content: /*
   * Copyright (C) 2013 The Android Open Source Project
   *
   * Licensed 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 com.cjj.cartoon.custom;
  
  import android.content.Context;
  import android.database.DataSetObservable;
  import android.database.DataSetObserver;
  import android.os.Build;
  import android.util.AttributeSet;
  import android.util.Log;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.*;
  
  import java.lang.reflect.Field;
  import java.util.ArrayList;
  
  /**
   * A {@link GridView} that supports adding header rows in a
   * very similar way to {@link android.widget.ListView}.
   * See {@link GridViewWithHeaderAndFooter#addHeaderView(View, Object, boolean)}
   * See {@link GridViewWithHeaderAndFooter#addFooterView(View, Object, boolean)}
   */
  public class GridViewWithHeaderAndFooter extends GridView {
  
      public static boolean DEBUG = false;
  
      /**
       * A class that represents a fixed view in a list, for example a header at the top
       * or a footer at the bottom.
       */
      private static class FixedViewInfo {
          /**
           * The view to add to the grid
           */
          public View view;
          public ViewGroup viewContainer;
          /**
           * The data backing the view. This is returned from {@link ListAdapter#getItem(int)}.
           */
          public Object data;
          /**
           * <code>true</code> if the fixed view should be selectable in the grid
           */
          public boolean isSelectable;
      }
  
      private int mNumColumns = AUTO_FIT;
      private View mViewForMeasureRowHeight = null;
      private int mRowHeight = -1;
      private static final String LOG_TAG = "grid-view-with-header-and-footer";
  
      private ArrayList<FixedViewInfo> mHeaderViewInfos = new ArrayList<FixedViewInfo>();
      private ArrayList<FixedViewInfo> mFooterViewInfos = new ArrayList<FixedViewInfo>();
  
      private void initHeaderGridView() {
      }
  
      public GridViewWithHeaderAndFooter(Context context) {
          super(context);
          initHeaderGridView();
      }
  
      public GridViewWithHeaderAndFooter(Context context, AttributeSet attrs) {
          super(context, attrs);
          initHeaderGridView();
      }
  
      public GridViewWithHeaderAndFooter(Context context, AttributeSet attrs, int defStyle) {
          super(context, attrs, defStyle);
          initHeaderGridView();
      }
  
      @Override
      protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
          super.onMeasure(widthMeasureSpec, heightMeasureSpec);
          ListAdapter adapter = getAdapter();
          if (adapter != null && adapter instanceof HeaderViewGridAdapter) {
              ((HeaderViewGridAdapter) adapter).setNumColumns(getNumColumnsCompatible());
              ((HeaderViewGridAdapter) adapter).setRowHeight(getRowHeight());
          }
      }
  
      @Override
      public void setClipChildren(boolean clipChildren) {
          // Ignore, since the header rows depend on not being clipped
      }
  
      /**
       * Do not call this method unless you know how it works.
       *
       * @param clipChildren
       */
      public void setClipChildrenSupper(boolean clipChildren) {
          super.setClipChildren(false);
      }
  
      /**
       * Add a fixed view to appear at the top of the grid. If addHeaderView is
       * called more than once, the views will appear in the order they were
       * added. Views added using this call can take focus if they want.
       * <p/>
       * NOTE: Call this before calling setAdapter. This is so HeaderGridView can wrap
       * the supplied cursor with one that will also account for header views.
       *
       * @param v The view to add.
       */
      public void addHeaderView(View v) {
          addHeaderView(v, null, true);
      }
  
      /**
       * Add a fixed view to appear at the top of the grid. If addHeaderView is
       * called more than once, the views will appear in the order they were
       * added. Views added using this call can take focus if they want.
       * <p/>
       * NOTE: Call this before calling setAdapter. This is so HeaderGridView can wrap
       * the supplied cursor with one that will also account for header views.
       *
       * @param v            The view to add.
       * @param data         Data to associate with this view
       * @param isSelectable whether the item is selectable
       */
      public void addHeaderView(View v, Object data, boolean isSelectable) {
          ListAdapter adapter = getAdapter();
          if (adapter != null && !(adapter instanceof HeaderViewGridAdapter)) {
              throw new IllegalStateException(
                      "Cannot add header view to grid -- setAdapter has already been called.");
          }
  
          ViewGroup.LayoutParams lyp = v.getLayoutParams();
  
