RecyclerView java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter position. Due to changing getItemCount()
I am getting a java.lang.IndexOutOfBoundsException: Inconsistency detected with the RecyclerView, but only when I seem to fling it. When I scroll slow enough it doesn't crash on me.
I use my base adapter for many other subclasses but only certain ones crash on me. Any idea why this is happening?
EDIT
I figured out the reason this is happening is because getItemCount() changes depending on the status of my footer loading views. I believe this is causing an inconsistency when it changes and while I am scrolling.
I tested this by always returning 2 extra items for my header/footer loading views in getItemCount(). Instead of dynamically calculating the count based on their statuses. What would be a good approach to fixing this issue?
My adapter
public abstract class BaseRecyclerAdapter<T>
extends RecyclerView.Adapter<RecyclerView.ViewHolder>
implements LoadingAndErrorViewHolder.LoadingViewHolderListener {
public static final int STATUS_HIDDEN = 0;
public static final int STATUS_LOADING = 1;
public static final int STATUS_ERROR = 2;
protected static final int TYPE_HEADER_LOADING = 0;
protected static final int TYPE_FOOTER_LOADING = 1;
protected static final int TYPE_NORMAL = 2;
private static final int POSITION_TYPE_HEADER_LOADING = 0;
private BaseRecyclerAdapterListener mBaseRecyclerAdapterListener;
private final List<T> mBackingList = new ArrayList<T>();
private int mHeaderStatus = STATUS_HIDDEN;
private int mFooterStatus = STATUS_HIDDEN;
private final int mNumOfHeaderItems;
public interface BaseRecyclerAdapterListener {
void onErrorHeaderRetryClicked();
void onErrorFooterRetryClicked();
}
public BaseRecyclerAdapter() {
this(null);
}
public BaseRecyclerAdapter(BaseRecyclerAdapterListener listener) {
this(0, listener);
}
public BaseRecyclerAdapter(int numOfHeaderItems, BaseRecyclerAdapterListener listener) {
mNumOfHeaderItems = numOfHeaderItems;
mBaseRecyclerAdapterListener = listener;
setHasStableIds(true);
}
@Override
public long getItemId(int position) {
final T item = getItem(position);
if (item != null) {
return item.hashCode();
} else {
return position;
}
}
@Override
public int getItemCount() {
int count = mBackingList.size();
if (mHeaderStatus != STATUS_HIDDEN) {
count++;
}
if (mFooterStatus != STATUS_HIDDEN) {
count++;
}
return mNumOfHeaderItems + count;
}
@Override
public int getItemViewType(int position) {
final int headerAdjustment = mHeaderStatus != STATUS_HIDDEN ? 1 : 0;
if (position == 0 && mHeaderStatus != STATUS_HIDDEN) {
return TYPE_HEADER_LOADING;
} else if (position < mBackingList.size() + headerAdjustment + mNumOfHeaderItems) {
return TYPE_NORMAL;
} else {
return TYPE_FOOTER_LOADING;
}
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final LayoutInflater inflater = LayoutInflater.from(parent.getContext());
switch (viewType) {
case TYPE_HEADER_LOADING: {
return new LoadingAndErrorViewHolder(inflater.inflate(
LoadingAndErrorViewHolder.LAYOUT_ID, parent, false),
LoadingAndErrorViewHolder.TYPE_HEADER, this);
}
case TYPE_FOOTER_LOADING: {
return new LoadingAndErrorViewHolder(inflater.inflate(
LoadingAndErrorViewHolder.LAYOUT_ID, parent, false),
LoadingAndErrorViewHolder.TYPE_FOOTER, this);
}
default: {
return onCreateItemViewHolder(parent, viewType);
}
}
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
final int viewType = getItemViewType(position);
switch (viewType) {
case TYPE_HEADER_LOADING: {
((LoadingAndErrorViewHolder) holder).setStatus(mHeaderStatus);
break;
}
case TYPE_FOOTER_LOADING: {
((LoadingAndErrorViewHolder) holder).setStatus(mFooterStatus);
break;
}
default: {
onBindItemViewHolder(holder, position);
}
}
}
@Override
public void onHeaderLoadingViewHolderClick() {
if (mBaseRecyclerAdapterListener != null) {
mBaseRecyclerAdapterListener.onErrorHeaderRetryClicked();
}
}
@Override
public void onFooterLoadingViewHolderClick() {
if (mBaseRecyclerAdapterListener != null) {
mBaseRecyclerAdapterListener.onErrorFooterRetryClicked();
}
}
public T getItem(int position) {
final int headerAdjustment = mHeaderStatus != STATUS_HIDDEN ? 1 : 0;
final int adjustedPosition = position - headerAdjustment - mNumOfHeaderItems;
if (adjustedPosition < 0
|| (mFooterStatus != STATUS_HIDDEN && position == getItemCount() - 1)) {
return null;
} else {
