android - 如何将 RecyclerView 放入 NestedScrollView？

Question

通过创建NestedScrollView，您可以将滚动视图放在另一个滚动视图中，只要它们正确实现NestedScrollingChild和NestedScrollingParent。

（这是不错的设计模式“Ian Lake（来自 Google）实际上建议在RecyclerView此处放置一个嵌套滚动视图：plus.google.com/u/0/+AndroidDevelopers/posts/9kZ3SsXdT2T”）

我想把RecyclerView放在NestedScrollView里面，幸运的是 RecyclerView 实现了 NestedScrollingChild，所以你可以把它放在NestedScrollView里面。

public class RecyclerView extends ViewGroup implements ScrollingView, NestedScrollingChild

我读过这些帖子：

如何在 NestedScrollView 中使用 RecyclerView？

在 CoordinatorLayout 内使用 NestedScrollView、RecyclerView（水平）进行 NestedScrolling

但是大多数投票解决方案的问题是，它会调用所有的项目，RecyclerView例如，如果它是一个无休止的 RecyclerView 并且当用户到达列表的末尾时，您想要发出网络请求，然后使用该解决方案RecyclerView重复调用服务器因为它会自动到达RecyclerView.

无论如何，如何设置参数以便我可以放在RecyclerView里面NestedScrollView。（实际上我想把一个像framelayout或relativelayout这样的视图组作为nestedscrollview的一个孩子，然后我想把recyclerview放在framelayout或relativelayout中）

当我放入RecyclerView里面NestedScrollView时，什么都没有显示。

---

为了创建示例项目，您可以使用cheesesquare并将其更改CheeseDetailActivity为具有 RecyclerView。

---

虽然BNK的答案不正确，但BNK已经尝试了很多。所以我奖励他赏金。仍在寻找好的解决方案....

Answer 1

以下是我的新更新答案：

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

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

            <android.support.v7.widget.CardView
                android:id="@+id/cardview1"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_margin="@dimen/card_margin">

                <LinearLayout
                    style="@style/Widget.CardContent"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content">

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:text="Info CardView1"
                        android:textAppearance="@style/TextAppearance.AppCompat.Title" />

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:text="@string/cheese_ipsum" />

                </LinearLayout>

            </android.support.v7.widget.CardView>

            <android.support.v7.widget.CardView
                android:id="@+id/cardview2"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_below="@+id/cardview1"
                android:layout_margin="@dimen/card_margin">

                <LinearLayout
                    style="@style/Widget.CardContent"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content">

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:text="Info CardView2"
                        android:textAppearance="@style/TextAppearance.AppCompat.Title" />

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:text="@string/cheese_ipsum" />

                </LinearLayout>

            </android.support.v7.widget.CardView>

            <android.support.v7.widget.RecyclerView
                android:id="@+id/recyclerview"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_below="@+id/cardview2"
                android:clipToPadding="false"
                android:paddingTop="0dp"/>

        </RelativeLayout>

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

在活动中：

        RecyclerViewAdapter recyclerViewAdapter = new RecyclerViewAdapter(true); // true: with header
        RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerview);            
        final MyLinearLayoutManager layoutManager = new MyLinearLayoutManager(this, LinearLayoutManager.VERTICAL, false, getScreenHeight(this));
        // final CustomLinearLayoutManager layoutManager = new CustomLinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setAdapter(recyclerViewAdapter);  
        // recyclerView.setNestedScrollingEnabled(false); // Disables scrolling for RecyclerView, however, CustomLinearLayoutManager used instead of MyLinearLayoutManager

我也更新到My GitHub 的示例项目

截屏：

---

Answer 2

这是仅在您确实需要加载更多数据时才调用服务器的解决方案。通过这种方式，您可以将无尽的 RecyclerView 和许多其他视图放入 NestedScrollView。对我来说，它运作良好。