          FixedViewInfo info = new FixedViewInfo();
          FrameLayout fl = new FullWidthFixedViewLayout(getContext());
  
          if (lyp != null) {
              v.setLayoutParams(new FrameLayout.LayoutParams(lyp.width, lyp.height));
              fl.setLayoutParams(new AbsListView.LayoutParams(lyp.width, lyp.height));
          }
          fl.addView(v);
          info.view = v;
          info.viewContainer = fl;
          info.data = data;
          info.isSelectable = isSelectable;
          mHeaderViewInfos.add(info);
          // in the case of re-adding a header view, or adding one later on,
          // we need to notify the observer
          if (adapter != null) {
              ((HeaderViewGridAdapter) adapter).notifyDataSetChanged();
          }
      }
  
      public void addFooterView(View v) {
          addFooterView(v, null, true);
      }
  
      public void addFooterView(View v, Object data, boolean isSelectable) {
          ListAdapter mAdapter = getAdapter();
          if (mAdapter != null && !(mAdapter instanceof HeaderViewGridAdapter)) {
              throw new IllegalStateException(
                      "Cannot add header view to grid -- setAdapter has already been called.");
          }
  
          ViewGroup.LayoutParams lyp = v.getLayoutParams();
  
          FixedViewInfo info = new FixedViewInfo();
          FrameLayout fl = new FullWidthFixedViewLayout(getContext());
  
          if (lyp != null) {
              v.setLayoutParams(new FrameLayout.LayoutParams(lyp.width, lyp.height));
              fl.setLayoutParams(new AbsListView.LayoutParams(lyp.width, lyp.height));
          }
          fl.addView(v);
          info.view = v;
          info.viewContainer = fl;
          info.data = data;
          info.isSelectable = isSelectable;
          mFooterViewInfos.add(info);
  
          if (mAdapter != null) {
              ((HeaderViewGridAdapter) mAdapter).notifyDataSetChanged();
          }
      }
  
      public int getHeaderViewCount() {
          return mHeaderViewInfos.size();
      }
  
      public int getFooterViewCount() {
          return mFooterViewInfos.size();
      }
  
      /**
       * Removes a previously-added header view.
       *
       * @param v The view to remove
       * @return true if the view was removed, false if the view was not a header
       * view
       */
      public boolean removeHeaderView(View v) {
          if (mHeaderViewInfos.size() > 0) {
              boolean result = false;
              ListAdapter adapter = getAdapter();
              if (adapter != null && ((HeaderViewGridAdapter) adapter).removeHeader(v)) {
                  result = true;
              }
              removeFixedViewInfo(v, mHeaderViewInfos);
              return result;
          }
          return false;
      }
  
      /**
       * Removes a previously-added footer view.
       *
       * @param v The view to remove
       * @return true if the view was removed, false if the view was not a header
       * view
       */
      public boolean removeFooterView(View v) {
          if (mFooterViewInfos.size() > 0) {
              boolean result = false;
              ListAdapter adapter = getAdapter();
              if (adapter != null && ((HeaderViewGridAdapter) adapter).removeFooter(v)) {
                  result = true;
              }
              removeFixedViewInfo(v, mFooterViewInfos);
              return result;
          }
          return false;
      }
  
      private void removeFixedViewInfo(View v, ArrayList<FixedViewInfo> where) {
          int len = where.size();
          for (int i = 0; i < len; ++i) {
              FixedViewInfo info = where.get(i);
              if (info.view == v) {
                  where.remove(i);
                  break;
              }
          }
      }
  
      private int getNumColumnsCompatible() {
          if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
              return super.getNumColumns();
          } else {
              try {
                  Field numColumns = getClass().getSuperclass().getDeclaredField("mNumColumns");
                  numColumns.setAccessible(true);
                  return numColumns.getInt(this);
              } catch (Exception e) {
                  if (mNumColumns != -1) {
                      return mNumColumns;
                  }
                  throw new RuntimeException("Can not determine the mNumColumns for this API platform, please call setNumColumns to set it.");
              }
          }
      }
  
      private int getColumnWidthCompatible() {
          if (Build.VERSION.SDK_INT >= 16) {
              return super.getColumnWidth();
          } else {
              try {
                  Field numColumns = getClass().getSuperclass().getDeclaredField("mColumnWidth");
                  numColumns.setAccessible(true);
                  return numColumns.getInt(this);
              } catch (NoSuchFieldException e) {
                  throw new RuntimeException(e);
              } catch (IllegalAccessException e) {
                  throw new RuntimeException(e);
              }
          }
      }
  
