content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   * 
   *   http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.weex.ui.component.list;
  
  import android.annotation.SuppressLint;
  import android.annotation.TargetApi;
  import android.content.Context;
  import android.graphics.Color;
  import android.graphics.Point;
  import android.graphics.PointF;
  import android.os.Build;
  import android.support.annotation.NonNull;
  import android.support.annotation.Nullable;
  import android.support.v4.util.ArrayMap;
  import android.support.v4.view.MotionEventCompat;
  import android.support.v4.view.ViewCompat;
  import android.support.v7.widget.GridLayoutManager;
  import android.support.v7.widget.LinearLayoutManager;
  import android.support.v7.widget.RecyclerView;
  import android.support.v7.widget.StaggeredGridLayoutManager;
  import android.text.TextUtils;
  import android.util.SparseArray;
  import android.view.Gravity;
  import android.view.MotionEvent;
  import android.view.View;
  import android.view.ViewGroup;
  import android.view.ViewTreeObserver;
  import android.widget.FrameLayout;
  import android.widget.LinearLayout;
  
  import org.apache.weex.WXEnvironment;
  import org.apache.weex.WXSDKInstance;
  import org.apache.weex.annotation.JSMethod;
  import org.apache.weex.common.Constants;
  import org.apache.weex.common.ICheckBindingScroller;
  import org.apache.weex.common.OnWXScrollListener;
  import org.apache.weex.dom.WXAttr;
  import org.apache.weex.ui.action.BasicComponentData;
  import org.apache.weex.ui.component.AppearanceHelper;
  import org.apache.weex.ui.component.Scrollable;
  import org.apache.weex.ui.component.WXBaseRefresh;
  import org.apache.weex.ui.component.WXComponent;
  import org.apache.weex.ui.component.WXComponentProp;
  import org.apache.weex.ui.component.WXHeader;
  import org.apache.weex.ui.component.WXLoading;
  import org.apache.weex.ui.component.WXRefresh;
  import org.apache.weex.ui.component.WXVContainer;
  import org.apache.weex.ui.component.helper.ScrollStartEndHelper;
  import org.apache.weex.ui.component.helper.WXStickyHelper;
  import org.apache.weex.ui.view.listview.WXRecyclerView;
  import org.apache.weex.ui.view.listview.adapter.IOnLoadMoreListener;
  import org.apache.weex.ui.view.listview.adapter.IRecyclerAdapterListener;
  import org.apache.weex.ui.view.listview.adapter.ListBaseViewHolder;
  import org.apache.weex.ui.view.listview.adapter.RecyclerViewBaseAdapter;
  import org.apache.weex.ui.view.listview.adapter.WXRecyclerViewOnScrollListener;
  import org.apache.weex.ui.view.refresh.wrapper.BounceRecyclerView;
  import org.apache.weex.utils.WXLogUtils;
  import org.apache.weex.utils.WXResourceUtils;
  import org.apache.weex.utils.WXUtils;
  import org.apache.weex.utils.WXViewUtils;
  
  import java.util.ArrayDeque;
  import java.util.ArrayList;
  import java.util.Deque;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.regex.Pattern;
  
  /**
   * Created by sospartan on 13/12/2016.
   */
  
  public abstract class BasicListComponent<T extends ViewGroup & ListComponentView> extends
      WXVContainer<T> implements
      IRecyclerAdapterListener<ListBaseViewHolder>, IOnLoadMoreListener, Scrollable {
    public static final String TRANSFORM = "transform";
    public static final String LOADMOREOFFSET = "loadmoreoffset";
    private String TAG = "BasicListComponent";
    private int mListCellCount = 0;
    private boolean mForceLoadmoreNextTime = false;
    private static final Pattern transformPattern = Pattern.compile("([a-z]+)\\(([0-9\\.]+),?([0-9\\.]+)?\\)");
  
    private Map<String, AppearanceHelper> mAppearComponents = new HashMap<>();
    private Runnable mAppearChangeRunnable = null;
    private long mAppearChangeRunnableDelay = 50;
  
    private boolean isScrollable = true;
    private ArrayMap<String, Long> mRefToViewType;
    private SparseArray<ArrayList<WXComponent>> mViewTypes;
    private WXRecyclerViewOnScrollListener mViewOnScrollListener = new WXRecyclerViewOnScrollListener(this);
  
    private static final int MAX_VIEWTYPE_ALLOW_CACHE = 9;
    private static boolean mAllowCacheViewHolder = true;
    private static boolean mDownForBidCacheViewHolder = false;
  
  
    protected int mLayoutType = WXRecyclerView.TYPE_LINEAR_LAYOUT;
    protected int mColumnCount = 1;
    protected float mColumnGap = 0;
    protected float mColumnWidth = 0;
    protected float mLeftGap = 0;
    protected float mRightGap = 0;
  
    private int mOffsetAccuracy = 10;
    private Point mLastReport = new Point(-1, -1);
    private boolean mHasAddScrollEvent = false;
  
    private RecyclerView.ItemAnimator mItemAnimator;
  
    private DragHelper mDragHelper;
  
    /**
     * exclude cell when dragging(attributes for cell)
     */
    private static final String EXCLUDED = "dragExcluded";
  
    /**
     * the type to trigger drag-drop
     */
    private static final String DRAG_TRIGGER_TYPE = "dragTriggerType";
  
    private static final String DEFAULT_TRIGGER_TYPE = DragTriggerType.LONG_PRESS;
    private static final boolean DEFAULT_EXCLUDED = false;
  
    private static final String DRAG_ANCHOR = "dragAnchor";
  
    /**
     * gesture type which can trigger drag&drop
     */
    interface DragTriggerType {
      String PAN = "pan";
      String LONG_PRESS = "longpress";
    }
  
    private String mTriggerType;
  
    /**
     * Map for storing component that is sticky.
     **/
    private Map<String, Map<String, WXComponent>> mStickyMap = new HashMap<>();
    private WXStickyHelper stickyHelper;
  
    /**
     * scroll start and scroll end event
     * */
    private ScrollStartEndHelper mScrollStartEndHelper;
  
    /**
     * keep positon
     * */
    private  WXComponent keepPositionCell = null;
    private  Runnable keepPositionCellRunnable = null;
    private  long keepPositionLayoutDelay = 150;
  
  
    public BasicListComponent(
        WXSDKInstance instance, WXVContainer parent, BasicComponentData basicComponentData) {
      super(instance, parent, basicComponentData);
      stickyHelper = new WXStickyHelper(this);
    }
  