1.创建EndlessParentScrollListener类来处理来自 NestedSrollView 的滚动事件。

public abstract class EndlessParentScrollListener implements NestedScrollView.OnScrollChangeListener {
        // The current offset index of data you have loaded
        private int currentPage = 0;
        // The total number of items in the dataset after the last load
        private int previousTotalItemCount = 0;
        // True if we are still waiting for the last set of data to load.
        private boolean loading = true;
        // Sets the starting page index
        private int startingPageIndex = 0;
        // The minimum amount of pixels to have below your current scroll position
        // before loading more.
        private int visibleThresholdDistance = 300;

        RecyclerView.LayoutManager mLayoutManager;

        public EndlessParentScrollListener(RecyclerView.LayoutManager layoutManager) {
            this.mLayoutManager = layoutManager;
        }

        @Override
        public void onScrollChange(NestedScrollView scrollView, int x, int y, int oldx, int oldy) {
            // We take the last son in the scrollview
            View view = scrollView.getChildAt(scrollView.getChildCount() - 1);
            int distanceToEnd = (view.getBottom() - (scrollView.getHeight() + scrollView.getScrollY()));

            int totalItemCount = mLayoutManager.getItemCount();
            // If the total item count is zero and the previous isn't, assume the
            // list is invalidated and should be reset back to initial state
            if (totalItemCount < previousTotalItemCount) {
                this.currentPage = this.startingPageIndex;
                this.previousTotalItemCount = totalItemCount;
                if (totalItemCount == 0) {
                    this.loading = true;
                }
            }

            // If it’s still loading, we check to see if the dataset count has
            // changed, if so we conclude it has finished loading and update the current page
            // number and total item count.
            if (loading && (totalItemCount > previousTotalItemCount)) {
                loading = false;
                previousTotalItemCount = totalItemCount;
            }

            // If it isn’t currently loading, we check to see if we have breached
            // the visibleThreshold and need to reload more data.
            // If we do need to reload some more data, we execute onLoadMore to fetch the data.
            // threshold should reflect how many total columns there are too
            if (!loading && distanceToEnd <= visibleThresholdDistance) {
                currentPage++;
                onLoadMore(currentPage, totalItemCount);
                loading = true;
            }
        }

        // Defines the process for actually loading more data based on page
        public abstract void onLoadMore(int page, int totalItemsCount);
    }

2.设置监听

private void initRecycler() {  
        //TODO init recycler adapter here

        recycler.setNestedScrollingEnabled(false);          
        LinearLayoutManager _layoutManager = new LinearLayoutManager(this);
        recycler.setLayoutManager(_layoutManager);
        NestedScrollView scrollView = (NestedScrollView) findViewById(R.id.scrollView);
        scrollView.setOnScrollChangeListener(new EndlessParentScrollListener(_layoutManager) {
                @Override
                public void onLoadMore(int page, int totalItemsCount) {                     
                    if (loadedItemCount < serverItemsCount)
                        customLoadMoreDataFromApi();
                }
            });
        customLoadMoreDataFromApi();
    }

短 xml 如果有人觉得它有用：

<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:background="@android:color/background_light"
        android:fitsSystemWindows="true">


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

        <android.support.v4.widget.NestedScrollView
            android:id="@+id/scrollView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            android:scrollbars="vertical"
            android:scrollbarAlwaysDrawVerticalTrack="true"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical"
                android:scrollbarAlwaysDrawVerticalTrack="false"
                android:scrollbars="vertical">

                <!-- some views goes here-->

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

                <!-- and possibly here-->

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

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

Answer 3

所以直接把 RecyclerView 放在 NestedScrollView 里面会很遗憾什么都不显示。但是，有一种方法可以将 recyclerview 间接放在 NestedScrollView 中 - 只需使用 frameLayout 作为第三方来保存您的 recyclerview。

这是在您的活动类中包含嵌套回收器视图的框架布局：

    <FrameLayout
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true"
        tools:context=".ExampleFragment"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <android.support.v4.widget.NestedScrollView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fillViewport="true"
            >
        </android.support.v4.widget.NestedScrollView>
   </FrameLayout>

将您的片段放入框架布局中（代码位于活动类中）：

 ExampleFragment exampleFragment = new ExampleFragment();

    FragmentManager fm = getSupportFragmentManager();
    FragmentTransaction ft = fm.beginTransaction();
    ft.add(R.id.container, exampleFragment);
    ft.commit();

在你的exampleFragment中，你可以把你的 recyclerview.

