前言：我們在使用RecyclerView的過程中其實還是有很多問題的，前面提到的沒有預設的分割線，很是讓人蛋疼啊，但現在有出了個問題，不能新增頭部和底部，這一度讓我認為這貨還是沒有最愛的ListView好用啊，哈哈，既然谷歌出來了，我們就要使用，沒有頭和腳那我們就給他造出頭和腳，可以仿照ListView那樣優雅的實現。

翔神封裝的過於強大，對於我這樣的小白來說只能是以後學習的物件，大家不妨看一下我的

分析：如果想自己動手也封裝一個頭部和尾部，那只有參考ListView是如何封裝的，大家看一下ListView的關鍵程式碼，是不是就明白了很多

ListView.addHeaderView(){
	 if (mAdapter != null) {
            if (!(mAdapter instanceof HeaderViewListAdapter)) {
                mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, mAdapter);
            }
};
ListView.setAdapter(){
	if (mHeaderViewInfos.size() > 0|| mFooterViewInfos.size() > 0) {
            mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, adapter);
        } else {
            mAdapter = adapter;
        }
}
 

import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.RecyclerView.Adapter;
import android.view.View;
import android.view.ViewGroup;

import java.util.ArrayList;

/**
 * Created by Fly on 2017/5/15.
 */

public class WrapRecyclerViewAdapter extends RecyclerView.Adapter {
    private Adapter mAdapter;
    private ArrayList<View> mHeaderViewInfos;
    private ArrayList<View> mFooterViewInfos;

    public WrapRecyclerViewAdapter(ArrayList<View> headerViewInfos, ArrayList<View> footerViewInfos, Adapter adapter) {
        mAdapter = adapter;

        if (headerViewInfos == null) {
            mHeaderViewInfos = new ArrayList<View>();
        } else {
            mHeaderViewInfos = headerViewInfos;
        }

        if (footerViewInfos == null) {
            mFooterViewInfos = new ArrayList<View>();
        } else {
            mFooterViewInfos = footerViewInfos;
        }
    }

    @Override
    public int getItemCount() {
        if (mAdapter != null) {
            return getFootersCount() + getHeadersCount() + mAdapter.getItemCount();
        } else {
            return getFootersCount() + getHeadersCount();
        }
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        //也要劃分三個區域
        int numHeaders = getHeadersCount();
        if (position < numHeaders) {//是頭部
            return;
        }
        //adapter body
        final int adjPosition = position - numHeaders;
        int adapterCount = 0;
        if (mAdapter != null) {
            adapterCount = mAdapter.getItemCount();
            if (adjPosition < adapterCount) {
                mAdapter.onBindViewHolder(holder, adjPosition);
                return;
            }
        }
    }

    @Override
    public int getItemViewType(int position) {
        //判斷當前條目是什麼型別的---決定渲染什麼檢視給什麼資料
        int numHeaders = getHeadersCount();
        if (position < numHeaders) {//是頭部
            return RecyclerView.INVALID_TYPE;
        }
        //正常條目部分
        // Adapter
        final int adjPosition = position - numHeaders;
        int adapterCount = 0;
        if (mAdapter != null) {
            adapterCount = mAdapter.getItemCount();
            if (adjPosition < adapterCount) {
                return mAdapter.getItemViewType(adjPosition);
            }
        }
        //footer部分
        return RecyclerView.INVALID_TYPE - 1;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        //header
        if (viewType == RecyclerView.INVALID_TYPE) {
            return new HeaderViewHolder(mHeaderViewInfos.get(0));
        } else if (viewType == RecyclerView.INVALID_TYPE - 1) {//footer
            return new HeaderViewHolder(mFooterViewInfos.get(0));
        }
        return mAdapter.onCreateViewHolder(parent, viewType);
    }

    public int getHeadersCount() {
        return mHeaderViewInfos.size();
    }

    public int getFootersCount() {
        return mFooterViewInfos.size();
    }

    private static class HeaderViewHolder extends RecyclerView.ViewHolder {

        public HeaderViewHolder(View view) {
            super(view);
        }
    }
}
 

我們footerView和headerView的Adapter封裝好了，接下來肯定也要重新改造下RecyclerView這個類，打造能接收HeaderView和FooterView的RecyclerView：

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.view.View;

import java.util.ArrayList;

public class WrapRecyclerView extends RecyclerView {
    private ArrayList<View> mHeaderViewInfos = new ArrayList<View>();
    private ArrayList<View> mFooterViewInfos = new ArrayList<View>();
    private Adapter mAdapter;

    public WrapRecyclerView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public void addHeaderView(View v) {
        mHeaderViewInfos.add(v);

        // Wrap the adapter if it wasn't already wrapped.
        if (mAdapter != null) {
            if (!(mAdapter instanceof WrapRecyclerViewAdapter)) {
                mAdapter = new WrapRecyclerViewAdapter(mHeaderViewInfos, mFooterViewInfos, mAdapter);
            }
        }
    }

    public void addFooterView(View v) {
        mFooterViewInfos.add(v);
        // Wrap the adapter if it wasn't already wrapped.
        if (mAdapter != null) {
            if (!(mAdapter instanceof WrapRecyclerViewAdapter)) {
                mAdapter = new WrapRecyclerViewAdapter(mHeaderViewInfos, mFooterViewInfos, mAdapter);
            }
        }
    }

    @Override
    public void setAdapter(Adapter adapter) {
        if (mHeaderViewInfos.size() > 0 || mFooterViewInfos.size() > 0) {
            mAdapter = new WrapRecyclerViewAdapter(mHeaderViewInfos, mFooterViewInfos, adapter);
        } else {
            mAdapter = adapter;
        }
        super.setAdapter(mAdapter);
    }
}
 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.fly.rv02.MainActivity">

    <com.fly.rv02.WrapRecyclerView
        android:id="@+id/rv"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</RelativeLayout>

在程式碼中新增頭部和尾部：

View headerView = View.inflate(this, R.layout.header, null);
mRecyclerView.addHeaderView(headerView);

View footerView = View.inflate(this, R.layout.footer, null);
mRecyclerView.addFooterView(footerView);

大功告成，大家趕緊去嘗試一下吧！！！