滚动SwipeRefreshLayout with RecyclerView Refresh anywhere in android 2.2

Question

我的布局有问题，我在里面创建了带有 RecyclerView 的 SwipeRefreshLayout。 在 android 4.2.2+ 中一切正常，但在 andorid 2.3.4 中我无法向上滚动，因为在 RecyclerView 的任何地方它都会刷新，我必须向下滚动然后向上滚动。

这是我的代码：

<android.support.v4.widget.SwipeRefreshLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/forum_swipe_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    <android.support.v7.widget.RecyclerView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/LVP"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:gravity="center" />
</android.support.v4.widget.SwipeRefreshLayout>

我发现了这个问题： https://code.google.com/p/android/issues/detail?id=78191但没有解决方案。 知道如何解决吗？

Answer 1

覆盖RecyclerView的方法OnScrollStateChanged

 mRecyclerView.setOnScrollListener(new RecyclerView.OnScrollListener() {

            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                // TODO Auto-generated method stub
                //super.onScrollStateChanged(recyclerView, newState);
               try {
                   int firstPos = mLayoutManager.findFirstCompletelyVisibleItemPosition();
                   if (firstPos > 0) {
                       mSwipeRefreshLayout.setEnabled(false);
                   } else {
                       mSwipeRefreshLayout.setEnabled(true);
                       if(mRecyclerView.getScrollState() == 1)
                           if(mSwipeRefreshLayout.isRefreshing())
                            mRecyclerView.stopScroll();
                   }

               }catch(Exception e) {
                   Log.e(TAG, "Scroll Error : "+e.getLocalizedMessage());
               }
            }

检查刷卡刷新是否刷新并尝试向上滚动然后出现错误，因此当刷卡刷新时我会尝试这样做mRecyclerView.stopScroll();

Answer 2

不幸的是，这是一个已知问题，将在未来版本中修复。

https://code.google.com/p/android/issues/detail?id=78191

同时，如果您需要紧急修复， canChildScrollUp在SwipeRefreshLayout.java覆盖SwipeRefreshLayout.java并调用recyclerView.canScrollVertically(mTarget, -1) 。 因为在姜饼之后添加了canScrollVertically ，所以您还需要复制该方法并在recyclerview中实现。

或者，如果您使用的是LinearLayoutManager，则可以调用findFirstCompletelyVisibleItemPosition 。

抱歉给你带来不便。

Answer 3

我使用以下代码修复了向上滚动问题：

private RecyclerView.OnScrollListener scrollListener = new RecyclerView.OnScrollListener() {
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        LinearLayoutManager manager = ((LinearLayoutManager)recyclerView.getLayoutManager());
        boolean enabled =manager.findFirstCompletelyVisibleItemPosition() == 0;
        pullToRefreshLayout.setEnabled(enabled);
    }
};

然后，您需要使用setOnScrollListener或addOnScrollListener具体取决于您是否有一个或多个侦听器。

Answer 4

您可以根据recyclerview的滚动功能禁用/启用刷新布局

    public class RecyclerSwipeRefreshHelper extends RecyclerView.OnScrollListener{

    private static final int DIRECTION_UP = -1;


    private final SwipeRefreshLayout refreshLayout;

    public RecyclerSwipeRefreshHelper(
            SwipeRefreshLayout refreshLayout) {
        this.refreshLayout = refreshLayout;
    }


    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
       refreshLayout.setEnabled((recyclerView.canScrollVertically(DIRECTION_UP)));
    }
}

Answer 5

您可以在SwipeRefreshLayout中覆盖方法canChildScrollUp（），如下所示：

public boolean canChildScrollUp() {
    if (mTarget instanceof RecyclerView) {
        final RecyclerView recyclerView = (RecyclerView) mTarget;
        RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
        if (layoutManager instanceof LinearLayoutManager) {
            int position = ((LinearLayoutManager) layoutManager).findFirstCompletelyVisibleItemPosition();
            return position != 0;
        } else if (layoutManager instanceof StaggeredGridLayoutManager) {
            int[] positions = ((StaggeredGridLayoutManager) layoutManager).findFirstCompletelyVisibleItemPositions(null);
            for (int i = 0; i < positions.length; i++) {
                if (positions[i] == 0) {
                    return false;
                }
            }
        }
        return true;
    } else if (android.os.Build.VERSION.SDK_INT < 14) {
        if (mTarget instanceof AbsListView) {
            final AbsListView absListView = (AbsListView) mTarget;
            return absListView.getChildCount() > 0
                    && (absListView.getFirstVisiblePosition() > 0 || absListView.getChildAt(0)
                            .getTop() < absListView.getPaddingTop());
        } else {
            return mTarget.getScrollY() > 0;
        }
    } else {
        return ViewCompat.canScrollVertically(mTarget, -1);
    }
}

Answer 6

基于@wrecker的答案（ https://stackoverflow.com/a/32318447/7508302 ）。

在Kotlin我们可以使用扩展方法。 所以：

class RecyclerViewSwipeToRefresh(private val refreshLayout: SwipeToRefreshLayout) : RecyclerView.OnScrollListener() {
    companion object {
        private const val DIRECTION_UP = -1
    }

    override fun onScrolled(recyclerView: RecyclerView?, dx: Int, dy: Int) {
        super.onScrolled(recyclerView, dx, dy)
        refreshLayout.isEnabled = !(recyclerView?.canScrollVertically(DIRECTION_UP) ?: return)
    }
}

让我们在RecyclerView中添加扩展方法，以便将此修复程序轻松应用于RV。

fun RecyclerView.fixSwipeToRefresh(refreshLayout: SwipeRefreshLayout): RecyclerViewSwipeToRefresh {
    return RecyclerViewSwipeToRefresh(refreshLayout).also {
        this.addOnScrollListener(it)
    }
}

现在，我们可以使用以下方法修复recyclerView：

recycler_view.apply {
     ...
     fixSwipeToRefresh(swipe_container)
     ...
}

Answer 7

以下代码对我有用，请确保它位于 binding.refreshDiscoverList.setOnRefreshListener{} 方法下方。

 binding.swipeToRefreshLayout.setOnChildScrollUpCallback(object : SwipeRefreshLayout.OnChildScrollUpCallback {
        override fun canChildScrollUp(parent: SwipeRefreshLayout, child: View?): Boolean {
            if (binding.rvDiscover != null) {
                return binding.recyclerView.canScrollVertically(-1)
            }
            return false
        }
    })