带标题的RecyclerViewAdapter

public class SectionedGridRecyclerViewAdapter extends RecyclerView.Adapter {    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 mSections = new SparseArray();    private RecyclerView mRecyclerView;    public SectionedGridRecyclerViewAdapter(Context context, int sectionResourceId, int textResourceId,RecyclerView recyclerView,                                            RecyclerView.Adapter baseAdapter) {        mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);        mSectionResourceId = sectionResourceId;        mTextResourceId = textResourceId;        mBaseAdapter = baseAdapter;        mContext = context;        mRecyclerView = recyclerView;        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);            }        });        final GridLayoutManager layoutManager = (GridLayoutManager)(mRecyclerView.getLayoutManager());        layoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {            @Override            public int getSpanSize(int position) {                return (isSectionHeaderPosition(position))? layoutManager.getSpanCount() : 1 ;            }        });    }    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() {            @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);    }}

绑定适配器
在RecyclerView执行完setLayoutManager（）方法后

      List.Section> sections = new ArrayList.Section>();        sections.add(new SectionedGridRecyclerViewAdapter.Section(**X**, "**标题**"));        sections.add(new SectionedGridRecyclerViewAdapter.Section(**Y**, "**标题**"));        SectionedGridRecyclerViewAdapter.Section[] dummy = new SectionedGridRecyclerViewAdapter.Section[sections.size()];        SectionedGridRecyclerViewAdapter mSectionedAdapter = new                SectionedGridRecyclerViewAdapter(getActivity(), **标题的布局**, **标题的Id**, **RecyclerView对象**, **RecyclerView的适配器**);        mSectionedAdapter.setSections(sections.toArray(dummy));

X：第一个标题出现在第几个Item的位置
Y：第二个标题出现在第几个Item的位置
当然RecyclerView的Item足够多的时候，标题也可以继续添加

更多相关文章

随机推荐