      @Override
      protected void onDetachedFromWindow() {
          super.onDetachedFromWindow();
          mViewForMeasureRowHeight = null;
      }
  
      public void invalidateRowHeight() {
          mRowHeight = -1;
      }
  
      public int getRowHeight() {
          if (mRowHeight > 0) {
              return mRowHeight;
          }
          ListAdapter adapter = getAdapter();
          int numColumns = getNumColumnsCompatible();
  
          // adapter has not been set or has no views in it;
          if (adapter == null || adapter.getCount() <= numColumns * (mHeaderViewInfos.size() + mFooterViewInfos.size())) {
              return -1;
          }
          int mColumnWidth = getColumnWidthCompatible();
          View view = getAdapter().getView(numColumns * mHeaderViewInfos.size(), mViewForMeasureRowHeight, this);
          AbsListView.LayoutParams p = (AbsListView.LayoutParams) view.getLayoutParams();
          if (p == null) {
              p = new AbsListView.LayoutParams(-1, -2, 0);
              view.setLayoutParams(p);
          }
          int childHeightSpec = getChildMeasureSpec(
                  MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 0, p.height);
          int childWidthSpec = getChildMeasureSpec(
                  MeasureSpec.makeMeasureSpec(mColumnWidth, MeasureSpec.EXACTLY), 0, p.width);
          view.measure(childWidthSpec, childHeightSpec);
          mViewForMeasureRowHeight = view;
          mRowHeight = view.getMeasuredHeight();
          return mRowHeight;
      }
  
      public void tryToScrollToBottomSmoothly() {
          int lastPos = getAdapter().getCount() - 1;
          if (Build.VERSION.SDK_INT >= 11) {
              smoothScrollToPositionFromTop(lastPos, 0);
          } else {
              setSelection(lastPos);
          }
      }
  
      public void tryToScrollToBottomSmoothly(int duration) {
          int lastPos = getAdapter().getCount() - 1;
          if (Build.VERSION.SDK_INT >= 11) {
              smoothScrollToPositionFromTop(lastPos, 0, duration);
          } else {
              setSelection(lastPos);
          }
      }
  
      @Override
      public void setAdapter(ListAdapter adapter) {
          if (mHeaderViewInfos.size() > 0 || mFooterViewInfos.size() > 0) {
              HeaderViewGridAdapter headerViewGridAdapter = new HeaderViewGridAdapter(mHeaderViewInfos, mFooterViewInfos, adapter);
              int numColumns = getNumColumnsCompatible();
              if (numColumns > 1) {
                  headerViewGridAdapter.setNumColumns(numColumns);
              }
              headerViewGridAdapter.setRowHeight(getRowHeight());
              super.setAdapter(headerViewGridAdapter);
          } else {
              super.setAdapter(adapter);
          }
      }
  
      /**
       * full width
       */
      private class FullWidthFixedViewLayout extends FrameLayout {
  
          public FullWidthFixedViewLayout(Context context) {
              super(context);
          }
  
          @Override
          protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
              int realLeft = getPaddingLeft();
              // Try to make where it should be, from left, full width
              if (realLeft != left) {
                  offsetLeftAndRight(realLeft - left);
              }
              super.onLayout(changed, left, top, right, bottom);
          }
  
          @Override
          protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
              int targetWidth = GridViewWithHeaderAndFooter.this.getMeasuredWidth()
                      - GridViewWithHeaderAndFooter.this.getPaddingLeft()
                      - GridViewWithHeaderAndFooter.this.getPaddingRight();
              widthMeasureSpec = MeasureSpec.makeMeasureSpec(targetWidth,
                      MeasureSpec.getMode(widthMeasureSpec));
              super.onMeasure(widthMeasureSpec, heightMeasureSpec);
          }
      }
  
      @Override
      public void setNumColumns(int numColumns) {
          super.setNumColumns(numColumns);
          mNumColumns = numColumns;
          ListAdapter adapter = getAdapter();
          if (adapter != null && adapter instanceof HeaderViewGridAdapter) {
              ((HeaderViewGridAdapter) adapter).setNumColumns(numColumns);
          }
      }
  
