RecyclerView:检测到不一致。无效的项目位置-这是为什么？

Question

我们的 QA 检测到一个错误：发生了以下与 RecyclerView 相关的崩溃：'

Java . lang . indexoutofboundsexception:检测到不一致。无效的项目位置2(偏移量:2)。状态:3

一个残酷的解决方法可能是在异常发生时捕获它，并从头开始重新创建RecycleverView实例，以避免处于损坏状态。

但是，如果可能的话，我想更好地理解这个问题（也许从根源上修复它），而不是掩盖它。

这个错误很容易重现滚动持续快速造成这种崩溃，但当它发生时是致命的。

我的工作代码是:

public class MoviesGridRecyclerViewDataAdapter  extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

public static final int VIEW_ITEM = 1;
public static final int VIEW_PROG = -1;
private static final int FADE_DURATION = 500;
int pastVisiblesItems, visibleItemCount, totalItemCount;
private List<VideoEntity> dataList;
private FragmentActivity activity;
private int visibleThreshold = 1;
//private int lastVisibleItem, totalItemCount;
//private boolean loading = false;
private OnLoadMoreListener onLoadMoreListener;
private RecyclerView.OnScrollListener recyclerciewScrollListener;
private RecyclerView recyclerView;
private boolean followLargeItemOnDataRender;
private boolean loading = false;
private boolean isLiveChannel = false;

public MoviesGridRecyclerViewDataAdapter(FragmentActivity fragmentActivity, final List<VideoEntity> dataList, RecyclerView recycler, boolean followLargeItemOnOddData, boolean isLiveChannels) {
    this.dataList = dataList;
    this.activity = fragmentActivity;
    this.followLargeItemOnDataRender = followLargeItemOnOddData;
    this.recyclerView = recycler;
    isLiveChannel = isLiveChannels;

    Log.e("VideoGridRVDataAdapter", "True");

    if (this.recyclerView.getLayoutManager() instanceof GridLayoutManager) {

        final GridLayoutManager gridLayoutManager = (GridLayoutManager) this.recyclerView.getLayoutManager();
        recyclerciewScrollListener = new RecyclerView.OnScrollListener() {

            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);

                if (dy > 0) //check for scroll down
                {
                    visibleItemCount = gridLayoutManager.getChildCount();
                    totalItemCount = gridLayoutManager.getItemCount();
                    pastVisiblesItems = gridLayoutManager.findFirstVisibleItemPosition();

                    if (!loading) {
                        if ((visibleItemCount + pastVisiblesItems) >= totalItemCount) {
                            loading = true;


                            if (onLoadMoreListener != null) {
                                onLoadMoreListener.onLoadMore(visibleItemCount + pastVisiblesItems);
                            }
                        }
                    }
                }
            }
        };

        this.recyclerView.addOnScrollListener(recyclerciewScrollListener);
    }
}


public void notifyDataLoadingStartProgress() {
    dataList.add(null);
    notifyItemInserted(dataList.size() - 1);
}

public void notifyDataLoaded() {
    dataList.remove(dataList.size() - 1);
    notifyItemRemoved(dataList.size());
    setLoaded();
}


public void resetItems(@NonNull List<VideoEntity> newDataSet) {
    loading = false;
    pastVisiblesItems = visibleItemCount = totalItemCount = 0;

    dataList.clear();
    addItems(newDataSet);
}

public void addItems(@NonNull List<VideoEntity> newDataSetItems) {
    dataList.addAll(newDataSetItems);
    postAndNotifyAdapter(new Handler());
}



public void addItem(VideoEntity item) {
    if (!dataList.contains(item)) {
        dataList.add(item);
        notifyItemInserted(dataList.size() - 1);
    }
}

public void removeItem(VideoEntity item) {
    int indexOfItem = dataList.indexOf(item);
    if (indexOfItem != -1) {
        this.dataList.remove(indexOfItem);
        notifyItemRemoved(indexOfItem);
    }
}

private void postAndNotifyAdapter(final Handler handler) {
    handler.post(new Runnable() {
        @Override
        public void run() {
            if (!recyclerView.isComputingLayout()) {
                try {
                    recyclerView.getRecycledViewPool().clear();
                    notifyDataSetChanged();
                } catch (IndexOutOfBoundsException ex) {
                }

            } else {
                postAndNotifyAdapter(handler);
            }
        }
    });
}

public void destroy() {
    this.recyclerView.removeOnScrollListener(recyclerciewScrollListener);
}


@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
    RecyclerView.ViewHolder vh;
    View v;
    if (viewType == VIEW_PROG) {
        v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.item_progressbar, viewGroup, false);
        vh = new ProgressViewHolder(v);

    } else {
        Integer layoutResourceId;

        if (isLiveChannel) {
            layoutResourceId = R.layout.item_video_grid_norma_hs_overfow_overdraw;

        } else {
            layoutResourceId = R.layout.item_video_linear_overdraw;

        }
        v = LayoutInflater.from(viewGroup.getContext()).inflate(layoutResourceId, viewGroup, false);
        vh = new MoviesItemRowHolder(this, dataList, v, activity);
    }
    return vh;
}

