一、概述

本篇博客介绍的是怎样使用SwipeRefreshLayout和RecyclerView实现高仿简书Android端的下拉刷新和上拉载入很多其它的效果。

依据效果图能够发现,本案例实现了例如以下效果:

  • 第一次进入页面显示SwipeRefreshLayout的下拉刷新效果
  • 当内容铺满屏幕时,向下滑动显示“载入中…”效果并载入很多其它数据
  • 当SwipeRefreshLayout正在下拉刷新时,将屏蔽载入很多其它操作
  • 当载入很多其它数据时,屏蔽有可能的反复的上拉操作
  • 当向上滑动RecyclerView时。隐藏Toolbar以获得更好的用户体验

二、代码实现

  • MainActivity
package com.leohan.refresh;

import android.os.Bundle;
import android.os.Handler;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View; import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map; import butterknife.ButterKnife;
import butterknife.InjectView; /**
* @author Leo
*/
public class MainActivity extends AppCompatActivity { @InjectView(R.id.toolbar)
Toolbar toolbar;
@InjectView(R.id.recyclerView)
RecyclerView recyclerView;
@InjectView(R.id.SwipeRefreshLayout)
SwipeRefreshLayout swipeRefreshLayout; boolean isLoading;
private List<Map<String, Object>> data = new ArrayList<>();
private MyAdapter adapter = new MyAdapter(this, data);
private Handler handler = new Handler(); @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_notice);
ButterKnife.inject(this);
initView();
initData();
} public void initView() {
setSupportActionBar(toolbar);
toolbar.setTitle(R.string.notice);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
finish();
}
}); swipeRefreshLayout.setColorSchemeResources(R.color.blueStatus);
swipeRefreshLayout.post(new Runnable() {
@Override
public void run() {
swipeRefreshLayout.setRefreshing(true);
}
}); swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
handler.postDelayed(new Runnable() {
@Override
public void run() {
data.clear();
getData();
}
}, 2000);
}
});
final LinearLayoutManager layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setAdapter(adapter);
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
Log.d("test", "StateChanged = " + newState); } @Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
Log.d("test", "onScrolled"); int lastVisibleItemPosition = layoutManager.findLastVisibleItemPosition();
if (lastVisibleItemPosition + 1 == adapter.getItemCount()) {
Log.d("test", "loading executed"); boolean isRefreshing = swipeRefreshLayout.isRefreshing();
if (isRefreshing) {
adapter.notifyItemRemoved(adapter.getItemCount());
return;
}
if (!isLoading) {
isLoading = true;
handler.postDelayed(new Runnable() {
@Override
public void run() {
getData();
Log.d("test", "load more completed");
isLoading = false;
}
}, 1000);
}
}
}
}); //加入点击事件
adapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() {
@Override
public void onItemClick(View view, int position) {
Log.d("test", "item position = " + position);
} @Override
public void onItemLongClick(View view, int position) { }
});
} public void initData() {
handler.postDelayed(new Runnable() {
@Override
public void run() {
getData();
}
}, 1500); } /**
* 获取測试数据
*/
private void getData() {
for (int i = 0; i < 6; i++) {
Map<String, Object> map = new HashMap<>();
data.add(map);
}
adapter.notifyDataSetChanged();
swipeRefreshLayout.setRefreshing(false);
adapter.notifyItemRemoved(adapter.getItemCount());
} }
  • RecyclerViewAdapter
package com.leohan.refresh;

