MyAdapter 代码实现：
1、 返回Item总数据 header.size+footer.size+datat.size
@Override
public int getItemCount() {
return mFooterViewInfos.size()+mHeaderViewInfos.size() +datas.size();
}
2、 getItemViewType 函数调用
@Override
public int getItemViewType(int position) {
// 如下代码原理：
// 假设getItemCount总数返回有12条 1条头 1条尾
// adjPosition 那么等于 11 0< mHeaderViewInfos.size() 头条
// adjPosition = 1-1 =0 0< 10 条内容 返回ContextView
// adjPosition = 2-1 =1 1< 10
// .......
// adjPosition = 11-1 =10 10< 10 否
// 执行else 那么就 返回footerView
// 12 - 10
final int adjPosition = position - mHeaderViewInfos.size(); // 3 -0
int adapterCount = 0;
adapterCount = datas.size();
if (position < mHeaderViewInfos.size()) {//是头部
return TypeItem.TYPE_HEADER;
// 3 < 10
} else if (adjPosition < adapterCount) { //2 是Center中间部分
Person person = datas.get((position-mHeaderViewInfos.size()));
if (person.getType() == TypeItem.TYPE_A) {
return TypeItem.TYPE_A;
} else if (person.getType() == TypeItem.TYPE_B) {
return TypeItem.TYPE_B;
} else {
return TypeItem.TYPE_CONTEXT;
}
}else{
// 返回footer
return TypeItem.TYPE_FOOTER;
}
}
3、onCreateViewHolder 根据传入的ViewType创建不同类型ViewHolder
4、 onBindViewHolder： 根据不同类型ViewType处理datas数
MyAdapter 核心代码实现：package mk.denganzhi.com.recyclefirstdemo_header;
import android.content.Context;
import android.preference.PreferenceActivity;
import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
/**
* Created by yxm2909 on 2016/7/13.
*/
public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private static final String TAG = "MyAdapter";
private List<Person> datas;
private LayoutInflater inflater;
private OnItemClickListener mOnItemClickListener;
private OnItemLongClickListener mOnItemLongClickListener;
public interface OnItemClickListener {
public void onClick(View parent, int position);
}
public interface OnItemLongClickListener {
public boolean onLongClick(View parent, int position);
}
public void setOnItemClickListener(OnItemClickListener l) {
this.mOnItemClickListener = l;
}
public void setOnItemLongClickListener(OnItemLongClickListener l) {
this.mOnItemLongClickListener = l;
}
private ArrayList<View> mHeaderViewInfos =null;
private ArrayList<View> mFooterViewInfos = null;
public MyAdapter( List<Person> datas) {
this.datas = datas;
}
public MyAdapter(Context context, List<Person> datas,ArrayList<View> headerViewInfos,
ArrayList<View> footerViewInfos) {
if (headerViewInfos == null) {
mHeaderViewInfos = new ArrayList<View>();
} else {
mHeaderViewInfos = headerViewInfos;
}
if (footerViewInfos == null) {
mFooterViewInfos = new ArrayList<View>();
} else {
mFooterViewInfos = footerViewInfos;
}
this.datas = datas;
inflater = LayoutInflater.from(context);
}
// 中间的ViewHolder显示
public class ContextViewHolder extends RecyclerView.ViewHolder {
private View itemView;
private TextView title;
CheckBox checkBox;
public ContextViewHolder(View itemView) {
super(itemView);
this.itemView = itemView;
title = (TextView) itemView.findViewById(R.id.rv_main_item_title);
checkBox= itemView.findViewById(R.id.rv_main_checkbox);
}
}
class AViewHolder extends RecyclerView.ViewHolder{
private TextView textViewA;
public AViewHolder(View itemView) {
super(itemView);
textViewA = (TextView) itemView.findViewById(R.id.item_a);
}
}
class BViewHolder extends RecyclerView.ViewHolder{
private TextView textViewB;
public BViewHolder(View itemView) {
super(itemView);
textViewB = (TextView) itemView.findViewById(R.id.item_b);
}
}
class HeaderViewHolder extends RecyclerView.ViewHolder{
public HeaderViewHolder(View itemView) {
super(itemView);
}
}
class FooterViewHolder extends RecyclerView.ViewHolder{
public FooterViewHolder(View itemView) {
super(itemView);
}
}
ContextViewHolder contextHolder=null;
AViewHolder aViewHolder=null;
BViewHolder bViewHolder=null;
