android 控件 swipe+recycler 分页基类

1抽取接口

public interface IPagingService<T extends List> {
    /**
     * 加载分页数据
     * @param page 加载第几页
     * @param limit 1页加载多少条
     */
    void getData(int page,int limit, Observer<T> observer);

}

编写基类(实现分页逻辑)

//上拉加载更多，下拉刷新基类，并时间接口
public class BasePagingActivity<T> extends AppCompatActivity implements SwipeRefreshLayout.OnRefreshListener, BaseQuickAdapter.RequestLoadMoreListener {
    private static final int PAGE_SIZE = 20;//显示数量
    private RecyclerView mRecyclerView; //recyclerview
    private BaseQuickAdapter mQuickAdapter; //adapter
    private IPagingService<List<T>> mPagingService;
    private SwipeRefreshLayout mSwipeRefreshLayout;
    private int currentPage;
    private int lastPage;


//初始化Swipe
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");
        }
    }


//初始化recyclerview
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");
        }
    }


    /**
    * 开始获取数据,提供给子类调用
    */
protected void startGetData(RecyclerView recyclerView,SwipeRefreshLayout swipeRefreshLayout,BaseQuickAdapter quickAdapter, IPagingService<List<T>> pagingService){
        mPagingService = pagingService;
        setRecyclerView(recyclerView);
        setSwipeRefreshLayout(swipeRefreshLayout);
        setQuickAdapter(quickAdapter);
        onLoadFirstData();
    }


//下拉刷新接口实现,page=1,失败:mSwipeRefreshLayout隐藏,成功:list数据为空停止.有数据则,adapter数据清空,再添加数据.notify.mSwipeRefreshLayout隐藏
 @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);
            }
        });
    }


//上拉加载更多,lastPage有数据的page值,currentpage为交互page.失败的话把currentpage置回lastpage.
//成功:数据为空和失败处理的方式一样.有数据:lastPage设置为currentpage,adapter添加数据.
@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,"没有更多数据了",Toast.LENGTH_SHORT).show();
                    mQuickAdapter.addData(list);
                    mQuickAdapter.loadComplete();
                } else {
                    mQuickAdapter.addData(list);
                }
                lastPage = currentPage;
            }
        });
    }


//初始化最开始的数据
    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);
            }
        });
    }
}

使用
1.实现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.继承BasePagingActivity并调用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 WelfareServer());


    }
}