讓RecyclerView上拉刷新下拉加載更多更簡便易用

效果圖

dd.gif

說明

1.本demo使用的數據,均由gank.io提供

2.下拉刷新使用的是SwipeRefreshLayout

3.上拉加載更多使用的是BRVAH提供的BaseRecyclerViewAdapterHelper:2.1.3

抽取接口

public interface IPagingService<T extends List> {
    /**


 * 加載分頁數據
 * @param page 加載第幾頁
 * @param limit 1頁加載多少條
 */
void getData(int page,int limit, Observer<T> observer);

}</code></pre> 
  
編寫基類(實現分頁邏輯)
 
  
public class BasePagingActivity<T> extends AppCompatActivity implements SwipeRefreshLayout.OnRefreshListener, BaseQuickAdapter.RequestLoadMoreListener {
    private static final int PAGE_SIZE = 20;
    private RecyclerView mRecyclerView;
    private BaseQuickAdapter mQuickAdapter;
    private IPagingService<List<T>> mPagingService;
    private SwipeRefreshLayout mSwipeRefreshLayout;
    private int currentPage;
    private int lastPage;


private void setSwipeRefreshLayout(SwipeRefreshLayout swipeRefreshLayout) {
    if (swipeRefreshLayout != null) {
        mSwipeRefreshLayout = swipeRefreshLayout;
        mSwipeRefreshLayout.setProgressBackgroundColorSchemeResource(android.R.color.white);
        mSwipeRefreshLayout.setProgressViewOffset(false, 0, (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 24, getResources().getDisplayMetrics()));
        mSwipeRefreshLayout.setColorSchemeResources(android.R.color.holo_blue_light, android.R.color.holo_red_light, android.R.color.holo_orange_light, android.R.color.holo_green_light);
        swipeRefreshLayout.setOnRefreshListener(this);
    } else {
        throw new NullPointerException("swipeRefreshLayout not null");
    }
}

private void setRecyclerView(RecyclerView recyclerView) {
    mRecyclerView = recyclerView;
    if (mRecyclerView.getLayoutManager() == null) {
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
    }
}

private void setQuickAdapter(BaseQuickAdapter quickAdapter) {
    if (quickAdapter != null) {
        mQuickAdapter = quickAdapter;
        mQuickAdapter.openLoadAnimation();
        mQuickAdapter.openLoadMore(PAGE_SIZE);
        mQuickAdapter.setOnLoadMoreListener(this);
        mRecyclerView.setAdapter(quickAdapter);
    } else {
        throw new NullPointerException("swipeRefreshLayout not null");
    }
}

/**
* 開始獲取數據,提供給子類調用
*/
protected void startGetData(RecyclerView recyclerView,SwipeRefreshLayout swipeRefreshLayout,BaseQuickAdapter quickAdapter, IPagingService<List<T>> pagingService){
    mPagingService = pagingService;
    setRecyclerView(recyclerView);
    setSwipeRefreshLayout(swipeRefreshLayout);
    setQuickAdapter(quickAdapter);
    onLoadFirstData();
}

@Override
public void onRefresh() {
    currentPage = 1;
    mPagingService.getData(currentPage, PAGE_SIZE, new Observer<List<T>>() {
        @Override
        public void onCompleted() {

        }

        @Override
        public void onError(Throwable e) {
            Toast.makeText(BasePagingActivity.this,e.getMessage(),Toast.LENGTH_SHORT).show();
            mSwipeRefreshLayout.setRefreshing(false);
            currentPage = lastPage;
        }

        @Override
        public void onNext(List<T> list) {
            if (list == null) return;
            mQuickAdapter.getData().clear();
            mQuickAdapter.addData(list);
            mQuickAdapter.notifyDataSetChanged();
            mSwipeRefreshLayout.setRefreshing(false);
        }
    });
}

@Override
public void onLoadMoreRequested() {
    lastPage = currentPage;
    currentPage++;
    mPagingService.getData(currentPage, PAGE_SIZE, new Observer<List<T>>() {
        @Override
        public void onCompleted() {

        }

        @Override
        public void onError(Throwable e) {
            Toast.makeText(BasePagingActivity.this,e.getMessage(),Toast.LENGTH_SHORT).show();
            currentPage = lastPage;
        }

        @Override
        public void onNext(List<T> list) {
            if ((list != null && list.isEmpty())) {
                Toast.makeText(BasePagingActivity.this,"沒有更多數據了",Toast.LENGTH_SHORT).show();
                mQuickAdapter.addData(list);
                mQuickAdapter.loadComplete();
            } else {
                mQuickAdapter.addData(list);
            }
            lastPage = currentPage;
        }
    });
}

public void onLoadFirstData(){
    lastPage = currentPage = 1;
    mSwipeRefreshLayout.setRefreshing(true);
    mPagingService.getData(currentPage, PAGE_SIZE, new Observer<List<T>>() {
        @Override
        public void onCompleted() {

        }

        @Override
        public void onError(Throwable e) {
            Toast.makeText(BasePagingActivity.this,e.getMessage(),Toast.LENGTH_SHORT).show();
            mSwipeRefreshLayout.setRefreshing(false);
        }

        @Override
        public void onNext(List<T> list) {
            if (list == null) return;
            mQuickAdapter.addData(list);
            mQuickAdapter.notifyDataSetChanged();
            mSwipeRefreshLayout.setRefreshing(false);
        }
    });
}

}</code></pre> 
  
fragment同樣可以這樣做
 
  
使用
 
  
1.實現IPagingService
 
  
public class WelfareServer implements IPagingService<List<WelfareEntity>>{
        @Override
        public void getData(int page, int limit, Observer<List<WelfareEntity>> observer) {
            RetrofitManager.getInstance().createReq(GankIo.class)
                    .getWelfareImg(limit, page)
                    .subscribeOn(Schedulers.io())
                    .observeOn(AndroidSchedulers.mainThread())
                    .subscribe(observer);
        }
    }
 
  
2.繼承BasePagingActivity并調用startGetData方法
 
  
public class MainActivity extends BasePagingActivity<WelfareEntity> {


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    SwipeRefreshLayout mSwipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.refresh_layout);
    RecyclerView mRecyclerView = (RecyclerView) findViewById(R.id.list);
    startGetData(mRecyclerView, mSwipeRefreshLayout, new BaseQuickAdapter<WelfareEntity>(R.layout.item_welfare,new ArrayList()){
        @Override
        protected void convert(BaseViewHolder baseViewHolder, WelfareEntity welfareEntity) {
            Glide.with(MainActivity.this)
                    .load(welfareEntity.getUrl())
                    .placeholder(R.mipmap.load_image_bg)
                    .into((ImageView) baseViewHolder.getView(R.id.iv));
        }
    },new WelfareServer());

}

}</code></pre> 
  
 
 
  
 
 
  
來自：http://www.jianshu.com/p/f3c3a84c2e99