[Android-Util]#Android

BasePaginationAdapter.java

/**
 * Created by Tendoasan on 2017/8/15.
 * 基础分页适配器
 */
@SuppressWarnings("unused")
public abstract class BasePaginationAdapter<T> extends Adapter {

    public interface PaginationListener {
        void onLoadMoreItems();
    }

    protected List<T> mItems;

    private boolean mIsLoading;
    private boolean mHasMoreItems;
    private PaginationListener mPaginationListener;
    private boolean mIsPaging;

    private LinearLayoutManager mLayoutManger;

    // 初始化
    public void init(RecyclerView rv, boolean isPaging) {

        mIsPaging = isPaging;
        mIsLoading = false;

        if (rv.getLayoutManager() != null && rv.getLayoutManager() instanceof LinearLayoutManager){
            mLayoutManger = (LinearLayoutManager)rv.getLayoutManager();
        }

        if(mIsPaging){
            // 底部加载更多
            rv.addOnScrollListener(new RecyclerView.OnScrollListener() {
                @Override
                public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                    super.onScrolled(recyclerView, dx, dy);

                    if(mLayoutManger == null){
                        return;
                    }

                    int visibleItemCount = mLayoutManger.getChildCount();
                    int totalItemCount = mLayoutManger.getItemCount();
                    int firstVisibleItemPosition = mLayoutManger.findFirstVisibleItemPosition();

                    // 不在加载+还有更多选项+底部
                    if (!mIsLoading && mHasMoreItems
                            && ((visibleItemCount + firstVisibleItemPosition) >= totalItemCount)) {
                        if (mPaginationListener != null) {
                            setLoading(true);
                            mPaginationListener.onLoadMoreItems();
                        }
                    }
                }
            });
        }
    }

    public void onFinishLoading(boolean hasMoreItems) {
        setLoading(false);
        setHasMoreItems(hasMoreItems);
    }

    @Override
    public int getItemViewType(int position) {
        if(mItems != null && position == mItems.size()){
            return RecyclerView.INVALID_TYPE;
        }
        return super.getItemViewType(position);
    }

    public void clearData() {
        if(mItems != null){
            mItems.clear();
            this.notifyDataSetChanged();
        }
    }

    @Override
    public int getItemCount() {
        return mItems == null ? 0  : mItems.size();
        //ic_dial_new is for loadingView
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
        return initViewHolder(viewGroup,viewType);
    }

    @Override
    public void onBindViewHolder(ViewHolder viewHolder, int position) {
        doBindViewHolder(viewHolder, position);
    }

    protected abstract ViewHolder initViewHolder(ViewGroup viewGroup, int viewType);
    protected abstract void doBindViewHolder(ViewHolder viewHolder, int position);

    public void setItems(List<T> items){
        mItems = items;
    }

    public List<T> getItems(){
        return mItems;
    }

    public boolean isLoading() {
        return mIsLoading;
    }

    public void setLoading(boolean isLoading) {
        mIsLoading = isLoading;
    }

    public void setHasMoreItems(boolean hasMoreItems) {
        this.mHasMoreItems = hasMoreItems;

    }

    public boolean isHasMoreItems() {
        return mHasMoreItems;
    }

    public void setPaginationListener(PaginationListener paginationListener) {
        this.mPaginationListener = paginationListener;
    }

}