    @SuppressLint("RtlHardcoded")
    @Override
    public void setMarginsSupportRTL(ViewGroup.MarginLayoutParams lp, int left, int top, int right, int bottom) {
      if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.JELLY_BEAN_MR1) {
        lp.setMargins(left, top, right, bottom);
        lp.setMarginStart(left);
        lp.setMarginEnd(right);
      } else {
        if (lp instanceof FrameLayout.LayoutParams) {
          FrameLayout.LayoutParams lp_frameLayout = (FrameLayout.LayoutParams) lp;
          if (this.isLayoutRTL()) {
            lp_frameLayout.gravity = Gravity.RIGHT | Gravity.TOP;
            lp.setMargins(right, top, left, bottom);
          } else {
            lp_frameLayout.gravity = Gravity.LEFT | Gravity.TOP;
            lp.setMargins(left, top, right, bottom);
          }
        } else {
          lp.setMargins(left, top, right, bottom);
        }
      }
    }
  
    @Override
    public void setLayout(WXComponent component) {
      if (component.getHostView() != null) {
        int layoutDirection = component.isLayoutRTL() ? ViewCompat.LAYOUT_DIRECTION_RTL : ViewCompat.LAYOUT_DIRECTION_LTR;
        ViewCompat.setLayoutDirection(component.getHostView(), layoutDirection);
      }
      super.setLayout(component);
    }
  
    @Override
    protected void onHostViewInitialized(T host) {
      super.onHostViewInitialized(host);
  
      WXRecyclerView recyclerView = host.getInnerView();
      if (recyclerView == null || recyclerView.getAdapter() == null) {
        WXLogUtils.e(TAG, "RecyclerView is not found or Adapter is not bound");
        return;
      }
      if(WXUtils.getBoolean(getAttrs().get("prefetchGapDisable"), false)){
        if(recyclerView.getLayoutManager() != null){
          recyclerView.getLayoutManager().setItemPrefetchEnabled(false);
        }
      }
  
      if (mChildren == null) {
        WXLogUtils.e(TAG, "children is null");
        return;
      }
  
      mDragHelper = new DefaultDragHelper(mChildren, recyclerView, new EventTrigger() {
        @Override
        public void triggerEvent(String type, Map<String, Object> args) {
          fireEvent(type, args);
        }
      });
  
      mTriggerType = getTriggerType(this);
    }
  
    /**
     * Measure the size of the recyclerView.
     *
     * @param width  the expected width
     * @param height the expected height
     * @return the result of measurement
     */
    @Override
    protected MeasureOutput measure(int width, int height) {
      int screenH = WXViewUtils.getScreenHeight(getInstanceId());
      int weexH = WXViewUtils.getWeexHeight(getInstanceId());
      int outHeight = height > (weexH >= screenH ? screenH : weexH) ? weexH - getAbsoluteY() : height;
      return super.measure(width, outHeight);
    }
  
    public int getOrientation() {
      return Constants.Orientation.VERTICAL;
    }
  
    @Override
    public void destroy() {
      if(mAppearChangeRunnable != null &&  getHostView() != null) {
        getHostView().removeCallbacks(mAppearChangeRunnable);
        mAppearChangeRunnable = null;
      }
      super.destroy();
      if (mStickyMap != null)
        mStickyMap.clear();
      if (mViewTypes != null)
        mViewTypes.clear();
      if (mRefToViewType != null)
        mRefToViewType.clear();
  
    }
  
    @Override
    public ViewGroup.LayoutParams getChildLayoutParams(WXComponent child, View hostView, int width, int height, int left, int right, int top, int bottom) {
      ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) hostView.getLayoutParams();
      if (child instanceof WXBaseRefresh && params == null) {
        params = new LinearLayout.LayoutParams(width, height);
      } else if (params == null) {
        params = new RecyclerView.LayoutParams(width, height);
      } else {
        params.width = width;
        params.height = height;
  
        this.setMarginsSupportRTL(params, left, 0, right, 0);
      }
      return params;
    }
  
    abstract T generateListView(Context context, int orientation);
  
    @Override
    protected T initComponentHostView(@NonNull Context context) {
      T bounceRecyclerView = generateListView(context, getOrientation());
  
      String transforms = getAttrByKey(TRANSFORM);
      if (transforms != null) {
        bounceRecyclerView.getInnerView().addItemDecoration(RecyclerTransform.parseTransforms(getOrientation(), transforms));
      }
      if(getAttrs().get(Constants.Name.KEEP_POSITION_LAYOUT_DELAY) != null){
        keepPositionLayoutDelay = WXUtils.getNumberInt(getAttrs().get(Constants.Name.KEEP_POSITION_LAYOUT_DELAY), (int)keepPositionLayoutDelay);
      }
      if(getAttrs().get("appearActionDelay") != null){
        mAppearChangeRunnableDelay =  WXUtils.getNumberInt(getAttrs().get("appearActionDelay"), (int) mAppearChangeRunnableDelay);
      }
  
      mItemAnimator=bounceRecyclerView.getInnerView().getItemAnimator();
  
      RecyclerViewBaseAdapter recyclerViewBaseAdapter = new RecyclerViewBaseAdapter<>(this);
      recyclerViewBaseAdapter.setHasStableIds(true);
      bounceRecyclerView.setRecyclerViewBaseAdapter(recyclerViewBaseAdapter);
      bounceRecyclerView.setOverScrollMode(View.OVER_SCROLL_NEVER);
      bounceRecyclerView.getInnerView().addOnScrollListener(mViewOnScrollListener);
      if(getAttrs().get(Constants.Name.HAS_FIXED_SIZE) != null){
        boolean hasFixedSize = WXUtils.getBoolean(getAttrs().get(Constants.Name.HAS_FIXED_SIZE), false);
        bounceRecyclerView.getInnerView().setHasFixedSize(hasFixedSize);
      }
  
      bounceRecyclerView.getInnerView().addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
          super.onScrollStateChanged(recyclerView, newState);
          getScrollStartEndHelper().onScrollStateChanged(newState);
          List<OnWXScrollListener> listeners = getInstance().getWXScrollListeners();
          int size;
          OnWXScrollListener listener;
          if (listeners != null && (size = listeners.size()) > 0) {
            for (int i=0; i<size; ++i) {
              if(i >= listeners.size()){
                break;
              }
              listener = listeners.get(i);
              if (listener != null) {
                View topView = recyclerView.getChildAt(0);
                if (topView != null) {
                  int y = topView.getTop();
                  listener.onScrollStateChanged(recyclerView, 0, y, newState);
                }
              }
            }
          }
        }
  
