android中RecyclerView的简单使用（四）——上下拉刷新的实现

上一篇讲述了recyclerview实现瀑布流，而在本篇中将讲述recycler view实现上下拉刷新。（附加嵌套checkbox错乱问题的解决）

代码中添加了较为详细的注释，就不多说了，直接贴代码。

代码如下：

首先，先贴出Adapter中的代码。

package com.example.cn.bgs.swiprecycleviewdemo;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.RecyclerView.ViewHolder;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.ProgressBar;
import android.widget.TextView;

public class MyAdapter extends RecyclerView.Adapter<ViewHolder> {
	private Context context;
	private List<String> list;
	// 加载的状态
	private int loadState = LOADING;
	// 两种view的类型
	private static final int ITEM_VIEW = 1;
	private static final int FOOTER_VIEW = 2;
	// 底部视图的两种方式-加载更多 和 没有更多数据了
	private static final int LOADING = 3;
	private static final int NO_MORE = 4;
	private boolean isChecked;
	
	private Map<Integer,Boolean> map=new HashMap<Integer,Boolean>();

	public MyAdapter(Context context, List<String> list) {
		this.context = context;
		this.list = list;
	}
	/*
	 * 获得相应位置视图的类型
	 */

	@Override
	public int getItemViewType(int position) {
		// TODO Auto-generated method stub
		if (position + 1 == getItemCount()) {
			//底部视图
			return FOOTER_VIEW;
		} else {
			//条目试图
			return ITEM_VIEW;
		}

	}
	/*
	 * 设置适配器加载的状态（加载更多和没有更多）
	 */

	public void setloadState(int state) {
		this.loadState = state;
		notifyDataSetChanged();
	}

	@Override
	public int getItemCount() {
		// TODO Auto-generated method stub
		return list.size() + 1;
	}

	@Override
	public void onBindViewHolder(ViewHolder holder, final int pos) {
		// TODO Auto-generated method stub
		if (holder instanceof ItemHolder) {
			((ItemHolder) holder).mtv.setText(list.get(pos));
			 final Integer tag=new Integer(pos);
			 ((ItemHolder) holder).mcb.setTag(tag);
			  if(map.containsKey(tag)){
				  ((ItemHolder) holder).mcb.setChecked(map.get(tag)); 
			  }else{
				  ((ItemHolder) holder).mcb.setChecked(false);
			  }
			  ((ItemHolder) holder).mcb.setOnCheckedChangeListener(new OnCheckedChangeListener() {
				
				@Override
				public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
					// TODO Auto-generated method stub
					if(!isChecked){
						map.put(tag, true);
					}else{
						map.put(tag, false);
					}
				}
			});
			  
			
		}
		if (holder instanceof FooterHolder) {
			//判断底部视图加载状态
			switch (loadState) {
			case LOADING:
				((FooterHolder) holder).mpb.setVisibility(View.VISIBLE);
				((FooterHolder) holder).mtv.setText("正在加载更多数据...");
				break;
			case NO_MORE:
				((FooterHolder) holder).mpb.setVisibility(View.GONE);
				((FooterHolder) holder).mtv.setText("没有更多数据了...");
				break;
			}
		}
	}

	@Override
	public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
		// TODO Auto-generated method stub
		//根据viewHolder判断布局的加载
		switch (viewType) {
		case ITEM_VIEW:
			View v = LayoutInflater.from(context).inflate(R.layout.item,
					parent, false);
			ItemHolder holder = new ItemHolder(v);
			return holder;

		case FOOTER_VIEW:
			View fv = LayoutInflater.from(context).inflate(R.layout.footer,
					parent, false);
			FooterHolder fholder = new FooterHolder(fv);
			return fholder;
		}
		return null;

	}

}

class ItemHolder extends ViewHolder {
	public TextView mtv;
	public CheckBox mcb;

	public ItemHolder(View v) {
		super(v);
		// TODO Auto-generated constructor stub
		mtv = (TextView) v.findViewById(R.id.mtv);
		mcb=(CheckBox) v.findViewById(R.id.mcb);
	}

}

class FooterHolder extends ViewHolder {
	public ProgressBar mpb;
	public TextView mtv;

	public FooterHolder(View v) {
		super(v);
		// TODO Auto-generated constructor stub
		mpb = (ProgressBar) v.findViewById(R.id.mpb);
		mtv = (TextView) v.findViewById(R.id.mtv);
	}

}

然后就是MainActivity中的代码：

package com.example.cn.bgs.swiprecycleviewdemo;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.os.Handler;
import android.app.Activity;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v4.widget.SwipeRefreshLayout.OnRefreshListener;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.RecyclerView.OnScrollListener;
import android.view.Menu;

public class MainActivity extends Activity {
	private RecyclerView mrv;
	private SwipeRefreshLayout mswip;
	private MyAdapter adapter;
	//判断是否加载数据
	private boolean isLoading;
	//当前页面能见的最后一个item的id
	private int lastId;
	private int state;
	private LinearLayoutManager linearManager;
	//能显示的数据最大值
	private int maxSize = 48;
	//底部视图的两种状态
	private static final int LOADING = 3;
	private static final int NO_MORE = 4;
	private List<String> list = new ArrayList<String>();
	

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		mrv = (RecyclerView) findViewById(R.id.mrv);
		linearManager = new LinearLayoutManager(this);
		mswip = (SwipeRefreshLayout) findViewById(R.id.mswip);
		list = new ArrayList<String>();
	
		for (int i = 0; i < 20; i++) {
			list.add("item" + i);
		}
		adapter = new MyAdapter(this, list);
		mrv.setAdapter(adapter);
		mrv.setLayoutManager(linearManager);
		mswip.setColorSchemeResources(R.color.color1, R.color.color2,
				R.color.color3, R.color.color4);
		//下拉刷新的监听
		mswip.setOnRefreshListener(new OnRefreshListener() {

			@Override
			public void onRefresh() {
				// TODO Auto-generated method stub
				new Handler().postDelayed(new Runnable() {

					@Override
					public void run() {
						// TODO Auto-generated method stub
						for (int i = 5; i > 0; i--) {
							list.add(0, "new item" + i);

						}
						adapter.notifyDataSetChanged();
						mswip.setRefreshing(false);
					}
				}, 3000);
			}
		});
        //上拉加载的监听
		mrv.setOnScrollListener(new OnScrollListener() {

			@Override
			public void onScrolled(int arg0, int arg1) {
				// TODO Auto-generated method stub
				//mrv滑动的时候会回调这个方法
				lastId = linearManager.findLastVisibleItemPosition();
			}

			@Override
			public void onScrollStateChanged(int arg0) {
				// TODO Auto-generated method stub
				//判断是否是最后一条
				if (lastId + 1 == adapter.getItemCount()
						&& state == RecyclerView.SCROLL_STATE_IDLE
						&& !isLoading) {
					isLoading = true;
					final int count = adapter.getItemCount();
					new Handler().postDelayed(new Runnable() {

						@Override
						public void run() {
							// TODO Auto-generated method stub
							//判断是否加载到最大值了
							if (count + 10 < maxSize) {
								for (int i = count; i < count + 10; i++) {
									list.add("load more" + i);
								}
								adapter.notifyDataSetChanged();
							} else {
								for (int i = count; i < maxSize; i++) {
									list.add("load more" + i);
								}
								adapter.setloadState(NO_MORE);
							}
							isLoading = false;
						}
					}, 3000);
				}
			}
		});
	}

}

以上四篇文章就是我对recycler v iew的了解，如有不足或者欠缺的地方，还望多多指教。