      /**
       * ListAdapter used when a HeaderGridView has header views. This ListAdapter
       * wraps another one and also keeps track of the header views and their
       * associated data objects.
       * <p>This is intended as a base class; you will probably not need to
       * use this class directly in your own code.
       */
      private static class HeaderViewGridAdapter implements WrapperListAdapter, Filterable {
          // This is used to notify the container of updates relating to number of columns
          // or headers changing, which changes the number of placeholders needed
          private final DataSetObservable mDataSetObservable = new DataSetObservable();
          private final ListAdapter mAdapter;
          static final ArrayList<FixedViewInfo> EMPTY_INFO_LIST =
                  new ArrayList<FixedViewInfo>();
  
          // This ArrayList is assumed to NOT be null.
          ArrayList<FixedViewInfo> mHeaderViewInfos;
          ArrayList<FixedViewInfo> mFooterViewInfos;
          private int mNumColumns = 1;
          private int mRowHeight = -1;
          boolean mAreAllFixedViewsSelectable;
          private final boolean mIsFilterable;
          private boolean mCachePlaceHoldView = true;
          // From Recycle Bin or calling getView, this a question...
          private boolean mCacheFirstHeaderView = false;
  
          public HeaderViewGridAdapter(ArrayList<FixedViewInfo> headerViewInfos, ArrayList<FixedViewInfo> footViewInfos, ListAdapter adapter) {
              mAdapter = adapter;
              mIsFilterable = adapter instanceof Filterable;
              if (headerViewInfos == null) {
                  mHeaderViewInfos = EMPTY_INFO_LIST;
              } else {
                  mHeaderViewInfos = headerViewInfos;
              }
  
              if (footViewInfos == null) {
                  mFooterViewInfos = EMPTY_INFO_LIST;
              } else {
                  mFooterViewInfos = footViewInfos;
              }
              mAreAllFixedViewsSelectable = areAllListInfosSelectable(mHeaderViewInfos)
                      && areAllListInfosSelectable(mFooterViewInfos);
          }
  
          public void setNumColumns(int numColumns) {
              if (numColumns < 1) {
                  return;
              }
              if (mNumColumns != numColumns) {
                  mNumColumns = numColumns;
                  notifyDataSetChanged();
              }
          }
  
          public void setRowHeight(int height) {
              mRowHeight = height;
          }
  
          public int getHeadersCount() {
              return mHeaderViewInfos.size();
          }
  
          public int getFootersCount() {
              return mFooterViewInfos.size();
          }
  
          @Override
          public boolean isEmpty() {
              return (mAdapter == null || mAdapter.isEmpty()) && getHeadersCount() == 0 && getFootersCount() == 0;
          }
  
          private boolean areAllListInfosSelectable(ArrayList<FixedViewInfo> infos) {
              if (infos != null) {
                  for (FixedViewInfo info : infos) {
                      if (!info.isSelectable) {
                          return false;
                      }
                  }
              }
              return true;
          }
  
          public boolean removeHeader(View v) {
              for (int i = 0; i < mHeaderViewInfos.size(); i++) {
                  FixedViewInfo info = mHeaderViewInfos.get(i);
                  if (info.view == v) {
                      mHeaderViewInfos.remove(i);
                      mAreAllFixedViewsSelectable =
                              areAllListInfosSelectable(mHeaderViewInfos) && areAllListInfosSelectable(mFooterViewInfos);
                      mDataSetObservable.notifyChanged();
                      return true;
                  }
              }
              return false;
          }
  
          public boolean removeFooter(View v) {
              for (int i = 0; i < mFooterViewInfos.size(); i++) {
                  FixedViewInfo info = mFooterViewInfos.get(i);
                  if (info.view == v) {
                      mFooterViewInfos.remove(i);
                      mAreAllFixedViewsSelectable =
                              areAllListInfosSelectable(mHeaderViewInfos) && areAllListInfosSelectable(mFooterViewInfos);
                      mDataSetObservable.notifyChanged();
                      return true;
                  }
              }
              return false;
          }
  
          @Override
          public int getCount() {
              if (mAdapter != null) {
                  return (getFootersCount() + getHeadersCount()) * mNumColumns + getAdapterAndPlaceHolderCount();
              } else {
                  return (getFootersCount() + getHeadersCount()) * mNumColumns;
              }
          }
  