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
          super.onScrolled(recyclerView, dx, dy);
          List<OnWXScrollListener> listeners = getInstance().getWXScrollListeners();
          if (listeners != null && listeners.size() > 0) {
            try {
              for (OnWXScrollListener listener : listeners) {
                if (listener != null) {
                  if (listener instanceof ICheckBindingScroller) {
                    if (((ICheckBindingScroller) listener).isNeedScroller(getRef(), null)) {
                      listener.onScrolled(recyclerView, dx, dy);
                    }
                  } else {
                    listener.onScrolled(recyclerView, dx, dy);
                  }
                }
              }
            } catch (Exception e) {
              e.printStackTrace();
            }
          }
        }
      });
  
      bounceRecyclerView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
        @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
        @Override
        public void onGlobalLayout() {
          T view;
          if ((view = getHostView()) == null)
            return;
          mViewOnScrollListener.onScrolled(view.getInnerView(), 0, 0);
          if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
            view.getViewTreeObserver().removeOnGlobalLayoutListener(this);
          } else {
            view.getViewTreeObserver().removeGlobalOnLayoutListener(this);
          }
        }
      });
      return bounceRecyclerView;
    }
  
    @Override
    public void bindStickStyle(WXComponent component) {
      stickyHelper.bindStickStyle(component, mStickyMap);
    }
  
    @Override
    public void unbindStickStyle(WXComponent component) {
      stickyHelper.unbindStickStyle(component, mStickyMap);
      WXHeader cell = (WXHeader) findTypeParent(component, WXHeader.class);
      if(cell != null && getHostView() != null) {
        getHostView().notifyStickyRemove(cell);
      }
    }
  
    private
    @Nullable
    WXComponent findDirectListChild(WXComponent comp) {
      WXComponent parent;
      if (comp == null || (parent = comp.getParent()) == null) {
        return null;
      }
  
      if (parent instanceof BasicListComponent) {
        return comp;
      }
  
      return findDirectListChild(parent);
    }
  
    @Override
    protected boolean setProperty(String key, Object param) {
      switch (key) {
        case LOADMOREOFFSET:
          return true;
        case Constants.Name.SCROLLABLE:
          boolean scrollable = WXUtils.getBoolean(param, true);
          setScrollable(scrollable);
          return true;
        case Constants.Name.OFFSET_ACCURACY:
          int accuracy = WXUtils.getInteger(param, 10);
          setOffsetAccuracy(accuracy);
          return true;
        case Constants.Name.DRAGGABLE:
          boolean draggable = WXUtils.getBoolean(param,false);
          setDraggable(draggable);
          return true;
        case Constants.Name.SHOW_SCROLLBAR:
          Boolean result = WXUtils.getBoolean(param,null);
          if (result != null)
            setShowScrollbar(result);
          return true;
      }
      return super.setProperty(key, param);
    }
  
    @WXComponentProp(name = Constants.Name.SCROLLABLE)
    public void setScrollable(boolean scrollable) {
      this.isScrollable = scrollable;
      WXRecyclerView inner = getHostView().getInnerView();
      if(inner != null) {
        inner.setScrollable(scrollable);
      }
    }
  
    @WXComponentProp(name = Constants.Name.OFFSET_ACCURACY)
    public void setOffsetAccuracy(int accuracy) {
      float real = WXViewUtils.getRealPxByWidth(accuracy, getInstance().getInstanceViewPortWidth());
      this.mOffsetAccuracy = (int) real;
    }
  
    @WXComponentProp(name = Constants.Name.DRAGGABLE)
    public void setDraggable(boolean isDraggable) {
      if (mDragHelper != null) {
        mDragHelper.setDraggable(isDraggable);
      }
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d("set draggable : " + isDraggable);
      }
    }
  
    @WXComponentProp(name = Constants.Name.SHOW_SCROLLBAR)
    public void setShowScrollbar(boolean show) {
      if(getHostView() == null || getHostView().getInnerView() == null){
        return;
      }
      if (getOrientation() == Constants.Orientation.VERTICAL) {
        getHostView().getInnerView().setVerticalScrollBarEnabled(show);
      } else {
        getHostView().getInnerView().setHorizontalScrollBarEnabled(show);
      }
    }
  
    @Override
    public boolean isScrollable() {
      return isScrollable;
    }
  
  
    private void setAppearanceWatch(WXComponent component, int event, boolean enable) {
      AppearanceHelper item = mAppearComponents.get(component.getRef());
      if (item != null) {
        item.setWatchEvent(event, enable);
      } else if (!enable) {
        //Do nothing if disable target not exist.
      } else {
        WXComponent dChild = findDirectListChild(component);
        int index = mChildren.indexOf(dChild);
        if (index != -1) {
          item = new AppearanceHelper(component, index);
          item.setWatchEvent(event, true);
          mAppearComponents.put(component.getRef(), item);
        }
      }
    }
  
    @Override
    public void bindAppearEvent(WXComponent component) {
      setAppearanceWatch(component, AppearanceHelper.APPEAR, true);
      if(mAppearChangeRunnable == null){
        mAppearChangeRunnable =  new Runnable() {
          @Override
          public void run() {
            if(mAppearChangeRunnable != null) {
              notifyAppearStateChange(0, 0, 0, 0);
            }
          }
        };
      }
      if (getHostView() != null) {
        getHostView().removeCallbacks(mAppearChangeRunnable);
        getHostView().postDelayed(mAppearChangeRunnable, mAppearChangeRunnableDelay);
      }
    }
  
    @Override
    public void bindDisappearEvent(WXComponent component) {
      setAppearanceWatch(component, AppearanceHelper.DISAPPEAR, true);
    }
  
    @Override
    public void unbindAppearEvent(WXComponent component) {
      setAppearanceWatch(component, AppearanceHelper.APPEAR, false);
    }
  
    @Override
    public void unbindDisappearEvent(WXComponent component) {
      setAppearanceWatch(component, AppearanceHelper.DISAPPEAR, false);
    }
  
    @Override
    public void scrollTo(WXComponent component, Map<String, Object> options) {
      float offsetFloat = 0;
      boolean smooth = true;
  
      if (options != null) {
        String offsetStr = options.get(Constants.Name.OFFSET) == null ? "0" : options.get(Constants.Name.OFFSET).toString();
        smooth = WXUtils.getBoolean(options.get(Constants.Name.ANIMATED), true);
        if (offsetStr != null) {
          try {
            offsetFloat = WXViewUtils.getRealPxByWidth(Float.parseFloat(offsetStr), getInstance().getInstanceViewPortWidth());
          }catch (Exception e ){
            WXLogUtils.e("Float parseFloat error :"+e.getMessage());
          }
        }
      }
  
      final int offset = (int) offsetFloat;
  