@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int i) {

    if (holder instanceof MoviesItemRowHolder) {
        VideoEntity singleItem = dataList.get(i);
        ((MoviesItemRowHolder) holder).bind(singleItem,dataList);
        //setScaleAnimation(holder.itemView);
    } else {
        ((ProgressViewHolder) holder).progressBar.setIndeterminate(true);
    }
}

public boolean isLoading() {
    return loading;
}

public void setLoaded() {
    loading = false;
}

private void setFadeAnimation(View view) {
    AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
    anim.setDuration(FADE_DURATION);
    view.startAnimation(anim);
}

private void setScaleAnimation(View view) {
    ScaleAnimation anim = new ScaleAnimation(0.0f, 1.0f, 0.0f, 1.0f, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);
    anim.setDuration(FADE_DURATION);
    view.startAnimation(anim);
}

/**
 * Return the view type of the item at <code>position</code> for the purposes
 * of view recycling.
 * <p/>
 * <p>The default implementation of this method returns 0, making the assumption of
 * a single view type for the adapter. Unlike ListView adapters, types need not
 * be contiguous. Consider using id resources to uniquely identify item view types.
 *
 * @param position position to query
 * @return integer value identifying the type of the view needed to represent the item at
 * <code>position</code>. Type codes need not be contiguous.
 */
@Override
public int getItemViewType(int position) {
    //return position;

    return dataList.get(position) != null ? position : VIEW_PROG;
}

@Override
public int getItemCount() {
    return (null != dataList ? dataList.size() : 0);
}

public void setOnLoadMoreListener(OnLoadMoreListener onLoadMoreListener) {
    this.onLoadMoreListener = onLoadMoreListener;
}

public List<VideoEntity> getItems() {
    return dataList;
}
}

请看看我的班级，让我知道哪里出了问题，当我快速滚动时，这个崩溃发生在更少的设备上。

堆栈跟踪是：

Fatal Exception: java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid item position 17(offset:17).state:18 android.support.v7.widget.RecyclerView{4266ee78 VFED.... .F....ID 0,0-480,625 #7f0902db app:id/recycler_view_list}, adapter:com.tapmad.tapmadtv.f.e@425896c0, layout:com.tapmad.tapmadtv.WrapContentLinearLayoutManager@424092b0, context:com.tapmad.tapmadtv.activities.SectionMoreActivityHS@4244c478
   at android.support.v7.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline + 5923(RecyclerView.java:5923)
   at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition + 5858(RecyclerView.java:5858)
   at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition + 5854(RecyclerView.java:5854)
   at android.support.v7.widget.LinearLayoutManager$LayoutState.next + 2230(LinearLayoutManager.java:2230)
   at android.support.v7.widget.GridLayoutManager.layoutChunk + 557(GridLayoutManager.java:557)
   at android.support.v7.widget.LinearLayoutManager.fill + 1517(LinearLayoutManager.java:1517)
   at android.support.v7.widget.LinearLayoutManager.scrollBy + 1331(LinearLayoutManager.java:1331)
   at android.support.v7.widget.LinearLayoutManager.scrollVerticallyBy + 1075(LinearLayoutManager.java:1075)
   at android.support.v7.widget.GridLayoutManager.scrollVerticallyBy + 382(GridLayoutManager.java:382)
   at android.support.v7.widget.RecyclerView.scrollStep + 1832(RecyclerView.java:1832)
   at android.support.v7.widget.RecyclerView$ViewFlinger.run + 5067(RecyclerView.java:5067)
   at android.view.Choreographer$CallbackRecord.run + 791(Choreographer.java:791)
   at android.view.Choreographer.doCallbacks + 591(Choreographer.java:591)
   at android.view.Choreographer.doFrame + 560(Choreographer.java:560)
   at android.view.Choreographer$FrameDisplayEventReceiver.run + 777(Choreographer.java:777)
   at android.os.Handler.handleCallback + 725(Handler.java:725)
   at android.os.Handler.dispatchMessage + 92(Handler.java:92)
   at android.os.Looper.loop + 176(Looper.java:176)
   at android.app.ActivityThread.main + 5317(ActivityThread.java:5317)
   at java.lang.reflect.Method.invokeNative(Method.java)
   at java.lang.reflect.Method.invoke + 511(Method.java:511)
   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run + 1102(ZygoteInit.java:1102)
   at com.android.internal.os.ZygoteInit.main + 869(ZygoteInit.java:869)
   at dalvik.system.NativeStart.main(NativeStart.java)

任何领导高度赞赏谢谢。

Answer 1

调用< code > notifyDataSetChanged()；每当您像在< code>resetItems()方法中一样操作完整列表时

Answer 2

将此代码添加到方法 onBindViewHolder 中

holder.setIsRecyclable(true);

在将适配器设置为回收器之前查看清除过去的位置并使用代码查看

recyclerView.getRecycledViewPool().clear();

它工作正常

Answer 3

我在你的代码中发现了问题

问题是，当您清除数组列表时

dataList.clear();

您必须通知适配器数据集已被更改。否则适配器不知道数据集的清除，其计算出错

dataList.clear();
notifyDataSetChanged();

因此，recyclerview适配器将知道发生了数据清除，并将重新计算头寸。当你添加新数据时，不会有任何不一致。