Android RecyclerView上拉加载和下拉刷新（基础版）

这里讲述的是用谷歌原生的SwipeRefreshLayout，进行刷新，以及利用RecycleView的滚动事件，判断是否到最后一个item，进行加载更多，这里加载更多是在RecycleView的适配器中使用不同item进行完成的。

这是activity的xml布局：

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <android.support.v4.widget.SwipeRefreshLayout  android:id="@+id/swipe_refresh_layout"  android:layout_width="match_parent"  android:layout_height="match_parent"  >  <android.support.v7.widget.RecyclerView   android:id="@+id/recyclerview"   android:layout_width="match_parent"   android:layout_height="match_parent"   android:background="#F0F0F0"   android:clipToPadding="false"   android:paddingBottom="16dp"   android:paddingTop="16dp"/> </android.support.v4.widget.SwipeRefreshLayout> <com.rey.material.widget.ProgressView  android:id="@+id/progress_loading_main"  app:pv_autostart="true"  app:pv_circular="true"   app:pv_progressStyle="@style/Material.Drawable.CircularProgress"  app:pv_progressMode="indeterminate"  android:layout_width="50dp"  android:layout_height="50dp"  android:visibility="gone"  android:layout_centerInParent="true"/></RelativeLayout>

接下来是对应activity中的代码：

import android.os.Bundle;import android.os.Handler;import android.support.annotation.Nullable;import android.support.design.widget.Snackbar;import android.support.v4.app.Fragment;import android.support.v4.widget.SwipeRefreshLayout;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import com.retrofit.wangfei.viewpagertablayout.util.Constance;import com.retrofit.wangfei.viewpagertablayout.R;import com.retrofit.wangfei.viewpagertablayout.adapter.MyRecycleViewAdapter;import com.rey.material.widget.ProgressView;import java.util.ArrayList;import java.util.List;import butterknife.Bind;import butterknife.ButterKnife;public class HomeFragment extends Fragment { @Bind(R.id.recyclerview) RecyclerView recyclerview; @Bind(R.id.swipe_refresh_layout) SwipeRefreshLayout swipeRefreshLayout; @Bind(R.id.progress_loading_main) ProgressView progress_loading_main; // 加载数据时显示的进度圆圈 private LinearLayoutManager mRecycleViewLayoutManager; private int mPageNum = 1; private List<String> lists = new ArrayList<>(); private MyRecycleViewAdapter mAdapter; public static HomeFragment newInstance() {  HomeFragment fragment = new HomeFragment();  return fragment; } @Override public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container,        Bundle savedInstanceState) {  View view = inflater.inflate(R.layout.fragment_home, container, false);  ButterKnife.bind(this, view);  return view; } /**在onCreateView方法后执行*/ @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {  super.onViewCreated(view, savedInstanceState);  mAdapter = new MyRecycleViewAdapter(lists,getActivity());  initRecyclerView();  swipeRefreshLayout.setColorSchemeResources(Constance.colors);//设置下拉刷新控件变换的四个颜色  recyclerview.setAdapter(mAdapter);  recyclerViewOnItemClickListener();  refresh();  loadMore(mAdapter);  