          @Override
          public boolean areAllItemsEnabled() {
              if (mAdapter != null) {
                  return mAreAllFixedViewsSelectable && mAdapter.areAllItemsEnabled();
              } else {
                  return true;
              }
          }
  
          private int getAdapterAndPlaceHolderCount() {
              final int adapterCount = (int) (Math.ceil(1f * mAdapter.getCount() / mNumColumns) * mNumColumns);
              return adapterCount;
          }
  
          @Override
          public boolean isEnabled(int position) {
              // Header (negative positions will throw an IndexOutOfBoundsException)
              int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns;
              if (position < numHeadersAndPlaceholders) {
                  return position % mNumColumns == 0
                          && mHeaderViewInfos.get(position / mNumColumns).isSelectable;
              }
  
              // Adapter
              final int adjPosition = position - numHeadersAndPlaceholders;
              int adapterCount = 0;
              if (mAdapter != null) {
                  adapterCount = getAdapterAndPlaceHolderCount();
                  if (adjPosition < adapterCount) {
                      return adjPosition < mAdapter.getCount() && mAdapter.isEnabled(adjPosition);
                  }
              }
  
              // Footer (off-limits positions will throw an IndexOutOfBoundsException)
              final int footerPosition = adjPosition - adapterCount;
              return footerPosition % mNumColumns == 0
                      && mFooterViewInfos.get(footerPosition / mNumColumns).isSelectable;
          }
  
          @Override
          public Object getItem(int position) {
              // Header (negative positions will throw an ArrayIndexOutOfBoundsException)
              int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns;
              if (position < numHeadersAndPlaceholders) {
                  if (position % mNumColumns == 0) {
                      return mHeaderViewInfos.get(position / mNumColumns).data;
                  }
                  return null;
              }
  
              // Adapter
              final int adjPosition = position - numHeadersAndPlaceholders;
              int adapterCount = 0;
              if (mAdapter != null) {
                  adapterCount = getAdapterAndPlaceHolderCount();
                  if (adjPosition < adapterCount) {
                      if (adjPosition < mAdapter.getCount()) {
                          return mAdapter.getItem(adjPosition);
                      } else {
                          return null;
                      }
                  }
              }
  
              // Footer (off-limits positions will throw an IndexOutOfBoundsException)
              final int footerPosition = adjPosition - adapterCount;
              if (footerPosition % mNumColumns == 0) {
                  return mFooterViewInfos.get(footerPosition).data;
              } else {
                  return null;
              }
          }
  
          @Override
          public long getItemId(int position) {
              int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns;
              if (mAdapter != null && position >= numHeadersAndPlaceholders) {
                  int adjPosition = position - numHeadersAndPlaceholders;
                  int adapterCount = mAdapter.getCount();
                  if (adjPosition < adapterCount) {
                      return mAdapter.getItemId(adjPosition);
                  }
              }
              return -1;
          }
  
          @Override
          public boolean hasStableIds() {
              if (mAdapter != null) {
                  return mAdapter.hasStableIds();
              }
              return false;
          }
  
          @Override
          public View getView(int position, View convertView, ViewGroup parent) {
              if (DEBUG) {
                  Log.d(LOG_TAG, String.format("getView: %s, reused: %s", position, convertView == null));
              }
              // Header (negative positions will throw an ArrayIndexOutOfBoundsException)
              int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns;
              if (position < numHeadersAndPlaceholders) {
                  View headerViewContainer = mHeaderViewInfos
                          .get(position / mNumColumns).viewContainer;
                  if (position % mNumColumns == 0) {
                      return headerViewContainer;
                  } else {
                      if (convertView == null) {
                          convertView = new View(parent.getContext());
                      }
                      // We need to do this because GridView uses the height of the last item
                      // in a row to determine the height for the entire row.
                      convertView.setVisibility(View.INVISIBLE);
                      convertView.setMinimumHeight(headerViewContainer.getHeight());
                      return convertView;
                  }
              }
              // Adapter
              final int adjPosition = position - numHeadersAndPlaceholders;
              int adapterCount = 0;
              if (mAdapter != null) {
                  adapterCount = getAdapterAndPlaceHolderCount();
                  if (adjPosition < adapterCount) {
                      if (adjPosition < mAdapter.getCount()) {
                          View view = mAdapter.getView(adjPosition, convertView, parent);
                          return view;
                      } else {
                          if (convertView == null) {
                              convertView = new View(parent.getContext());
                          }
                          convertView.setVisibility(View.INVISIBLE);
                          convertView.setMinimumHeight(mRowHeight);
                          return convertView;
                      }
                  }
              }
              // Footer
              final int footerPosition = adjPosition - adapterCount;
              if (footerPosition < getCount()) {
                  View footViewContainer = mFooterViewInfos
                          .get(footerPosition / mNumColumns).viewContainer;
                  if (position % mNumColumns == 0) {
                      return footViewContainer;
                  } else {
                      if (convertView == null) {
                          convertView = new View(parent.getContext());
                      }
                      // We need to do this because GridView uses the height of the last item
                      // in a row to determine the height for the entire row.
                      convertView.setVisibility(View.INVISIBLE);
                      convertView.setMinimumHeight(footViewContainer.getHeight());
                      return convertView;
                  }
              }
              throw new ArrayIndexOutOfBoundsException(position);
          }
  
