android - RecyclerView 在 NestedScrollView 中使用时不会回收 View

Question

我在 NestedScrollView 中使用 RecyclerView。我还为 recyclerview

将 setNestedScrollingEnabled 设置为 false

支持较低的API

ViewCompat.setNestedScrollingEnabled(mRecyclerView, false);

现在!当用户 ScrollView 时，一切似乎都很好，但是!!! recyclerview 中的 View 不会被回收!!!并且堆大小迅速增长!

更新:RecyclerView 布局管理器是 StaggeredLayoutManager

fragment_profile.xml:

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

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

        <android.support.v4.widget.SwipeRefreshLayout
            android:id="@+id/profileSwipeRefreshLayout"
            android:layout_width="match_parent"
            android:layout_height="match_parent" >

                <!-- RecyclerView and NestedScrollView -->
                <include layout="@layout/fragment_profile_details" />

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

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

fragment_profile_details.xml:

<LinearLayout
    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:id="@+id/rootLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:orientation="vertical" >

        <android.support.v4.widget.NestedScrollView
            android:id="@+id/nested_scrollbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_gravity="fill_vertical"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            android:fillViewport="true"
            android:scrollbars="none" >

                <LinearLayout
                    android:id="@+id/nested_scrollbar_linear"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:descendantFocusability="blocksDescendants"
                    android:orientation="vertical" >

                        <android.support.v7.widget.CardView
                            android:id="@+id/profileCardview"
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            app:cardBackgroundColor="@color/card_backgroind"
                            app:cardCornerRadius="0dp"
                            app:cardElevation="0dp" >

                            <!-- Profile related stuff like avatar and etc. --->

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

                        <android.support.v7.widget.RecyclerView
                            android:id="@+id/list_view"
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:layout_marginBottom="@dimen/four"
                            android:layout_marginEnd="@dimen/four"
                            android:layout_marginLeft="@dimen/four"
                            android:layout_marginRight="@dimen/four"
                            android:layout_marginStart="@dimen/four"
                            android:layout_marginTop="@dimen/four"
                            app:layout_behavior="@string/appbar_scrolling_view_behavior"
                            android:clipToPadding="false" />

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

ProfileFragment.java:

mAdapter        = new MainAdapter(getActivity(), glide, Data);

listView        = (RecyclerView) view.findViewById(R.id.list_view);

ViewCompat.setNestedScrollingEnabled(listView, false);  
listView.setAdapter(mAdapter);

mStaggeredLM    = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);
mStaggeredLM.setGapStrategy(StaggeredGridLayoutManager.GAP_HANDLING_MOVE_ITEMS_BETWEEN_SPANS);

listView.setLayoutManager(mStaggeredLM);

mScroll.setOnScrollChangeListener(new OnScrollChangeListener() {

        @Override
        public void onScrollChange(NestedScrollView arg0, int arg1, int arg2, int arg3, int arg4) {

            View view   = (View) mScroll.getChildAt(mScroll.getChildCount() - 1);
            int diff    = (view.getBottom() - ( mScroll.getHeight() + mScroll.getScrollY()));

            if(diff == 0){

                int visibleItemCount            = mStaggeredLM.getChildCount();
                int totalItemCount              = mStaggeredLM.getItemCount();

                int[] lastVisibleItemPositions  = mStaggeredLM.findLastVisibleItemPositions(null);
                int lastVisibleItemPos  = getLastVisibleItem(lastVisibleItemPositions);

                Log.e("getChildCount", String.valueOf(visibleItemCount));
                Log.e("getItemCount", String.valueOf(totalItemCount));
                Log.e("lastVisibleItemPos", String.valueOf(lastVisibleItemPos));

                if ((visibleItemCount + 5) >= totalItemCount) {

                    mLoadMore.setVisibility(View.VISIBLE);
                    Log.e("LOG", "Last Item Reached!");
                }

                mMore = true;
                mFresh = false;
                mRefresh = false;
                getPosts();
            }

        }

    });

P.s : 我已经为 ScrollView 设置了更多负载，因为 recyclerview 会连续执行并且无法停止!

感谢任何帮助

Answer 1

这是因为我们有一个回收器 View ，它在 ScrollView 中具有滚动行为。 (在卷轴内滚动)

我认为解决此问题的最佳方法是将您的 profileCardview 作为回收站 View 中的标题，然后删除嵌套的 ScrollView 。

如果它是一个 ListView ，那么它就像 listView.addHeaderView(profileCardView) 一样简单，但是对于 Recycler View ，没有 addheadview 等效项。因此，您可以引用以下链接来更改您的实现。

Is there an addHeaderView equivalent for RecyclerView?