// 头
HeaderViewHolder headerViewHolder;
FooterViewHolder footerViewHolder;
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
Log.e(TAG, "onCreateViewHolder:"+ viewType);
if(TypeItem.TYPE_A == viewType){
aViewHolder=new AViewHolder(inflater.inflate(R.layout.type_a, parent, false));
return aViewHolder;
// B 条目
}else if(TypeItem.TYPE_B == viewType){
bViewHolder=new BViewHolder(inflater.inflate(R.layout.type_b, parent, false));
return bViewHolder;
}else if(TypeItem.TYPE_HEADER == viewType){
headerViewHolder=new HeaderViewHolder(inflater.inflate(R.layout.hader, parent, false));
return headerViewHolder;
}else if(TypeItem.TYPE_FOOTER == viewType){
footerViewHolder=new FooterViewHolder(inflater.inflate(R.layout.footer, parent, false));
return footerViewHolder;
}else {
contextHolder = new ContextViewHolder(inflater.inflate(R.layout.rv_main_item, parent, false));
return contextHolder;
}
}
@Override
public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
Person person=null;
if(holder.getItemViewType() == TypeItem.TYPE_HEADER || holder.getItemViewType() ==TypeItem.TYPE_FOOTER){
}else{
person = datas.get((position-mHeaderViewInfos.size()));
}
// 数据绑定
if(holder.getItemViewType() == TypeItem.TYPE_A){
aViewHolder= (AViewHolder) holder;
aViewHolder.textViewA.setText(person.getName());
}else if(holder.getItemViewType()==TypeItem.TYPE_B){
bViewHolder= (BViewHolder) holder;
bViewHolder.textViewB.setText(person.getName());
}else if(holder.getItemViewType()==TypeItem.TYPE_HEADER){
headerViewHolder= (HeaderViewHolder) holder;
// bViewHolder.textViewB.setText(person.getName());
}
else if(holder.getItemViewType()==TypeItem.TYPE_FOOTER){
footerViewHolder= (FooterViewHolder) holder;
// bViewHolder.textViewB.setText(person.getName());
}else{
contextHolder = (ContextViewHolder)holder;
Log.e(TAG, "set value to item:" + position);
contextHolder.title.setText(person.getName());
if (mOnItemClickListener != null) {
contextHolder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
int pos = contextHolder.getLayoutPosition();
mOnItemClickListener.onClick(contextHolder.itemView, pos);
}
});
}
if (mOnItemLongClickListener != null) {
contextHolder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
int pos = contextHolder.getLayoutPosition();
mOnItemLongClickListener.onLongClick(contextHolder.itemView, pos);
return false;
}
});
}
}
}
// 这里返回的Type传递给创建OnViewHolder的时候
@Override
public int getItemViewType(int position) {
// 假设getItemCount总数返回有12条 1条头 1条尾
// adjPosition 那么等于 11 0< mHeaderViewInfos.size() 头条
// adjPosition = 1-1 =0 0< 10 条内容 返回ContextView
// adjPosition = 2-1 =1 1< 10
// .......
// adjPosition = 11-1 =10 10< 10 否
// 执行else 那么就 返回footerView
// 12 - 10
final int adjPosition = position - mHeaderViewInfos.size(); // 3 -0
int adapterCount = 0;
adapterCount = datas.size();
if (position < mHeaderViewInfos.size()) {//是头部
return TypeItem.TYPE_HEADER;
// 3 < 10
} else if (adjPosition < adapterCount) { //2 是Center中间部分
Person person = datas.get((position-mHeaderViewInfos.size()));
if (person.getType() == TypeItem.TYPE_A) {
return TypeItem.TYPE_A;
} else if (person.getType() == TypeItem.TYPE_B) {
return TypeItem.TYPE_B;
} else {
return TypeItem.TYPE_CONTEXT;
}
}else{
// 返回footer
return TypeItem.TYPE_FOOTER;
}
}
@Override
public int getItemCount() {
return mFooterViewInfos.size()+mHeaderViewInfos.size() +datas.size();
}
}MainActivity 代码实
package mk.denganzhi.com.recyclefirstdemo_header;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private WrapperRecycle wrapperRecycle;
MyAdapter mMyAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView = (RecyclerView) findViewById(R.id.rv_main);
// 默认垂直滚动
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
View headerView1=View.inflate(this,R.layout.hader,null);