      T bounceRecyclerView = getHostView();
      if (bounceRecyclerView == null) {
        return;
      }
  
      WXComponent parent = component;
      WXCell cell = null;
      while (parent != null) {
        if (parent instanceof WXCell) {
          cell = (WXCell) parent;
          break;
        }
        parent = parent.getParent();
      }
  
      if (cell != null) {
        final int pos = mChildren.indexOf(cell);
        if (pos == -1) {
          //Invalid position
          return;
        }
        final WXRecyclerView view = bounceRecyclerView.getInnerView();
        view.scrollTo(smooth, pos, offset, getOrientation());
      }
    }
  
    @Override
    public void onBeforeScroll(int dx, int dy) {
      T bounceRecyclerView = getHostView();
      if (mStickyMap == null || bounceRecyclerView == null) {
        return;
      }
      Map<String, WXComponent> stickyMap = mStickyMap.get(getRef());
      if (stickyMap == null) {
        return;
      }
      Iterator<Map.Entry<String, WXComponent>> iterator = stickyMap.entrySet().iterator();
      Map.Entry<String, WXComponent> entry;
      WXComponent stickyComponent;
      int currentStickyPos = -1;
      while (iterator.hasNext()) {
        entry = iterator.next();
        stickyComponent = entry.getValue();
  
        if (stickyComponent != null && stickyComponent instanceof WXCell) {
  
          WXCell cell = (WXCell) stickyComponent;
          if (cell.getHostView() == null) {
            return;
          }
  
          int[] location = new int[2];
          stickyComponent.getHostView().getLocationOnScreen(location);
          int[] parentLocation = new int[2];
          stickyComponent.getParentScroller().getView().getLocationOnScreen(parentLocation);
          int top = location[1] - parentLocation[1];
  
  
          RecyclerView.LayoutManager layoutManager;
          boolean beforeFirstVisibleItem = false;
          boolean removeOldSticky = false;
          layoutManager = getHostView().getInnerView().getLayoutManager();
          if (layoutManager instanceof LinearLayoutManager || layoutManager instanceof GridLayoutManager) {
            int firstVisiblePosition = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
            int lastVisiblePosition = ((LinearLayoutManager) layoutManager).findLastVisibleItemPosition();
            int pos = mChildren.indexOf(cell);
            cell.setScrollPositon(pos);
            if (pos <= firstVisiblePosition
                    || (cell.getStickyOffset() > 0 && firstVisiblePosition < pos && pos <= lastVisiblePosition  &&
                    top <= cell.getStickyOffset())) {
              beforeFirstVisibleItem = true;
              if(pos > currentStickyPos) {
                currentStickyPos = pos;
              }
            }else{
              removeOldSticky = true;
            }
          } else if(layoutManager instanceof StaggeredGridLayoutManager){
            int [] firstItems= new int[3];
            int firstVisiblePosition = ((StaggeredGridLayoutManager) layoutManager).findFirstVisibleItemPositions(firstItems)[0];
            int lastVisiblePosition = ((StaggeredGridLayoutManager)  layoutManager).findLastVisibleItemPositions(firstItems)[0];
            int pos = mChildren.indexOf(cell);
  
            if (pos <= firstVisiblePosition || (cell.getStickyOffset() > 0 && firstVisiblePosition < pos && pos <= lastVisiblePosition  &&
                    top <= cell.getStickyOffset())) {
              beforeFirstVisibleItem = true;
              if(pos > currentStickyPos) {
                currentStickyPos = pos;
              }
            }else{
              removeOldSticky = true;
            }
          }
  
  
          boolean showSticky = beforeFirstVisibleItem && cell.getLocationFromStart() >= 0 && top <= cell.getStickyOffset() && dy >= 0;
          boolean removeSticky = cell.getLocationFromStart() <= cell.getStickyOffset() && top > cell.getStickyOffset() && dy <= 0;
          if (showSticky) {
            bounceRecyclerView.notifyStickyShow(cell);
          } else if (removeSticky || removeOldSticky) {
            bounceRecyclerView.notifyStickyRemove(cell);
          }
          cell.setLocationFromStart(top);
        }
      }
  
      if(currentStickyPos >= 0){
        bounceRecyclerView.updateStickyView(currentStickyPos);
      }else{
        if(bounceRecyclerView instanceof BounceRecyclerView){
          ((BounceRecyclerView) bounceRecyclerView).getStickyHeaderHelper().clearStickyHeaders();
        }
      }
    }
  
    @Override
    public int getScrollY() {
      T bounceRecyclerView = getHostView();
      return bounceRecyclerView == null ? 0 : bounceRecyclerView.getInnerView().getScrollY();
    }
  
    @Override
    public int getScrollX() {
      T bounceRecyclerView = getHostView();
      return bounceRecyclerView == null ? 0 : bounceRecyclerView.getInnerView().getScrollX();
    }
  
    /**
     * Append a child component to the end of list. This will not refresh the underlying
     * view immediately. The message of index of the inserted child is given to the adapter, and the
     * adapter will determine when to refresh. The default implementation of adapter will push the
     * message into a message and refresh the view in a period of time.
     *
     * @param child the inserted child
     */
    @Override
    public void addChild(WXComponent child) {
      addChild(child, -1);
    }
  
    @Override
    protected int getChildrenLayoutTopOffset() {
      return 0;
    }
  
    /**
     * @param child the inserted child
     * @param index the index of the child to be inserted.
     * @see #addChild(WXComponent)
     */
    @Override
    public void addChild(WXComponent child, int index) {
      super.addChild(child, index);
      if (child == null || index < -1) {
        return;
      }
      int count = mChildren.size();
      index = index >= count ? -1 : index;
      bindViewType(child);
  
