
android:id="@+id/header_frame"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_collapseMode="parallax"
app:layout_collapseParallaxMultiplier="0.8">
<com.company.app.custom.CustomViewPager
android:id="@+id/view_pager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:calculation="height"
app:height_ratio="@integer/product_listitem_img_width_ratio"
app:width_ratio="@integer/product_listitem_img_height_ratio" />
<com.company.app.custom.CustomImageView
android:id="@+id/img_stock_layer"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:scaleType="fitXY"
android:src="@color/transparent_app_black"
android:visibility="gone"
app:calculation_type="height"
app:ratio_height="@integer/product_listitem_img_width_ratio"
app:ratio_width="@integer/product_listitem_img_height_ratio" />
<com.inneex.www.customfonts.FontTextView
android:id="@+id/lbl_out_of_stock"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="@string/out_of_stock"
android:textColor="?android:attr/textColorPrimaryInverse"
android:textSize="13sp"
android:visibility="gone"
app:customFont="@string/font_ss_semibold" />
<LinearLayout
android:id="@+id/ll_page"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|center_horizontal"
android:orientation="horizontal"
android:paddingBottom="@dimen/inspire_detail_oval_margin_bottom" />
</FrameLayout>
<android.support.v7.widget.Toolbar
android:id="@+id/main_toolbar"
android:layout_width="match_parent"
android:layout_height="@dimen/toolbar_height"
android:background="?attr/colorPrimary"
app:layout_anchor="@id/header_frame"
app:layout_collapseMode="pin"
app:title="">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal">
<com.inneex.www.customfonts.FontTextView
android:id="@+id/lbl_toolbar_product_name"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_weight="1"
android:ellipsize="end"
android:lines="1"
android:maxLines="1"
android:minLines="1"
android:textColor="?android:attr/textColorPrimary"
android:textSize="18sp"
app:customFont="@string/font_ss_semibold" />
</LinearLayout>
</android.support.v7.widget.Toolbar>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<ImageView
android:id="@+id/img_back"
android:layout_width="@dimen/toolbar_height"
android:layout_height="@dimen/toolbar_height"
android:layout_gravity="top|start"
android:scaleType="fitXY"
android:src="@drawable/back"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/white"
app:layout_behavior="@string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
<include
layout="@layout/listitem_product_detail_buy_cheap"
android:layout_width="match_parent"
android:layout_height="@dimen/product_detail_button_buy_cheap_height"
android:layout_alignParentBottom="true"
android:layout_gravity="bottom" />
</RelativeLayout>
FrameLayout带身份证header_frame负责大工具栏，该工具栏在滚动时会折叠。Toolbar带身份证main_toolbar负责工具栏的折叠视图。RecyclerView是下面的AppBarLayout. ImageView用于后退按钮，折叠后将显示Toolbar被展示。
作为参考，为了使滚动平滑，我添加了CustomRecyclerScrollBehavior我之前和你谈过。就是这样
import android.content.Context;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.CoordinatorLayout;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.view.View;
import java.lang.ref.WeakReference;
import java.util.HashMap;
import java.util.Map;
/**
* Created by jimitpatel on 13/12/16.
*/
public class CustomRecyclerScrollBehavior extends AppBarLayout.Behavior {
private Map<RecyclerView, RecyclerViewScrollListener> scrollListenerMap = new HashMap<>(); //keep scroll listener map, the custom scroll listener also keep the current scroll Y position.
public CustomRecyclerScrollBehavior() {
}
public CustomRecyclerScrollBehavior(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
*
* @param coordinatorLayout
* @param child The child that attached the behavior (AppBarLayout)
* @param target The scrolling target e.g. a recyclerView or NestedScrollView
* @param velocityX
* @param velocityY
* @param consumed The fling should be consumed by the scrolling target or not
* @return
*/
@Override
public boolean onNestedFling(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, float velocityX, float velocityY, boolean consumed) {
if (target instanceof RecyclerView) {
final RecyclerView recyclerView = (RecyclerView) target;
if (scrollListenerMap.get(recyclerView) == null) {
RecyclerViewScrollListener recyclerViewScrollListener = new RecyclerViewScrollListener(coordinatorLayout, child, this);
scrollListenerMap.put(recyclerView, recyclerViewScrollListener);
recyclerView.addOnScrollListener(recyclerViewScrollListener);
}
scrollListenerMap.get(recyclerView).setVelocity(velocityY);
consumed = scrollListenerMap.get(recyclerView).getScrolledY() > 0; //recyclerView only consume the fling when it's not scrolled to the top
}
return super.onNestedFling(coordinatorLayout, child, target, velocityX, velocityY, consumed);
}
private static class RecyclerViewScrollListener extends RecyclerView.OnScrollListener {
private int scrolledY;
private boolean dragging;
private float velocity;
private WeakReference<CoordinatorLayout> coordinatorLayoutRef;
private WeakReference<AppBarLayout> childRef;
private WeakReference<CustomRecyclerScrollBehavior> behaviorWeakReference;
public RecyclerViewScrollListener(CoordinatorLayout coordinatorLayout, AppBarLayout child, CustomRecyclerScrollBehavior barBehavior) {
coordinatorLayoutRef = new WeakReference<>(coordinatorLayout);
childRef = new WeakReference<>(child);
behaviorWeakReference = new WeakReference<>(barBehavior);
}
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
dragging = newState == RecyclerView.SCROLL_STATE_DRAGGING;
}
public void setVelocity(float velocity) {
this.velocity = velocity;
}
public int getScrolledY() {
return scrolledY;
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
scrolledY += dy;
if (scrolledY <= 0 && !dragging && childRef.get() != null && coordinatorLayoutRef.get() != null && behaviorWeakReference.get() != null) {
//manually trigger the fling when it's scrolled at the top
behaviorWeakReference.get().onNestedFling(coordinatorLayoutRef.get(), childRef.get(), recyclerView, 0, velocity, false);
}
}
}
}
此类用于维持滚动速度RecyclerView在嵌套的卷轴中。这里的投掷已经改变
希望这对你有用！
