gordonpassy · November 12, 2015 20:36 · Jan 15, 2015 · Jan 15, 2015 · Aug 16, 2014 · Aug 16, 2014
diff --git a/SimpleAdapter.java b/SimpleAdapter.java
@@ -0,0 +1,55 @@
+public class SimpleAdapter extends RecyclerView.Adapter<SimpleAdapter.SimpleViewHolder> {
+
+    private final Context mContext;
+    private List<String> mData;
+
+    public void add(String s,int position) {
+        position = position == -1 ? getItemCount()  : position;
+        mData.add(position,s);
+        notifyItemInserted(position);
+    }
+
+    public void remove(int position){
+        if (position < getItemCount()  ) {
+            mData.remove(position);
+            notifyItemRemoved(position);
+        }
+    }
+
+    public static class SimpleViewHolder extends RecyclerView.ViewHolder {
+        public final TextView title;
+
+        public SimpleViewHolder(View view) {
+            super(view);
+            title = (TextView) view.findViewById(R.id.simple_text);
+        }
+    }
+
+    public SimpleAdapter(Context context, String[] data) {
+        mContext = context;
+        if (data != null)
+            mData = new ArrayList<String>(Arrays.asList(data));
+        else mData = new ArrayList<String>();
+    }
+
+    public SimpleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+        final View view = LayoutInflater.from(mContext).inflate(R.layout.simple_item, parent, false);
+        return new SimpleViewHolder(view);
+    }
+
+    @Override
+    public void onBindViewHolder(SimpleViewHolder holder, final int position) {
+        holder.title.setText(mData.get(position));
+        holder.title.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                Toast.makeText(mContext,"Position ="+position,Toast.LENGTH_SHORT).show();
+            }
+        });
+    }
+
+    @Override
+    public int getItemCount() {
+        return mData.size();
+    }
+}
diff --git a/Readme.md b/Readme.md
@@ -5,6 +5,8 @@ You can use this code also with the `TwoWayView` with the `ListLayoutManager` (h
 
 This is a porting of the class `SimpleSectionedListAdapter` provided by [Google](https://github.com/google/iosched/blob/master/android/src/main/java/com/google/samples/apps/iosched/ui/SimpleSectionedListAdapter.java)
 
+![Screen](http://3.bp.blogspot.com/-7UducuzfXm0/VLhP1c6lypI/AAAAAAAAkNA/NbJm_Bj142E/s400/Screenshot_2014-08-16-20-55-02.png)
+
 Example:
 ```java
         //Your RecyclerView

diff --git a/Readme.md b/Readme.md
@@ -1,6 +1,9 @@
 You can use this class to realize a simple sectioned `RecyclerView.Adapter` without changing your code.
 
 The `RecyclerView` should use a `LinearLayoutManager`.
+You can use this code also with the `TwoWayView` with the `ListLayoutManager` (https://github.com/lucasr/twoway-view)
+
+This is a porting of the class `SimpleSectionedListAdapter` provided by [Google](https://github.com/google/iosched/blob/master/android/src/main/java/com/google/samples/apps/iosched/ui/SimpleSectionedListAdapter.java)
 
 Example:
 ```java