ArrayList<View> headerViewInfos=new ArrayList<>();
headerViewInfos.add(headerView1);
ArrayList<View> footerViewInfos=new ArrayList<>();
View footerView1=View.inflate(this,R.layout.footer,null);
footerViewInfos.add(footerView1);
mMyAdapter = new MyAdapter(MainActivity.this, initData(),headerViewInfos,footerViewInfos);
mMyAdapter.setOnItemClickListener(new MyAdapter.OnItemClickListener() {
@Override
public void onClick(View parent, int position) {
}
});
mMyAdapter.setOnItemLongClickListener(new MyAdapter.OnItemLongClickListener() {
@Override
public boolean onLongClick(View parent, int position) {
return false;
}
});
mRecyclerView.setAdapter(mMyAdapter);
}
private List<Person> initData() {
List<Person> datas = new ArrayList<Person>();
for (int i = 0; i <= 100; i++) {
if(i%3==0){
datas.add(new Person(i,"小布什:"+i,TypeItem.TYPE_A));
}else if(i%5==0){
datas.add(new Person(i,"奥巴马:"+i,TypeItem.TYPE_B));
}else{
datas.add(new Person(i,"特兰普:"+i,TypeItem.TYPE_CONTEXT));
}
}
return datas;
}
}
/**/activity_main.xml <?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="mk.denganzhi.com.recyclefirstdemo_header.MainActivity">
<!-- android:background="#000000" -->
<android.support.v7.widget.RecyclerView
android:id="@+id/rv_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
</android.support.v7.widget.RecyclerView>
</LinearLayout>
5. 模仿ListView实现 AddHeader、AddFooter
实现原理：
定义 WrapperRecycle 继承RecyclerView ，定义 addHeaderView 、addFooterView 保存 header、footer
setMyAdapter 的时候刷新新adapdter,
问题？ ： 会调用2次 setAdapter
WrapperRecycle 代码：package mk.denganzhi.com.recyclefirstdemo_header;
import android.app.Activity;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.util.AttributeSet;
import android.view.View;
import java.util.ArrayList;
import java.util.List;
/**
* Created by denganzhi on 2020/3/4.
*/
public class WrapperRecycle extends RecyclerView {
private ArrayList<View> mHeaderViewInfos = new ArrayList<View>();
private ArrayList<View> mFooterViewInfos = new ArrayList<View>();
private Adapter mAdapter;
public WrapperRecycle(Context context, AttributeSet attrs) {
super(context, attrs);
}
public void addHeaderView(View v) {
mHeaderViewInfos.add(v);
}
public void addFooterView(View v) {
mFooterViewInfos.add(v);
}
public void setMyAdapter(Activity activity, List<Person> datass,Adapter adapter) {
if (mHeaderViewInfos.size() > 0|| mFooterViewInfos.size() > 0) {
mAdapter = new MyAdapter( activity, datass,mHeaderViewInfos,mFooterViewInfos);
} else {
mAdapter = adapter;
}
setAdapter(mAdapter);
}
}
MainActivity 实现代码：package mk.denganzhi.com.recyclefirstdemo_header;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private WrapperRecycle wrapperRecycle;
MyAdapter mMyAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
wrapperRecycle = (WrapperRecycle) findViewById(R.id.rv_main1);
wrapperRecycle.setLayoutManager(new LinearLayoutManager(this));
View headerView1=View.inflate(this,R.layout.hader,null);
View footerView1=View.inflate(this,R.layout.footer,null);
// 添加headerView
wrapperRecycle.addHeaderView(headerView1);
// 添加footerView
wrapperRecycle.addFooterView(footerView1);
// 第一个newAdapter
MyAdapter adapter = new MyAdapter(initData());
// setAdapter内部还会调用内部带有header、footerview的adapter
// new Adapter以后Adapter内部会回调
// getItemCount 、onCreateViewHolder、onBindViewHolder 对应方法
wrapperRecycle.setMyAdapter(MainActivity.this, initData(),adapter);
}
private List<Person> initData() {
List<Person> datas = new ArrayList<Person>();
for (int i = 0; i <= 100; i++) {
if(i%3==0){
datas.add(new Person(i,"小布什:"+i,TypeItem.TYPE_A));
}else if(i%5==0){
datas.add(new Person(i,"奥巴马:"+i,TypeItem.TYPE_B));
}else{
datas.add(new Person(i,"特兰普:"+i,TypeItem.TYPE_CONTEXT));
}
}
return datas;
}
}
/**/上图看效果：