          @Override
          public int getItemViewType(int position) {
  
              final int numHeadersAndPlaceholders = getHeadersCount() * mNumColumns;
              final int adapterViewTypeStart = mAdapter == null ? 0 : mAdapter.getViewTypeCount() - 1;
              int type = AdapterView.ITEM_VIEW_TYPE_HEADER_OR_FOOTER;
              if (mCachePlaceHoldView) {
                  // Header
                  if (position < numHeadersAndPlaceholders) {
                      if (position == 0) {
                          if (mCacheFirstHeaderView) {
                              type = adapterViewTypeStart + mHeaderViewInfos.size() + mFooterViewInfos.size() + 1 + 1;
                          }
                      }
                      if (position % mNumColumns != 0) {
                          type = adapterViewTypeStart + (position / mNumColumns + 1);
                      }
                  }
              }
  
              // Adapter
              final int adjPosition = position - numHeadersAndPlaceholders;
              int adapterCount = 0;
              if (mAdapter != null) {
                  adapterCount = getAdapterAndPlaceHolderCount();
                  if (adjPosition >= 0 && adjPosition < adapterCount) {
                      if (adjPosition < mAdapter.getCount()) {
                          type = mAdapter.getItemViewType(adjPosition);
                      } else {
                          if (mCachePlaceHoldView) {
                              type = adapterViewTypeStart + mHeaderViewInfos.size() + 1;
                          }
                      }
                  }
              }
  
              if (mCachePlaceHoldView) {
                  // Footer
                  final int footerPosition = adjPosition - adapterCount;
                  if (footerPosition >= 0 && footerPosition < getCount() && (footerPosition % mNumColumns) != 0) {
                      type = adapterViewTypeStart + mHeaderViewInfos.size() + 1 + (footerPosition / mNumColumns + 1);
                  }
              }
              if (DEBUG) {
                  Log.d(LOG_TAG, String.format("getItemViewType: pos: %s, result: %s", position, type, mCachePlaceHoldView, mCacheFirstHeaderView));
              }
              return type;
          }
  
          /**
           * content view, content view holder, header[0], header and footer placeholder(s)
           *
           * @return
           */
          @Override
          public int getViewTypeCount() {
              int count = mAdapter == null ? 1 : mAdapter.getViewTypeCount();
              if (mCachePlaceHoldView) {
                  int offset = mHeaderViewInfos.size() + 1 + mFooterViewInfos.size();
                  if (mCacheFirstHeaderView) {
                      offset += 1;
                  }
                  count += offset;
              }
              if (DEBUG) {
                  Log.d(LOG_TAG, String.format("getViewTypeCount: %s", count));
              }
              return count;
          }
  
          @Override
          public void registerDataSetObserver(DataSetObserver observer) {
              mDataSetObservable.registerObserver(observer);
              if (mAdapter != null) {
                  mAdapter.registerDataSetObserver(observer);
              }
          }
  
          @Override
          public void unregisterDataSetObserver(DataSetObserver observer) {
              mDataSetObservable.unregisterObserver(observer);
              if (mAdapter != null) {
                  mAdapter.unregisterDataSetObserver(observer);
              }
          }
  
          @Override
          public Filter getFilter() {
              if (mIsFilterable) {
                  return ((Filterable) mAdapter).getFilter();
              }
              return null;
          }
  
          @Override
          public ListAdapter getWrappedAdapter() {
              return mAdapter;
          }
  
          public void notifyDataSetChanged() {
              mDataSetObservable.notifyChanged();
          }
      }
  }
  