progress_loading_main.setVisibility(View.VISIBLE);  initData(); } @Override public void onDestroyView() {  super.onDestroyView();  ButterKnife.unbind(this); } /**进入页面的初始化数据*/ private void initData(){  new Handler().postDelayed(new Runnable() {   @Override   public void run() {    netNewsList(true);    progress_loading_main.setVisibility(View.GONE);   }  }, 2000); } /**RecyclerView每个item的点击事件*/ private void recyclerViewOnItemClickListener() {  mAdapter.setOnItemClickListener(new MyRecycleViewAdapter.OnItemClickListener() {   @Override   public void onItemClick(View view, int position) {    Snackbar.make(view, "fly", Snackbar.LENGTH_SHORT).show();   }  }); } /**  * 初始化RecyclerView  */ private void initRecyclerView() {//  recyclerview.setItemAnimator(new DefaultItemAnimator());//  recyclerview.setHasFixedSize(true);  mRecycleViewLayoutManager = new LinearLayoutManager(getActivity());  recyclerview.setLayoutManager(mRecycleViewLayoutManager); // 设置RecycleView，显示是ListView还是gridView还是瀑布流 } /**下拉刷新*/ private void refresh() {  swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {   @Override   public void onRefresh() {    new Handler().postDelayed(new Runnable() {     @Override     public void run() {      netNewsList(true);      swipeRefreshLayout.setRefreshing(false); // 停止刷新     }    }, 2000);   }  }); } /**  * 设置上拉加载更多  *  * @param adapter RecyclerView适配器  */ public void loadMore(final MyRecycleViewAdapter adapter) {  recyclerview.addOnScrollListener(new RecyclerView.OnScrollListener() {   private int lastVisibleItem;   @Override   public void onScrolled(RecyclerView recyclerView, int dx, int dy) {    super.onScrolled(recyclerView, dx, dy);    lastVisibleItem = mRecycleViewLayoutManager.findLastVisibleItemPosition(); // 滑动到最后一个   }   @Override   public void onScrollStateChanged(RecyclerView recyclerView, int newState) {    super.onScrollStateChanged(recyclerView, newState);    // 效果在暂停时显示, 否则会导致重绘异常    if (newState == RecyclerView.SCROLL_STATE_IDLE      && lastVisibleItem + 1 == adapter.getItemCount()) {     if (lists != null && lists.size() >= 10) { // 真实开发中要设置mNews.size()大于加载分页显示的个数      adapter.loadLayout.setVisibility(View.VISIBLE);      //加载更多      new Handler().postDelayed(new Runnable() {       @Override       public void run() {        netNewsList(false);       }      }, 2000);     }    }   }  }); } /**  * 从网络加载数据列表  *  * @param isRefresh 是否刷新 true 为刷新，false为不刷新  */ private void netNewsList(boolean isRefresh) {//  viewDelegate.showLoading();  if (isRefresh) {   mPageNum = 1;  } else {   mPageNum++;  }  if (isRefresh) {   if (!lists.isEmpty()) {    lists.clear();   }  }  // TODO 这里把页数mPageNum上传到服务端  lists.clear();  lists.addAll(getData());  mAdapter.notifyDataSetChanged(); } private List<String> list = new ArrayList<>(); private List<String> getData() {  for (int i = 0; i < 10; i++) {   list.add(i + "");  }  return list; }}