      int adapterPosition = index == -1 ? mChildren.size() - 1 : index;
      final T view = getHostView();
      if (view != null) {
        boolean isAddAnimation = false;
        if (getBasicComponentData() != null) {
          Object attr = getAttrs().get(Constants.Name.INSERT_CELL_ANIMATION);
          if (Constants.Value.DEFAULT.equals(attr)) {
            isAddAnimation = true;
          }
        }
        if (isAddAnimation) {
          view.getInnerView().setItemAnimator(mItemAnimator);
        } else {
          view.getInnerView().setItemAnimator(null);
        }
        boolean isKeepScrollPosition =  false;
        if (child.getBasicComponentData() != null) {
          Object attr = child.getAttrs().get(Constants.Name.KEEP_SCROLL_POSITION);
          if (WXUtils.getBoolean(attr, false) && index <= getChildCount() && index>-1) {
            isKeepScrollPosition = true;
          }
        }
        if (isKeepScrollPosition) {
          if(view.getInnerView().getLayoutManager() instanceof  LinearLayoutManager){
            if(keepPositionCell == null){
              int last=((LinearLayoutManager)view.getInnerView().getLayoutManager()).findLastCompletelyVisibleItemPosition();
              ListBaseViewHolder holder = (ListBaseViewHolder) view.getInnerView().findViewHolderForAdapterPosition(last);
              if(holder != null){
                keepPositionCell = holder.getComponent();
              }
              if(keepPositionCell != null) {
                if(!view.getInnerView().isLayoutFrozen()){ //frozen, prevent layout when scroll
                  view.getInnerView().setLayoutFrozen(true);
                }
                if(keepPositionCellRunnable != null){
                  view.removeCallbacks(keepPositionCellRunnable);
                }
                keepPositionCellRunnable = new Runnable() {
                  @Override
                  public void run() {
                    if(keepPositionCell != null){
                      int keepPosition = indexOf(keepPositionCell);
                      int offset = 0;
                      if(keepPositionCell.getHostView() != null){
                        offset = keepPositionCell.getHostView().getTop();
                      }
                      if(offset > 0) {
                        ((LinearLayoutManager) view.getInnerView().getLayoutManager()).scrollToPositionWithOffset(keepPosition, offset);
                      }else{
                        view.getInnerView().getLayoutManager().scrollToPosition(keepPosition);
  
                      }
                      view.getInnerView().setLayoutFrozen(false);
                      keepPositionCell = null;
                      keepPositionCellRunnable = null;
                    }
                  }
                };
              }
            }
            if(keepPositionCellRunnable == null){
              view.getInnerView().scrollToPosition(((LinearLayoutManager)view.getInnerView().getLayoutManager()).findLastVisibleItemPosition());
            }
          }
          view.getRecyclerViewBaseAdapter().notifyItemInserted(adapterPosition);
          if(keepPositionCellRunnable != null){
            view.removeCallbacks(keepPositionCellRunnable);
            view.postDelayed(keepPositionCellRunnable, keepPositionLayoutDelay);
          }
        } else {
          view.getRecyclerViewBaseAdapter().notifyItemChanged(adapterPosition);
        }
      }
      relocateAppearanceHelper();
    }
  
    private void relocateAppearanceHelper() {
      Iterator<Map.Entry<String, AppearanceHelper>> iterator = mAppearComponents.entrySet().iterator();
      while (iterator.hasNext()) {
        Map.Entry<String, AppearanceHelper> item = iterator.next();
        AppearanceHelper value = item.getValue();
        WXComponent dChild = findDirectListChild(value.getAwareChild());
        int index = mChildren.indexOf(dChild);
        value.setCellPosition(index);
      }
    }
  
  
    /**
     * RecyclerView manage its children in a way that different from {@link WXVContainer}. Therefore,
     * {@link WXVContainer#addSubView(View, int)} is an empty implementation in {@link
     * WXRecyclerView}
     */
    @Override
    public void addSubView(View child, int index) {
  
    }
  
    /**
     * Remove the child from list. This method will use {@link
     * java.util.List#indexOf(Object)} to retrieve the component to be deleted. Like {@link
     * #addChild(WXComponent)}, this method will not refresh the view immediately, the adapter will
     * decide when to refresh.
     *
     * @param child the child to be removed
     */
    @Override
    public void remove(WXComponent child, boolean destroy) {
      int index = mChildren.indexOf(child);
      if (destroy) {
        child.detachViewAndClearPreInfo();
      }
      unBindViewType(child);
  
      T view = getHostView();
      if (view == null) {
        return;
      }
  
      boolean isRemoveAnimation = false;
      Object attr = child.getAttrs().get(Constants.Name.DELETE_CELL_ANIMATION);
      if (Constants.Value.DEFAULT.equals(attr)) {
        isRemoveAnimation = true;
      }
      if (isRemoveAnimation) {
        view.getInnerView().setItemAnimator(mItemAnimator);
      } else {
        view.getInnerView().setItemAnimator(null);
      }
  
      view.getRecyclerViewBaseAdapter().notifyItemRemoved(index);
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d(TAG, "removeChild child at " + index);
      }
      super.remove(child, destroy);
    }
  
  
  
    @Override
    public void computeVisiblePointInViewCoordinate(PointF pointF) {
      RecyclerView view = getHostView().getInnerView();
      pointF.set(view.computeHorizontalScrollOffset(), view.computeVerticalScrollOffset());
    }
  
    /**
     * Recycle viewHolder and its underlying view. This may because the view is removed or reused.
     * Either case, this method will be called.
     *
     * @param holder The view holder to be recycled.
     */
    @Override
    public void onViewRecycled(ListBaseViewHolder holder) {
      long begin = System.currentTimeMillis();
  
      holder.setComponentUsing(false);
      if (holder != null
              && holder.canRecycled()
              && holder.getComponent() != null
              && !holder.getComponent().isUsing()) {
        holder.recycled();
  
      } else {
        WXLogUtils.w(TAG, "this holder can not be allowed to  recycled");
      }
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d(TAG, "Recycle holder " + (System.currentTimeMillis() - begin) + "  Thread:" + Thread.currentThread().getName());
      }
    }
  
    /**
     * Bind the component of the position to the holder. Then flush the view.
     *
     * @param holder   viewHolder, which holds reference to the view
     * @param position position of component in list
     */
    @Override
    public void onBindViewHolder(final ListBaseViewHolder holder, int position) {
      if (holder == null) return;
      holder.setComponentUsing(true);
      WXComponent component = getChild(position);
      if (component == null
              || (component instanceof WXRefresh)
              || (component instanceof WXLoading)
              || (component.isFixed())
              ) {
        if (WXEnvironment.isApkDebugable()) {
          WXLogUtils.d(TAG, "Bind WXRefresh & WXLoading " + holder);
        }
        if(component instanceof  WXBaseRefresh
                && holder.getView() != null
                && (component.getAttrs().get("holderBackground") != null)){
          Object holderBackground = component.getAttrs().get("holderBackground");
          int color = WXResourceUtils.getColor(holderBackground.toString(), Color.WHITE);
          holder.getView().setBackgroundColor(color);
          holder.getView().setVisibility(View.VISIBLE);
          holder.getView().postInvalidate();
        }
        return;
      }
  
      if (holder.getComponent() != null && holder.getComponent() instanceof WXCell) {
        if(holder.isRecycled()) {
          holder.bindData(component);
          component.onRenderFinish(STATE_UI_FINISH);
        }
        if (mDragHelper == null || !mDragHelper.isDraggable()) {
          return;
        }
        mTriggerType = (mTriggerType == null) ? DEFAULT_TRIGGER_TYPE : mTriggerType;
  