return mBackingList.get(adjustedPosition);
}
}
public List<T> getList() {
return mBackingList;
}
public int getListSize() {
return mBackingList.size();
}
public void setList(List<T> list) {
if (list != null) {
clear();
add(list);
}
}
public void add(T item) {
if (item != null) {
mBackingList.add(item);
notifyItemInserted(getItemCount() - 1);
}
}
public void add(int index, T item) {
if (item != null) {
mBackingList.add(index, item);
notifyItemInserted(index + getItemOffset());
}
}
public void add(List<T> list) {
if (list != null) {
final int currentLastIndex;
if (mBackingList.size() > 0) {
currentLastIndex = mBackingList.size() - 1;
} else {
currentLastIndex = 0;
}
mBackingList.addAll(list);
notifyItemRangeInserted(currentLastIndex + getItemOffset(), list.size());
}
}
public void add(int index, List<T> list) {
if (list != null) {
mBackingList.addAll(index, list);
notifyItemRangeInserted(index + getItemOffset(), list.size());
}
}
public void update(int position, T item) {
mBackingList.set(position, item);
notifyItemChanged(position + getItemOffset());
}
public void remove(T item) {
if (item != null && mBackingList.remove(item)) {
notifyDataSetChanged();
}
}
public void clear() {
mBackingList.clear();
notifyDataSetChanged();
}
public void setHeaderStatus(int headerStatus) {
mHeaderStatus = headerStatus;
notifyItemChanged(POSITION_TYPE_HEADER_LOADING);
}
public void setFooterStatus(int footerStatus) {
mFooterStatus = footerStatus;
notifyItemChanged(getItemCount() - 1);
}
public void checkEndOfList(List<T> data) {
if (data.isEmpty()) {
setFooterStatus(STATUS_HIDDEN);
} else {
setFooterStatus(STATUS_LOADING);
}
}
protected int getHeaderStatus() {
return mHeaderStatus;
}
protected int getFooterStatus() {
return mFooterStatus;
}
protected abstract RecyclerView.ViewHolder onCreateItemViewHolder(ViewGroup parent, int viewType);
protected abstract void onBindItemViewHolder(RecyclerView.ViewHolder holder, int position);
private int getItemOffset() {
final int headerAdjustment = mHeaderStatus != STATUS_HIDDEN ? 1 : 0;
return headerAdjustment + mNumOfHeaderItems;
}
}
Stacktrace
06-01 10:46:36.230 11448-11448/com.fusionprojects.edmodo E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.fusionprojects.edmodo, PID: 11448
java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter positionViewHolder{dcf5c3a position=23 id=-1, oldPos=23, pLpos:-1 scrap [attachedScrap] tmpDetached no parent}
at android.support.v7.widget.RecyclerView$Recycler.validateViewHolderForOffsetPosition(RecyclerView.java:5297)
at android.support.v7.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:5479)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5440)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5436)
at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2224)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1551)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1511)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:595)
at android.support.v7.widget.RecyclerView.dispatchLayoutStep1(RecyclerView.java:3534)
at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3310)
at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3844)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.support.v4.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:636)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.support.v4.view.ViewPager.onLayout(ViewPager.java:1795)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
06-01 10:46:36.231 11448-11448/com.fusionprojects.edmodo E/AndroidRuntime: at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
at com.android.internal.policy.DecorView.onLayout(DecorView.java:726)
at android.view.View.layout(View.java:17641)
at android.view.ViewGroup.layout(ViewGroup.java:5575)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2346)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2068)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1254)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6343)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:874)
at android.view.Choreographer.doCallbacks(Choreographer.java:686)
at android.view.Choreographer.doFrame(Choreographer.java:621)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6126)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Answer
I fixed this by calling notifyDataSetChanged() in my setFooterStatus() method.