import android.content.Context;
import android.support.v7.widget.RecyclerView.Adapter;
import android.support.v7.widget.RecyclerView.ViewHolder;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView; import java.util.List; public class RecyclerViewAdapter extends Adapter<ViewHolder> { private static final int TYPE_ITEM = 0;
private static final int TYPE_FOOTER = 1;
private Context context;
private List data; public interface OnItemClickListener {
void onItemClick(View view, int position); void onItemLongClick(View view, int position);
} private OnItemClickListener onItemClickListener; public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
this.onItemClickListener = onItemClickListener;
} @Override
public int getItemCount() {
return data.size() == 0 ? 0 : data.size() + 1;
} @Override
public int getItemViewType(int position) {
if (position + 1 == getItemCount()) {
return TYPE_FOOTER;
} else {
return TYPE_ITEM;
}
} public RecyclerViewAdapter(Context context, List data) {
this.context = context;
this.data = data;
} @Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_ITEM) {
View view = LayoutInflater.from(context).inflate(R.layout.item_notice, parent,
false);
return new ItemViewHolder(view);
} else if (viewType == TYPE_FOOTER) {
View view = LayoutInflater.from(context).inflate(R.layout.item_foot, parent,
false);
return new FootViewHolder(view);
}
return null;
} @Override
public void onBindViewHolder(final ViewHolder holder, int position) {
if (holder instanceof ItemViewHolder) {
//holder.tv.setText(data.get(position));
if (onItemClickListener != null) {
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int position = holder.getLayoutPosition();
onItemClickListener.onItemClick(holder.itemView, position);
}
}); holder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
int position = holder.getLayoutPosition();
onItemClickListener.onItemLongClick(holder.itemView, position);
return false;
}
});
}
}
} static class ItemViewHolder extends ViewHolder { TextView tv; public ItemViewHolder(View view) {
super(view);
tv = (TextView) view.findViewById(R.id.tv_date);
}
} static class FootViewHolder extends ViewHolder { public FootViewHolder(View view) {
super(view);
}
}
}
  • item_base.xml
<?

xml version="1.0" encoding="utf-8"?

>

<android.support.v7.widget.CardView 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="wrap_content"
android:layout_marginLeft="@dimen/margin_10"
android:layout_marginRight="@dimen/margin_10"
android:foreground="?android:attr/selectableItemBackgroundBorderless"
android:layout_marginTop="6dp"
android:orientation="vertical"
app:cardBackgroundColor="@color/line"
app:cardPreventCornerOverlap="true"
app:cardUseCompatPadding="true"
app:contentPadding="6dp"> <LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"> <TextView
android:id="@+id/tv_date"
style="@style/NormalTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="2015-12-11 12:00" /> <android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
app:cardBackgroundColor="@color/white"
app:cardPreventCornerOverlap="true"
app:cardUseCompatPadding="true"
app:contentPadding="10dp"> <TextView
android:id="@+id/tv_title"
style="@style/SmallGreyTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ellipsize="end"
android:maxLines="2"
android:text="视线好转,0729出口开通,0621进口开通。视线好转,0729出口开通,0621进口开通。" /> </android.support.v7.widget.CardView>
</LinearLayout> </android.support.v7.widget.CardView>
  • item_foot.xml
<?

xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="40dp"
android:gravity="center"
android:orientation="horizontal"
> <ProgressBar
android:layout_marginRight="6dp"
android:id="@+id/progressBar"
style="?android:attr/progressBarStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center" /> <TextView
style="@style/SmallGreyTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="@string/loading" /> </LinearLayout>

三、代码分析

  • 上拉载入很多其它数据通过监听RecyclerView的滚动事件RecyclerView.OnScrollListener()实现的。它提供了两个方法:
        /**
* 当RecyclerView的滑动状态改变时触发
*/
public void onScrollStateChanged(RecyclerView recyclerView, int newState){} /**
* 当RecyclerView滑动时触发
* 相似点击事件的MotionEvent.ACTION_MOVE
*/
public void onScrolled(RecyclerView recyclerView, int dx, int dy){}
  • RecyclerView的滑动状态有例如以下三种:
    /**
* The RecyclerView is not currently scrolling.
* 手指离开屏幕
*/
public static final int SCROLL_STATE_IDLE = 0; /**
* The RecyclerView is currently being dragged by outside input such as user touch input.
* 手指触摸屏幕
*/
public static final int SCROLL_STATE_DRAGGING = 1; /**
* The RecyclerView is currently animating to a final position while not under
* outside control.
* 手指加速滑动并放开,此时滑动状态伴随SCROLL_STATE_IDLE
*/
public static final int SCROLL_STATE_SETTLING = 2;
  • 因为简书APP的上拉载入很多其它的是在滑动到最后一个item时自己主动触发的,与手指是否在屏幕上无关。即与滑动状态无关。