        WXCell cell = (WXCell) holder.getComponent();
        boolean isExcluded = DEFAULT_EXCLUDED;
        WXAttr cellAttrs = cell.getAttrs();
        isExcluded = WXUtils.getBoolean(cellAttrs.get(EXCLUDED), DEFAULT_EXCLUDED);
  
        mDragHelper.setDragExcluded(holder, isExcluded);
  
        //NOTICE: event maybe consumed by other views
        if (DragTriggerType.PAN.equals(mTriggerType)) {
          mDragHelper.setLongPressDragEnabled(false);
  
          WXComponent anchorComponent = findComponentByAnchorName(cell, DRAG_ANCHOR);
  
          if (anchorComponent != null && anchorComponent.getHostView() != null && !isExcluded) {
            View anchor = anchorComponent.getHostView();
            anchor.setOnTouchListener(new View.OnTouchListener() {
              @SuppressLint("ClickableViewAccessibility")
              @Override
              public boolean onTouch(View v, MotionEvent event) {
                if (MotionEventCompat.getActionMasked(event) == MotionEvent.ACTION_DOWN) {
                  mDragHelper.startDrag(holder);
                }
                return true;
              }
            });
          } else {
            if (WXEnvironment.isApkDebugable()) {
              if(!isExcluded) {
                WXLogUtils.e(TAG, "[error] onBindViewHolder: the anchor component or view is not found");
              } else {
                WXLogUtils.d(TAG, "onBindViewHolder: position "+ position + " is drag excluded");
              }
            }
          }
  
        } else if (DragTriggerType.LONG_PRESS.equals(mTriggerType)) {
          mDragHelper.setLongPressDragEnabled(true);
        }
      }
  
    }
  
    protected void markComponentUsable(){
      for (WXComponent component : mChildren){
        component.setUsing(false);
      }
    }
    /**
     * Create an instance of {@link ListBaseViewHolder} for the given viewType (not for the given
     * index). This  markComponentUsable();method will look up for the first component that fits the viewType requirement and
     * doesn't be used. Then create the certain type of view, detach the view f[rom the component.
     *
     * @param parent   the ViewGroup into which the new view will be inserted
     * @param viewType the type of the new view
     * @return the created view holder.
     */
    @Override
    public ListBaseViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
      if (mChildren != null) {
        if (mViewTypes == null)
          return createVHForFakeComponent(viewType);
        ArrayList<WXComponent> mTypes = mViewTypes.get(viewType);
        checkRecycledViewPool(viewType);
        if (mTypes == null)
          return createVHForFakeComponent(viewType);
  
        for (int i = 0; i < mTypes.size(); i++) {
          WXComponent component = mTypes.get(i);
          if (component == null
              || component.isUsing()) {
            continue;
          }
          if (component.isFixed()) {
            return createVHForFakeComponent(viewType);
          } else {
            if (component instanceof WXCell) {
              if (component.getRealView() != null) {
                return new ListBaseViewHolder(component, viewType);
              } else {
                component.lazy(false);
                component.createView();
                component.applyLayoutAndEvent(component);
                return new ListBaseViewHolder(component, viewType, true);
              }
            } else if (component instanceof WXBaseRefresh) {
              return createVHForRefreshComponent(viewType);
            } else {
              WXLogUtils.e(TAG, "List cannot include element except cell、header、fixed、refresh and loading");
              return createVHForFakeComponent(viewType);
            }
          }
        }
      }
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.e(TAG, "Cannot find request viewType: " + viewType);
      }
      return createVHForFakeComponent(viewType);
    }
  
    /**
     * Forbid ViewHolder cache if viewType > MAX_VIEWTYPE_ALLOW_CACHE
     *
     * @param viewType
     */
    private void checkRecycledViewPool(int viewType) {
      try {
        if (mViewTypes.size() > MAX_VIEWTYPE_ALLOW_CACHE)
          mAllowCacheViewHolder = false;
  
        if (mDownForBidCacheViewHolder)
          if (getHostView() != null && getHostView().getInnerView() != null)
            getHostView().getInnerView().getRecycledViewPool().setMaxRecycledViews(viewType, 0);
  
        if (!mDownForBidCacheViewHolder) {
          if (!mAllowCacheViewHolder) {
            if (getHostView() != null && getHostView().getInnerView() != null) {
              for (int i = 0; i < mViewTypes.size(); i++) {
                getHostView().getInnerView().getRecycledViewPool().setMaxRecycledViews(mViewTypes.keyAt(i), 0);
              }
              mDownForBidCacheViewHolder = true;
            }
          }
        }
      } catch (Exception e) {
        WXLogUtils.e(TAG, "Clear recycledViewPool error!");
      }
    }
  
    /**
     * Return the child component type. The type is defined by scopeValue in .we file.
     *
     * @param position the position of the child component.
     * @return the type of certain component.
     */
    @Override
    public int getItemViewType(int position) {
      return generateViewType(getChild(position));
    }
  
    @Nullable
    private WXComponent findComponentByAnchorName(@NonNull WXComponent root, @NonNull String anchorName) {
      long start = 0;
      if (WXEnvironment.isApkDebugable()) {
        start = System.currentTimeMillis();
      }
  
      Deque<WXComponent> deque = new ArrayDeque<>();
      deque.add(root);
      while (!deque.isEmpty()) {
        WXComponent curComponent = deque.removeFirst();
        if (curComponent != null) {
          String isAnchorSet = WXUtils.getString(curComponent.getAttrs().get(anchorName), null);
  
          //hit
          if (isAnchorSet != null && isAnchorSet.equals("true")) {
            if (WXEnvironment.isApkDebugable()) {
              WXLogUtils.d("dragPerf", "findComponentByAnchorName time: " + (System.currentTimeMillis() - start) + "ms");
            }
            return curComponent;
          }
        }
        if (curComponent instanceof WXVContainer) {
          WXVContainer container = (WXVContainer) curComponent;
          for (int i = 0, len = container.childCount(); i < len; i++) {
            WXComponent child = container.getChild(i);
            deque.add(child);
          }
        }
      }
  