diff --git a/Readme.md b/Readme.md
@@ -0,0 +1,39 @@
+You can use this class to realize a simple sectioned `RecyclerView.Adapter` without changing your code.
+
+The `RecyclerView` should use a `LinearLayoutManager`.
+
+Example:
+```java
+        //Your RecyclerView
+        mRecyclerView = (RecyclerView) findViewById(R.id.list);
+        mRecyclerView.setHasFixedSize(true);
+        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
+        mRecyclerView.addItemDecoration(new DividerItemDecoration(this,LinearLayoutManager.VERTICAL));
+
+        //Your RecyclerView.Adapter
+        mAdapter = new SimpleAdapter(this,sCheeseStrings);
+
+
+        //This is the code to provide a sectioned list
+        List<SimpleSectionedRecyclerViewAdapter.Section> sections =
+                new ArrayList<SimpleSectionedRecyclerViewAdapter.Section>();
+
+        //Sections
+        sections.add(new SimpleSectionedRecyclerViewAdapter.Section(0,"Section 1"));
+        sections.add(new SimpleSectionedRecyclerViewAdapter.Section(5,"Section 2"));
+        sections.add(new SimpleSectionedRecyclerViewAdapter.Section(12,"Section 3"));
+        sections.add(new SimpleSectionedRecyclerViewAdapter.Section(14,"Section 4"));
+        sections.add(new SimpleSectionedRecyclerViewAdapter.Section(20,"Section 5"));
+
+        //Add your adapter to the sectionAdapter
+        SimpleSectionedRecyclerViewAdapter.Section[] dummy = new SimpleSectionedRecyclerViewAdapter.Section[sections.size()];
+        SimpleSectionedRecyclerViewAdapter mSectionedAdapter = new
+                  SimpleSectionedRecyclerViewAdapter(this,R.layout.section,R.id.section_text,mAdapter);
+        mSectionedAdapter.setSections(sections.toArray(dummy));
+
+        //Apply this adapter to the RecyclerView
+        mRecyclerView.setAdapter(mSectionedAdapter);
+```
+
+You can customize the section layout, changing the layout section.xml and changing the code in the `SimpleSectionedRecyclerViewAdapter.SectionViewHolder` class and `SimpleSectionedRecyclerViewAdapter#onBindViewHolder` method.
+
diff --git a/SimpleSectionedRecyclerViewAdapter.java b/SimpleSectionedRecyclerViewAdapter.java
@@ -0,0 +1,170 @@
+public class SimpleSectionedRecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
+
+    private final Context mContext;
+    private static final int SECTION_TYPE = 0;
+
+    private boolean mValid = true;
+    private int mSectionResourceId;
+    private int mTextResourceId;
+    private LayoutInflater mLayoutInflater;
+    private RecyclerView.Adapter mBaseAdapter;
+    private SparseArray<Section> mSections = new SparseArray<Section>();
+
+
+    public SimpleSectionedRecyclerViewAdapter(Context context, int sectionResourceId, int textResourceId,
+                                              RecyclerView.Adapter baseAdapter) {
+
+        mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
+        mSectionResourceId = sectionResourceId;
+        mTextResourceId = textResourceId;
+        mBaseAdapter = baseAdapter;
+        mContext = context;
+
+        mBaseAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
+            @Override
+            public void onChanged() {
+                mValid = mBaseAdapter.getItemCount()>0;
+                notifyDataSetChanged();
+            }
+
+            @Override
+            public void onItemRangeChanged(int positionStart, int itemCount) {
+                mValid = mBaseAdapter.getItemCount()>0;
+                notifyItemRangeChanged(positionStart, itemCount);
+            }
+
+            @Override
+            public void onItemRangeInserted(int positionStart, int itemCount) {
+                mValid = mBaseAdapter.getItemCount()>0;
+                notifyItemRangeInserted(positionStart, itemCount);
+            }
+
+            @Override
+            public void onItemRangeRemoved(int positionStart, int itemCount) {
+                mValid = mBaseAdapter.getItemCount()>0;
+                notifyItemRangeRemoved(positionStart, itemCount);
+            }
+        });
+    }
+
+
+    public static class SectionViewHolder extends RecyclerView.ViewHolder {
+
+        public TextView title;
+
+        public SectionViewHolder(View view,int mTextResourceid) {
+            super(view);
+            title = (TextView) view.findViewById(mTextResourceid);
+        }
+    }
+
+    @Override
+    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int typeView) {
+        if (typeView == SECTION_TYPE) {
+            final View view = LayoutInflater.from(mContext).inflate(mSectionResourceId, parent, false);
+            return new SectionViewHolder(view,mTextResourceId);
+        }else{
+            return mBaseAdapter.onCreateViewHolder(parent, typeView -1);
+        }
+    }
+
+    @Override
+    public void onBindViewHolder(RecyclerView.ViewHolder sectionViewHolder, int position) {
+        if (isSectionHeaderPosition(position)) {
+            ((SectionViewHolder)sectionViewHolder).title.setText(mSections.get(position).title);
+        }else{
+            mBaseAdapter.onBindViewHolder(sectionViewHolder,sectionedPositionToPosition(position));
+        }
+
+    }
+
+    @Override
+    public int getItemViewType(int position) {
+        return isSectionHeaderPosition(position)
+                ? SECTION_TYPE
+                : mBaseAdapter.getItemViewType(sectionedPositionToPosition(position)) +1 ;
+    }
+
+
+    public static class Section {
+        int firstPosition;
+        int sectionedPosition;
+        CharSequence title;
+
+        public Section(int firstPosition, CharSequence title) {
+            this.firstPosition = firstPosition;
+            this.title = title;
+        }
+
+        public CharSequence getTitle() {
+            return title;
+        }
+    }
+
+
+    public void setSections(Section[] sections) {
+        mSections.clear();
+
+        Arrays.sort(sections, new Comparator<Section>() {
+            @Override
+            public int compare(Section o, Section o1) {
+                return (o.firstPosition == o1.firstPosition)
+                        ? 0
+                        : ((o.firstPosition < o1.firstPosition) ? -1 : 1);
+            }
+        });
+
+        int offset = 0; // offset positions for the headers we're adding
+        for (Section section : sections) {
+            section.sectionedPosition = section.firstPosition + offset;
+            mSections.append(section.sectionedPosition, section);
+            ++offset;
+        }
+
+        notifyDataSetChanged();
+    }
+
+    public int positionToSectionedPosition(int position) {
+        int offset = 0;
+        for (int i = 0; i < mSections.size(); i++) {
+            if (mSections.valueAt(i).firstPosition > position) {
+                break;
+            }
+            ++offset;
+        }
+        return position + offset;
+    }
+
+    public int sectionedPositionToPosition(int sectionedPosition) {
+        if (isSectionHeaderPosition(sectionedPosition)) {
+            return RecyclerView.NO_POSITION;
+        }
+
+        int offset = 0;
+        for (int i = 0; i < mSections.size(); i++) {
+            if (mSections.valueAt(i).sectionedPosition > sectionedPosition) {
+                break;
+            }
+            --offset;
+        }
+        return sectionedPosition + offset;
+    }
+
+    public boolean isSectionHeaderPosition(int position) {
+        return mSections.get(position) != null;
+    }
+
+
+    @Override
+    public long getItemId(int position) {
+        return isSectionHeaderPosition(position)
+                ? Integer.MAX_VALUE - mSections.indexOfKey(position)
+                : mBaseAdapter.getItemId(sectionedPositionToPosition(position));
+    }
+
+    @Override
+    public int getItemCount() {
+        return (mValid ? mBaseAdapter.getItemCount() + mSections.size() : 0);
+    }
+
+}
diff --git a/section.xml b/section.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<TextView xmlns:android="http://schemas.android.com/apk/res/android"
+          android:layout_width="match_parent"
+          android:layout_height="48dp"
+          android:gravity="center_vertical"
+          android:paddingLeft="16dp"
+          android:singleLine="true"
+          android:textAllCaps="true"
+          android:textColor="@color/demo_theme_status_bar_color"
+          android:background="@android:color/transparent"
+          android:textSize="16sp"
+          android:id="@+id/section_text"
+          android:textStyle="bold" />