    因此,实现这样的效果仅仅须要在public void onScrolled(RecyclerView recyclerView, int dx, int dy) 方法中操作,无需关注当时的滑动状态:

  @Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
Log.d("test", "onScrolled"); int lastVisibleItemPosition = layoutManager.findLastVisibleItemPosition();
if (lastVisibleItemPosition + 1 == adapter.getItemCount()) {
Log.d("test", "loading executed"); boolean isRefreshing = swipeRefreshLayout.isRefreshing();
if (isRefreshing) {
adapter.notifyItemRemoved(adapter.getItemCount());
return;
}
if (!isLoading) {
isLoading = true;
handler.postDelayed(new Runnable() {
@Override
public void run() {
getData();
Log.d("test", "load more completed");
isLoading = false;
}
}, 1000);
}
}
}
  • 假设要实现当且仅当滑动到最后一项而且手指上拉抛出时才运行上拉载入很多其它效果的话。须要配合onScrollStateChanged(RecyclerView recyclerView, int newState的使用,能够将代码改为:
 @Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
Log.d("test", "StateChanged = " + newState);
if (newState == RecyclerView.SCROLL_STATE_IDLE && lastVisibleItemPosition + 1 == adapter.getItemCount()) {
Log.d("test", "loading executed"); boolean isRefreshing = swipeRefreshLayout.isRefreshing();
if (isRefreshing) {
adapter.notifyItemRemoved(adapter.getItemCount());
return;
}
if (!isLoading) {
isLoading = true;
handler.postDelayed(new Runnable() {
@Override
public void run() {
getData();
Log.d("test", "load more completed");
isLoading = false;
}
}, 1000);
}
}
} @Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
Log.d("test", "onScrolled"); lastVisibleItemPosition = layoutManager.findLastVisibleItemPosition(); }
  • 载入很多其它的效果能够通过item_foot.xml自己定义,滑动到最后一项时显示该item并运行载入很多其它。当载入数据完成时须要将该item移除掉
adapter.notifyItemRemoved(adapter.getItemCount());

以下的代码就是RecyclerView的多个item布局的实现方法:

 @Override
public int getItemCount() {
return data.size() == 0 ? 0 : data.size() + 1;
} @Override
public int getItemViewType(int position) {
if (position + 1 == getItemCount()) {
return TYPE_FOOTER;
} else {
return TYPE_ITEM;
}
} @Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == TYPE_ITEM) {
View view = LayoutInflater.from(context).inflate(R.layout.item_base, parent,
false);
return new ItemViewHolder(view);
} else if (viewType == TYPE_FOOTER) {
View view = LayoutInflater.from(context).inflate(R.layout.item_foot, parent,
false);
return new FootViewHolder(view);
}
return null;
}

该案例源代码:https://github.com/leoleohan/RefreshDemo,欢迎Star、Fork。

使用SwipeRefreshLayout和RecyclerView实现仿“简书”下拉刷新和上拉载入很多其它的更多相关文章

  1. Android 5.X新特性之为RecyclerView添加下拉刷新和上拉加载及SwipeRefreshLayout实现原理

    RecyclerView已经写过两篇文章了,分别是Android 5.X新特性之RecyclerView基本解析及无限复用 和 Android 5.X新特性之为RecyclerView添加Header ...

  2. Android实现RecyclerView的下拉刷新和上拉载入很多其它

    需求 先上效果图, Material Design风格的下拉刷新和上拉载入很多其它. 源代码地址(欢迎star) https://github.com/studychen/SeeNewsV2 假设对于 ...

  3. RecyclerView下拉刷新和上拉加载更多实现

    RecyclerView下拉刷新和上拉加载更多实现 转 https://www.jianshu.com/p/4ea7c2d95ecf   在Android开发中,RecyclerView算是使用频率非 ...

  4. 实现RecyclerView下拉刷新和上拉加载更多以及RecyclerView线性、网格、瀑布流效果演示

    实现RecyclerView下拉刷新和上拉加载更多以及RecyclerView线性.网格.瀑布流效果演示 效果预览 实例APP 小米应用商店 使用方法 build.gradle文件 dependenc ...