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d("dragPerf", "findComponentByAnchorName elapsed time: " + (System.currentTimeMillis() - start) + "ms");
      }
      return null;
  
    }
  
    private String getTriggerType(@Nullable WXComponent component) {
      String triggerType = DEFAULT_TRIGGER_TYPE;
      if (component == null) {
        return triggerType;
      }
      triggerType = WXUtils.getString(component.getAttrs().get(DRAG_TRIGGER_TYPE), DEFAULT_TRIGGER_TYPE);
      if (!DragTriggerType.LONG_PRESS.equals(triggerType) && !DragTriggerType.PAN.equals(triggerType)) {
        triggerType = DEFAULT_TRIGGER_TYPE;
      }
  
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d(TAG, "trigger type is " + triggerType);
      }
  
      return triggerType;
    }
  
  
    /**
     * ViewType will be classified into {HashMap<Integer,ArrayList<Integer>> mViewTypes}
     *
     * @param component
     */
    private void bindViewType(WXComponent component) {
      int id = generateViewType(component);
  
      if (mViewTypes == null) {
        mViewTypes = new SparseArray<>();
      }
  
      ArrayList<WXComponent> mTypes = mViewTypes.get(id);
  
      if (mTypes == null) {
        mTypes = new ArrayList<>();
        mViewTypes.put(id, mTypes);
      }
      mTypes.add(component);
    }
  
    private void unBindViewType(WXComponent component) {
      int id = generateViewType(component);
  
      if (mViewTypes == null)
        return;
      ArrayList<WXComponent> mTypes = mViewTypes.get(id);
      if (mTypes == null)
        return;
  
      mTypes.remove(component);
    }
  
    /**
     * generate viewtype by component
     *
     * @param component
     * @return
     */
    private int generateViewType(WXComponent component) {
      long id;
      try {
        id = Integer.parseInt(component.getRef());
        String type = component.getAttrs().getScope();
  
        if (!TextUtils.isEmpty(type)) {
          if (mRefToViewType == null) {
            mRefToViewType = new ArrayMap<>();
          }
          if (!mRefToViewType.containsKey(type)) {
            mRefToViewType.put(type, id);
          }
          id = mRefToViewType.get(type);
  
        }
      } catch (RuntimeException e) {
        WXLogUtils.eTag(TAG, e);
        id = RecyclerView.NO_ID;
        WXLogUtils.e(TAG, "getItemViewType: NO ID, this will crash the whole render system of WXListRecyclerView");
      }
      return (int) id;
    }
  
    /**
     * Get child component num.
     *
     * @return return the size of {@link #mChildren} if mChildren is not empty, otherwise, return 0;
     */
    @Override
    public int getItemCount() {
      return getChildCount();
    }
  
    @Override
    public boolean onFailedToRecycleView(ListBaseViewHolder holder) {
      if (WXEnvironment.isApkDebugable()) {
        WXLogUtils.d(TAG, "Failed to recycle " + holder);
      }
      return false;
    }
  
    @Override
    public long getItemId(int position) {
      long id;
      try {
        id = Long.parseLong(getChild(position).getRef());
      } catch (RuntimeException e) {
        WXLogUtils.e(TAG, WXLogUtils.getStackTrace(e));
        id = RecyclerView.NO_ID;
      }
      return id;
    }
  
    @Override
    public void onLoadMore(int offScreenY) {
      try {
        String offset = getAttrs().getLoadMoreOffset();
  
        if (TextUtils.isEmpty(offset)) {
          offset = "0";
        }
  
  
        float offsetParsed = WXViewUtils.getRealPxByWidth(WXUtils.getInt(offset),getInstance().getInstanceViewPortWidth());
  
        if (offScreenY <= offsetParsed && getEvents().contains(Constants.Event.LOADMORE)) {
          if (mListCellCount != mChildren.size()
              || mForceLoadmoreNextTime) {
            fireEvent(Constants.Event.LOADMORE);
            mListCellCount = mChildren.size();
            mForceLoadmoreNextTime = false;
          }
        }
      } catch (Exception e) {
        WXLogUtils.d(TAG + "onLoadMore :", e);
      }
    }
  
    @Override
    public void notifyAppearStateChange(int firstVisible, int lastVisible, int directionX, int directionY) {
      if(mAppearChangeRunnable != null) {
        getHostView().removeCallbacks(mAppearChangeRunnable);
        mAppearChangeRunnable = null;
      }
      //notify appear state
      Iterator<AppearanceHelper> it = mAppearComponents.values().iterator();
      String direction = directionY > 0 ? Constants.Value.DIRECTION_UP :
              directionY < 0 ? Constants.Value.DIRECTION_DOWN : null;
      if (getOrientation() == Constants.Orientation.HORIZONTAL && directionX != 0) {
        direction = directionX > 0 ? Constants.Value.DIRECTION_LEFT : Constants.Value.DIRECTION_RIGHT;
      }
  
      while (it.hasNext()) {
        AppearanceHelper item = it.next();
        WXComponent component = item.getAwareChild();
  
        if (!item.isWatch()) {
          continue;
        }
  
  
        View view = component.getHostView();
        if (view == null) {
          continue;
        }
  
        boolean outOfVisibleRange = !ViewCompat.isAttachedToWindow(view);
        boolean visible = (!outOfVisibleRange) && item.isViewVisible(true);
  
        int result = item.setAppearStatus(visible);
        if (result == AppearanceHelper.RESULT_NO_CHANGE) {
          continue;
        }
        if (WXEnvironment.isApkDebugable()) {
          WXLogUtils.d("appear", "item " + item.getCellPositionINScollable() + " result " + result);
        }
        component.notifyAppearStateChange(result == AppearanceHelper.RESULT_APPEAR ? Constants.Event.APPEAR : Constants.Event.DISAPPEAR, direction);
      }
    }
  
    @NonNull
    private ListBaseViewHolder createVHForFakeComponent(int viewType) {
      FrameLayout view = new FrameLayout(getContext());
      view.setBackgroundColor(Color.WHITE);
      view.setLayoutParams(new FrameLayout.LayoutParams(0, 0));
      return new ListBaseViewHolder(view, viewType);
    }
  
  
    private ListBaseViewHolder createVHForRefreshComponent(int viewType) {
      FrameLayout view = new FrameLayout(getContext());
      view.setLayoutParams(new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 1));
      return new ListBaseViewHolder(view, viewType);
    }
  
    @JSMethod
    public void resetLoadmore() {
      mForceLoadmoreNextTime = true;
      mListCellCount = 0;
    }
  