接下来是RecycleView适配器中的xml文件：

这是正常item的布局，至于用CardView是为了让item展示出来的效果更好看

<?xml version="1.0" encoding="utf-8"?><android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="wrap_content"> <TextView  android:id="@+id/text"  android:layout_width="match_parent"  android:layout_height="50dp"  android:text=""  android:gravity="center"/></android.support.v7.widget.CardView>

这是现实上拉加载的布局文件，作为不同item共同展示在RecycleView上面：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/load_layout" android:visibility="gone" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:orientation="horizontal" android:paddingBottom="12dip" android:paddingTop="12dip"> <com.rey.material.widget.ProgressView  app:pv_autostart="true"  app:pv_circular="true"  app:pv_progressStyle="@style/Material.Drawable.CircularProgress"  app:pv_progressMode="indeterminate"  android:layout_width="24dp"  android:layout_height="24dp" /> <TextView  android:id="@+id/more_data_msg"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:textSize="16sp"  android:layout_marginLeft="10dp"  android:text="正在加载..." /></LinearLayout>

下面我们看看RecycleView适配器的写法：

import android.app.Activity;import android.support.v7.widget.RecyclerView;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.LinearLayout;import android.widget.TextView;import com.retrofit.wangfei.viewpagertablayout.R;import java.util.List;import butterknife.Bind;import butterknife.ButterKnife;/** * Created by Android Studio * Description: RecycleView的适配器 */public class MyRecycleViewAdapter extends RecyclerView.Adapter { private final static int TYPE_ITEM = 0X01; private final static int TYPE_FOOTER = 0x02; private List<String> lists; private Activity context; public LinearLayout loadLayout; private OnItemClickListener mOnItemClickListener; // 声明接口 public MyRecycleViewAdapter(List<String> lists, Activity context) {  this.lists = lists;  this.context = context; } @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {  if (TYPE_ITEM == viewType) {   View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycle_view_item, parent,false);   ItemViewHolder itemViewHolder = new ItemViewHolder(view);   return itemViewHolder;  } else {   View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_footer, parent,false);   loadLayout = (LinearLayout) view.findViewById(R.id.load_layout);   return new FootViewHolder(view);  } } @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {  if (holder instanceof ItemViewHolder) {   String text = lists.get(position);   ItemViewHolder itemHolder = (ItemViewHolder) holder;   itemHolder.text.setText(text);  } } @Override public int getItemCount() {  return lists.size() + 1; } @Override public int getItemViewType(int position) {  if (position + 1 == getItemCount()) {   return TYPE_FOOTER;  } else {   return TYPE_ITEM;  } } public class ItemViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {  @Bind(R.id.text)  TextView text;  public ItemViewHolder(View itemView) {   super(itemView);   ButterKnife.bind(this,itemView);   itemView.setOnClickListener(this);  }  @Override  public void onClick(View v) {   mOnItemClickListener.onItemClick(v,getPosition());  } } public class FootViewHolder extends RecyclerView.ViewHolder {  public FootViewHolder(View itemView) {   super(itemView);  } } /**调到外部使用*/ public void setOnItemClickListener(OnItemClickListener onItemClickListener){  this.mOnItemClickListener = onItemClickListener; } /**定义接口*/ public interface OnItemClickListener{  void onItemClick(View v,int position); }}

最后是刷新控件的4个不同颜色：

public interface Constance { /**  * 下拉刷新控件变化的四个颜色  */ int[] colors = new int[] {   android.R.color.holo_green_light, android.R.color.holo_blue_light,   android.R.color.holo_green_light, android.R.color.holo_blue_light };}

所需要的依赖库：

compile 'com.android.support:appcompat-v7:23.3.0' compile 'com.android.support:design:23.3.0' compile 'com.jakewharton:butterknife:7.0.1' compile 'com.android.support:support-v4:23.3.0' /**谷歌服务*/ compile 'com.google.android.gms:play-services:8.4.0' compile 'com.github.rey5137:material:1.2.2'

到这里就结束了，完成了下拉刷新和上拉加载更多的实现。

下面说说RecyclerView的使用最基础的三点：

一：

recyclerview.setHasFixedSize(true); //方法用来使RecyclerView保持固定的大小，该信息被用于自身的优化。

二：

recyclerview.setItemAnimator(new DefaultItemAnimator()); ItemAnimator会根据适配器上收到的通知动画显示视图组的修改。基本上，它会自动显示添加和移除条目动画。这也不是一个简单的类，但我们发现DefaultItemAnimator已经可以运行得很好了。

三：

recyclerview.setLayoutManager(mRecycleViewLayoutManager); // 设置RecycleView，显示是ListView还是gridView还是瀑布流。// 显示是ListView LinearLayoutManager mRecycleViewLayoutManager = new LinearLayoutManager(context);// 显示是gridView,参数一：上下文，参数二：列数 GridLayoutManager mGridLayoutManager=new GridLayoutManager(context, 4);// 显示是瀑布流，参数一：显示几列，参数二：现实的方向，垂直或水平 StaggeredGridLayoutManager mStaggeredGridLayoutManager=new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);

更多详细请参考：Android RecyclerView艺术般的控件使用完全解析

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。

每一幢房子都有一种不同的颜色，