Android为TV端助力 转载:RecyclerView分页加载

package com.android.ryane.pulltoloaddata_recyclerview;

import android.os.Handler;
import android.os.Looper;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity implements SwipeRefreshLayout.OnRefreshListener {
private SwipeRefreshLayout refreshLayout;
private RecyclerView recyclerView;
private List<String> list;

private int lastVisibleItem = 0;
private final int PAGE_COUNT = 10;
private GridLayoutManager mLayoutManager;
private MyAdapter adapter;
private Handler mHandler = new Handler(Looper.getMainLooper());

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

initData();
findView();
initRefreshLayout();
initRecyclerView();
}

private void initData() {
list = new ArrayList<>();
for (int i = 1; i <= 40; i++) {
list.add("条目" + i);
}
}

private void findView() {
refreshLayout = (SwipeRefreshLayout) findViewById(R.id.refreshLayout);
recyclerView = (RecyclerView) findViewById(R.id.recyclerView);

}

private void initRefreshLayout() {
refreshLayout.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);
refreshLayout.setOnRefreshListener(this);
}

private void initRecyclerView() {
adapter = new MyAdapter(getDatas(0, PAGE_COUNT), this, getDatas(0, PAGE_COUNT).size() > 0 ? true : false);
mLayoutManager = new GridLayoutManager(this, 1);
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setAdapter(adapter);
recyclerView.setItemAnimator(new DefaultItemAnimator());

recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (newState == RecyclerView.SCROLL_STATE_IDLE) {
if (adapter.isFadeTips() == false && lastVisibleItem + 1 == adapter.getItemCount()) {
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
updateRecyclerView(adapter.getRealLastPosition(), adapter.getRealLastPosition() + PAGE_COUNT);
}
}, 500);
}

if (adapter.isFadeTips() == true && lastVisibleItem + 2 == adapter.getItemCount()) {
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
updateRecyclerView(adapter.getRealLastPosition(), adapter.getRealLastPosition() + PAGE_COUNT);
}
}, 500);
}
}
}

@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
lastVisibleItem = mLayoutManager.findLastVisibleItemPosition();
}
});
}

private List<String> getDatas(final int firstIndex, final int lastIndex) {
List<String> resList = new ArrayList<>();
for (int i = firstIndex; i < lastIndex; i++) {
if (i < list.size()) {
resList.add(list.get(i));
}
}
return resList;
}

private void updateRecyclerView(int fromIndex, int toIndex) {
List<String> newDatas = getDatas(fromIndex, toIndex);
if (newDatas.size() > 0) {
adapter.updateList(newDatas, true);
} else {
adapter.updateList(null, false);
}
}

@Override
public void onRefresh() {
refreshLayout.setRefreshing(true);
adapter.resetDatas();
updateRecyclerView(0, PAGE_COUNT);
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
refreshLayout.setRefreshing(false);
}
}, 1000);
}
}

package com.android.ryane.pulltoloaddata_recyclerview;

import android.content.Context;
import android.os.Handler;
import android.os.Looper;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

/**
* Created by lijianchang@yy.com on 2017/4/12.
*/

public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private List<String> datas;
private Context context;
private int normalType = 0;
private int footType = 1;
private boolean hasMore = true;
private boolean fadeTips = false;
private Handler mHandler = new Handler(Looper.getMainLooper());

public MyAdapter(List<String> datas, Context context, boolean hasMore) {
this.datas = datas;
this.context = context;
this.hasMore = hasMore;
}

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == normalType) {
return new NormalHolder(LayoutInflater.from(context).inflate(R.layout.item, null));
} else {
return new FootHolder(LayoutInflater.from(context).inflate(R.layout.footview, null));
}
}

@Override
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
if (holder instanceof NormalHolder) {
((NormalHolder) holder).textView.setText(datas.get(position));
} else {
((FootHolder) holder).tips.setVisibility(View.VISIBLE);
if (hasMore == true) {
fadeTips = false;
if (datas.size() > 0) {
((FootHolder) holder).tips.setText("正在加载更多...");
}
} else {
if (datas.size() > 0) {
((FootHolder) holder).tips.setText("没有更多数据了");
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
((FootHolder) holder).tips.setVisibility(View.GONE);
fadeTips = true;
hasMore = true;
}
}, 500);
}
}
}
}

@Override
public int getItemCount() {
return datas.size() + 1;
}

public int getRealLastPosition() {
return datas.size();
}

public void updateList(List<String> newDatas, boolean hasMore) {
if (newDatas != null) {
datas.addAll(newDatas);
}
this.hasMore = hasMore;
notifyDataSetChanged();
}

class NormalHolder extends RecyclerView.ViewHolder {
private TextView textView;

public NormalHolder(View itemView) {
super(itemView);
textView = (TextView) itemView.findViewById(R.id.tv);
}
}

class FootHolder extends RecyclerView.ViewHolder {
private TextView tips;

public FootHolder(View itemView) {
super(itemView);
tips = (TextView) itemView.findViewById(R.id.tips);
}
}

public boolean isFadeTips() {
return fadeTips;
}

public void resetDatas() {
datas = new ArrayList<>();
}

@Override
public int getItemViewType(int position) {
if (position == getItemCount() - 1) {
return footType;
} else {
return normalType;
}
}
}

尊重原著，原文地址：https://github.com/OnlyYouMyLove/PullToLoadData-RecyclerView