  5. 手把手教你实现RecyclerView的下拉刷新和上拉加载更多

    手把手教你实现RecyclerView的下拉刷新和上拉加载更多     版权声明:本文为博主原创文章,遵循CC 4.0 by-sa版权协议,转载请附上原文出处链接和本声明. 本文链接:https:// ...

  6. Android 实现下拉刷新和上拉加载更多的RECYCLERVIEW和SCROLLVIEW

    PullRefreshRecyclerView.java /** * 类说明:下拉刷新上拉加载更多的RecyclerView * Author: gaobaiq * Date: 2016/5/9 18 ...

  7. 给RecyclerView最纯粹的下拉刷新和上拉加载更多

    转自 http://blog.csdn.net/jerrywu145/article/details/52225898 http://www.jianshu.com/p/3bf125b4917d

  8. RecyclerView下拉刷新上拉加载(二)

    listview下拉刷新上拉加载扩展(一) http://blog.csdn.net/baiyuliang2013/article/details/50252561 listview下拉刷新上拉加载扩 ...

  9. RecyclerView下拉刷新上拉加载(一)

    listview下拉刷新上拉加载扩展(一) http://blog.csdn.net/baiyuliang2013/article/details/50252561 listview下拉刷新上拉加载扩 ...

随机推荐

  1. MySQL 四种事务隔离级别详解及对比--转

    http://www.jb51.net/article/100183.htm 接的隔离级别.它的语法如下: ? 1 SET [SESSION | GLOBAL] TRANSACTION ISOLATI ...

  2. msxml3.dll 错误 '800c0005' 系统错误: -2146697211。

    asp网站 因为这个问题,困扰自己好多次,还重装过两次服务器系统,非常的麻烦,这次终于找到了问题所在,记录下来,方便以后查看. 服务器症状: 1.服务器上的IE浏览器不能访问外网: 2.set htt ...

  3. (1)HTML声明与基础(已入垃圾筐)

    来自网站http://www.runoob.com/html/html-intro.html <!DOCTYPE/> 声明 Doctype=Document Type=文档类型说明 htt ...

  4. acm练习-day1_1

    “麻雀”lengdan用随机数生成了后台数据,但是笨笨的他被妹纸的问题给难住了... 已知lengdan生成了N(1=<N<=10005)个随机整数,妹子对这些数可能有以下几种操作或询问: ...

  5. C#.NET,技巧篇(DataGridView线程操作)

    这个系列的文章,主要是平时做C#.NET(Framework 3.5)开发的时候,积累的经验和技巧.我们平时总有这样的体会,遇到一个特别难解决的问题,网上寻它千百度也没能搜索到有用的信息.这时你肯定会 ...

  6. Xcode相关概念:Target、Project、Scheme、Workspace

    创建并编译Xcode工程时,有几个常用概念想在这里记一下. Xcode Target: 定义:A target defines a single product; .... 理解:输出文件,等同于VS ...

  7. 安装好Pycharm后如何配置Python解释器简易教程

    呃呃,遇到坑了...... 安装完Python,没有去配置好Python解释器,直接打开Python项目包,去运行程序,程序输出结果只是显示 Process finished with exit co ...

  8. What is JSON

    JSON (JavaScript Object Notation)  是一种轻量级的数据交换格式.它基于ECMAScript的一个子集. JSON具有以下这些形式: 对象是一个无序的“‘名称/值’对” ...

  9. First Project -用函数写的ATM+购物商城程序

    作业需求:模拟实现一个ATM + 购物商城程序 额度15000或自定义 实现购物商城,买东西加入 购物车,调用信用卡接口结账 可以提现,手续费5% 每月22号出账单,每月10号为还款日,过期未还,按欠 ...

  10. sort 及lambda表达式定制排序

    void CDrawCircle::OnBnClickedBtnSelectinfo() { // TODO: 在此添加控件通知处理程序代码 UpdateData(TRUE); BeginEditor ...