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/post_container"
        android:background="#E0E0E0">

            <android.support.v7.widget.RecyclerView
                android:id="@+id/my_recycler_view"
                android:scrollbars="vertical"

                android:layout_width="match_parent"
                android:layout_height="match_parent">
            </android.support.v7.widget.RecyclerView>


    </RelativeLayout>

这是片段代码：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    super.onCreateView(inflater, container, savedInstanceState);
            llLayout = (RelativeLayout) inflater.inflate(R.layout.example_fragment_layout, container, false);
                    mRecyclerView = (RecyclerView) llLayout.findViewById(R.id.my_recycler_view);

以下是您应该拥有的CheeseSquare XML 布局：

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

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/detail_backdrop_height"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        android:fitsSystemWindows="true">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/collapsing_toolbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed"
            android:fitsSystemWindows="true"
            app:contentScrim="?attr/colorPrimary"
            app:expandedTitleMarginStart="48dp"
            app:expandedTitleMarginEnd="64dp">

            <ImageView
                android:id="@+id/backdrop"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:scaleType="centerCrop"
                android:fitsSystemWindows="true"
                app:layout_collapseMode="parallax" />

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

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

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

   <FrameLayout
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true"
        tools:context=".ExampleFragment"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <android.support.v4.widget.NestedScrollView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fillViewport="true"
            >
        </android.support.v4.widget.NestedScrollView>
   </FrameLayout>

    <android.support.design.widget.FloatingActionButton
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        app:layout_anchor="@id/appbar"
        app:layout_anchorGravity="bottom|right|end"
        android:src="@drawable/ic_discuss"
        android:layout_margin="@dimen/fab_margin"
        android:clickable="true"/>

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

Answer 4

我已经浪费了至少一周的时间，唯一有效的解决方案是删除nestedscrollview. 我知道这不是在recyclerview里面添加这个特定问题的答案nestedscrollview，而是要让 recyclerview 真正回收视图，你必须删除nestedscrollview. 如果您碰巧有多个view内部而不仅仅是recyclerview，您必须通过设置不同的视图将它们添加为项目recyclerview，然后添加

app:layout_behavior="@string/appbar_scrolling_view_behavior"

到 recyclerview 或父级recyclerview（父级不能有除 Recyclerview 之外的任何其他视图才能正常工作）。

就我而言，要求如下：

  <androidx.coordinatorlayout.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:fitsSystemWindows="true"
        app:layout_constraintTop_toTopOf="parent">

        <!-- Scrollable view here -->

        <com.google.android.material.appbar.AppBarLayout
            ....   >

            <com.google.android.material.appbar.CollapsingToolbarLayout
                ....>

                <androidx.appcompat.widget.Toolbar
                    ....>

                    <include
                        android:id="@+id/toolbar_header_view"
                        .... />
                </androidx.appcompat.widget.Toolbar>

                <include layout="@layout/widget_header" />
            </com.google.android.material.appbar.CollapsingToolbarLayout>
        </com.google.android.material.appbar.AppBarLayout>

        <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
            ....>
            <LinearLayout orientation="vertical" ....>
                <View .../>  <!-- I needed to have these two views along with recyclerview and i wanted them to do nestedscroll along with recyclerview -->
                <View .../>
                <androidx.recyclerview.widget.RecyclerView
                .... />
        </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
    </androidx.coordinatorlayout.widget.CoordinatorLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

我之前需要有两个视图recyclerview，我希望它们与recyclerview. 唯一有效的方法是将这些删除到视图并将它们添加为 的前两项recyclerview，然后添加

app:layout_behavior="@string/appbar_scrolling_view_behavior"

到swipetorefresh布局

希望这可以帮助某人。如果需要，我会添加更多信息。