    @Override
    public void addEvent(String type) {
      super.addEvent(type);
      if (ScrollStartEndHelper.isScrollEvent(type)
              && getHostView() != null
              && getHostView().getInnerView() != null
              && !mHasAddScrollEvent) {
        mHasAddScrollEvent = true;
        WXRecyclerView innerView = getHostView().getInnerView();
        innerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
          private int offsetXCorrection, offsetYCorrection;
          private boolean mFirstEvent = true;
  
          @Override
          public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            super.onScrolled(recyclerView, dx, dy);
  //          WXLogUtils.e("SCROLL", dx + ", " + dy + ", " + recyclerView.computeHorizontalScrollRange()
  //          + ", " + recyclerView.computeVerticalScrollRange()
  //          + ", " + recyclerView.computeHorizontalScrollOffset()
  //          + ", " + recyclerView.computeVerticalScrollOffset());
  
            int offsetX = recyclerView.computeHorizontalScrollOffset();
            int offsetY = recyclerView.computeVerticalScrollOffset();
  
            if (dx == 0 && dy == 0) {
              offsetXCorrection = offsetX;
              offsetYCorrection = offsetY;
              offsetX = 0;
              offsetY = 0;
            } else {
              offsetX = offsetX - offsetXCorrection;
              offsetY = offsetY - offsetYCorrection;
            }
            getScrollStartEndHelper().onScrolled(offsetX, offsetY);
            if(!getEvents().contains(Constants.Event.SCROLL)){
              return;
            }
            if (mFirstEvent) {
              //skip first event
              mFirstEvent = false;
              return;
            }
  
            RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
            if (!layoutManager.canScrollVertically()) {
              return;
            }
  
            if (shouldReport(offsetX, offsetY)) {
              fireScrollEvent(recyclerView, offsetX, offsetY);
            }
          }
        });
      }
    }
  
    private void fireScrollEvent(RecyclerView recyclerView, int offsetX, int offsetY) {
      fireEvent(Constants.Event.SCROLL, getScrollEvent(recyclerView, offsetX, offsetY));
    }
  
    public Map<String, Object> getScrollEvent(RecyclerView recyclerView, int offsetX, int offsetY){
      if(getOrientation() == Constants.Orientation.VERTICAL){
        offsetY = - calcContentOffset(recyclerView);
      }
      int contentWidth = recyclerView.getMeasuredWidth() + recyclerView.computeHorizontalScrollRange();
      int contentHeight = 0;
      for (int i = 0; i < getChildCount(); i++) {
        WXComponent child = getChild(i);
        if (child != null) {
          contentHeight += child.getLayoutHeight();
        }
      }
  
      Map<String, Object> event = new HashMap<>(3);
      Map<String, Object> contentSize = new HashMap<>(3);
      Map<String, Object> contentOffset = new HashMap<>(3);
  
      contentSize.put(Constants.Name.WIDTH, WXViewUtils.getWebPxByWidth(contentWidth, getInstance().getInstanceViewPortWidth()));
      contentSize.put(Constants.Name.HEIGHT, WXViewUtils.getWebPxByWidth(contentHeight, getInstance().getInstanceViewPortWidth()));
  
      contentOffset.put(Constants.Name.X, - WXViewUtils.getWebPxByWidth(offsetX, getInstance().getInstanceViewPortWidth()));
      contentOffset.put(Constants.Name.Y, - WXViewUtils.getWebPxByWidth(offsetY, getInstance().getInstanceViewPortWidth()));
      event.put(Constants.Name.CONTENT_SIZE, contentSize);
      event.put(Constants.Name.CONTENT_OFFSET, contentOffset);
      event.put(Constants.Name.ISDRAGGING, recyclerView.getScrollState() == RecyclerView.SCROLL_STATE_DRAGGING);
      return event;
    }
  
    private boolean shouldReport(int offsetX, int offsetY) {
      if (mLastReport.x == -1 && mLastReport.y == -1) {
        mLastReport.x = offsetX;
        mLastReport.y = offsetY;
        return true;
      }
  
      int gapX = Math.abs(mLastReport.x - offsetX);
      int gapY = Math.abs(mLastReport.y - offsetY);
  
      if (gapX >= mOffsetAccuracy || gapY >= mOffsetAccuracy) {
        mLastReport.x = offsetX;
        mLastReport.y = offsetY;
        return true;
      }
  
      return false;
    }
  
  
  
    public int calcContentOffset(RecyclerView recyclerView) {
      RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
      if (layoutManager instanceof LinearLayoutManager) {
        int firstVisibleItemPosition = ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
        if (firstVisibleItemPosition == -1) {
          return 0;
        }
  
        View firstVisibleView = layoutManager.findViewByPosition(firstVisibleItemPosition);
        int firstVisibleViewOffset = 0;
        if (firstVisibleView != null) {
          firstVisibleViewOffset = firstVisibleView.getTop();
        }
  
        int offset = 0;
        for (int i=0;i<firstVisibleItemPosition;i++) {
          WXComponent child = getChild(i);
          if (child != null) {
            offset -= child.getLayoutHeight();
          }
        }
  
        if (layoutManager instanceof GridLayoutManager) {
          int spanCount = ((GridLayoutManager) layoutManager).getSpanCount();
          offset = offset / spanCount;
        }
  
        offset += firstVisibleViewOffset;
        return offset;
      } else if (layoutManager instanceof StaggeredGridLayoutManager) {
        int spanCount = ((StaggeredGridLayoutManager) layoutManager).getSpanCount();
        int firstVisibleItemPosition = ((StaggeredGridLayoutManager) layoutManager).findFirstVisibleItemPositions(null)[0];
        if (firstVisibleItemPosition == -1) {
          return 0;
        }
  
        View firstVisibleView = layoutManager.findViewByPosition(firstVisibleItemPosition);
        int firstVisibleViewOffset = 0;
        if (firstVisibleView != null) {
          firstVisibleViewOffset = firstVisibleView.getTop();
        }
  
        int offset = 0;
        for (int i=0;i<firstVisibleItemPosition;i++) {
          WXComponent child = getChild(i);
          if (child != null) {
            offset -= child.getLayoutHeight();
          }
        }
  
        offset = offset / spanCount;
        offset += firstVisibleViewOffset;
        return offset;
      }
      //Unhandled LayoutManager type
      return -1;
    }
  
    public ScrollStartEndHelper getScrollStartEndHelper() {
      if(mScrollStartEndHelper == null){
        mScrollStartEndHelper = new ScrollStartEndHelper(this);
      }
      return mScrollStartEndHelper;
    }
  }
  