- 不关心Item是否显示在正确的位置，如何显示。（LayoutManager）
- 不关心Item间如何分隔。（ItemDecoration）
- 不关心Item增加与删除的动画效果。（ItemAnimator）
- 仅仅关注如何回收与复用View。
RecylerView相关的重要类
- Adapter
- ViewHolder
- LayoutManager
- ItemDecoration
- ItemAnimator
RecylerView能干什么？
- Just like ListView
- Just like GridView
- 横向 ListView
- 横向 GridView
- 瀑布流
- 定制Item增加与删除动画（ItemAnimator）
- 需要手动为Adapter提供Item Click/longClick的回调
RecyclerView关于ListView的实现代码：
package cn.jiarong.myrecyclerview;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends ActionBarActivity {
private RecyclerView mRecyclerView;
private List<String> mDatas;
private MyAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initDatas();
initViews();
adapter = new MyAdapter(this, mDatas);
mRecyclerView.setAdapter(adapter);
//设置RecyclerView的布局管理
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this,
LinearLayoutManager.VERTICAL, false);
mRecyclerView.setLayoutManager(linearLayoutManager);
mRecyclerView.setItemAnimator(new DefaultItemAnimator());
//设置RecyclerView的item的分割线
//mRecyclerView.addItemDecoration(new DividerItemDecoration(this,
//DividerItemDecoration.VERTICAL_LIST));
adapter.setmOnItemClickListner(new MyAdapter.OnItemClickListener() {
@Override
public void onItemClick(View v, int pos) {
Toast.makeText(MainActivity.this, pos +" click:",Toast.LENGTH_SHORT).show();
}
@Override
public void onItemLongClick(View v, int pos) {
Toast.makeText(MainActivity.this, pos +" long click:",Toast.LENGTH_SHORT).show();
}
});
}
//加载视图
private void initViews(){
mRecyclerView = (RecyclerView)findViewById(R.id.mRecyclerView);
}
//初始化数据
private void initDatas(){
mDatas = new ArrayList<String>();
for(int i='A';i<='z';i++){
mDatas.add(""+(char)i);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
switch (id){
case R.id.action_add:
adapter.addData(1, "insert a");
break;
case R.id.action_delete:
adapter.deleteData(1);
break;
case R.id.action_listview:
mRecyclerView.setLayoutManager(new LinearLayoutManager(this,
LinearLayoutManager.VERTICAL, false));
break;
case R.id.action_gridview:
mRecyclerView.setLayoutManager(new GridLayoutManager(this, 3));
break;
case R.id.action_hor_gridview:
mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(5,
StaggeredGridLayoutManager.HORIZONTAL));
break;
case R.id.action_staggered:
Intent intent = new Intent(this, StaggedActivity.class);
startActivity(intent);
break;
}
return super.onOptionsItemSelected(item);
}
}
package cn.jiarong.myrecyclerview;
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.ViewGroup;
import android.widget.TextView;
import java.util.List;
/**
* Created by jiaronggeng on 15/6/25.
*/
public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
private LayoutInflater mInflater;
private Context mContext;
protected List<String> mDatas;
public interface OnItemClickListener{
public void onItemClick(View v, int pos);
public void onItemLongClick(View v, int pos);
}
private OnItemClickListener mOnItemClickListner;
public void setmOnItemClickListner(OnItemClickListener mOnItemClickListner) {
this.mOnItemClickListner = mOnItemClickListner;
}
public void addData(int pos, String str){
this.mDatas.add(pos, str);
this.notifyItemInserted(1);
}
public void deleteData(int pos){
this.mDatas.remove(pos);
this.notifyItemRemoved(1);
}
public MyAdapter(Context context, List<String> datas){
this.mContext = context;
this.mDatas = datas;
mInflater = LayoutInflater.from(context);
}
@Override
public void onBindViewHolder(final MyViewHolder myViewHolder, final int i) {
myViewHolder.m_tv.setText(mDatas.get(i));
setUpEvent(myViewHolder);
}
protected void setUpEvent(final MyViewHolder myViewHolder){
if (mOnItemClickListner != null) {
myViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int pos = myViewHolder.getLayoutPosition();
mOnItemClickListner.onItemClick(myViewHolder.itemView, pos);
}
});
myViewHolder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
int pos = myViewHolder.getLayoutPosition();
mOnItemClickListner.onItemLongClick(myViewHolder.itemView, pos);
return false;
}
});
}
}
@Override
public int getItemCount() {
return mDatas.size();
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = mInflater.inflate(R.layout.item, viewGroup, false);
MyViewHolder viewHolder = new MyViewHolder(view);
return viewHolder;
}
}
class MyViewHolder extends ViewHolder{
TextView m_tv;
public MyViewHolder(View itemView) {
super(itemView);
m_tv = (TextView)itemView.findViewById(R.id.m_tv);
}
}
瀑布流
package cn.jiarong.myrecyclerview;
import android.app.Activity;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import java.util.ArrayList;
import java.util.List;
public class StaggedActivity extends Activity {
private RecyclerView mRecyclerView;
private List<String> mDatas;
private StaggedAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initDatas();
initViews();
adapter = new StaggedAdapter(this, mDatas);
mRecyclerView.setAdapter(adapter);
//设置RecyclerView的布局管理
mRecyclerView.setLayoutManager(new StaggeredGridLayoutManager(3,
StaggeredGridLayoutManager.VERTICAL));
adapter.setmOnItemClickListner(new MyAdapter.OnItemClickListener() {
@Override
public void onItemClick(View v, int pos) {
}
@Override
public void onItemLongClick(View v, int pos) {
//长按删除
adapter.deleteData(pos);
}
});
}
//加载视图
private void initViews(){
mRecyclerView = (RecyclerView)findViewById(R.id.mRecyclerView);
}
//初始化数据
private void initDatas(){
mDatas = new ArrayList<String>();
for(int i='A';i<='z';i++){
mDatas.add(""+(char)i);
}
}
}
package cn.jiarong.myrecyclerview;
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.ViewGroup;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
/**
* Created by jiaronggeng on 15/6/25.
*/
public class StaggedAdapter extends MyAdapter {
private List<Integer> listHeight;
public StaggedAdapter(Context context, List<String> datas){
super(context, datas);
listHeight = new ArrayList<Integer>();
for(int i=0;i<mDatas.size();i++){
listHeight.add((int)(100+Math.random()*300));
}
}
@Override
public void onBindViewHolder(MyViewHolder myViewHolder, int position) {
ViewGroup.LayoutParams lp = myViewHolder.itemView.getLayoutParams();
lp.height = listHeight.get(position);
myViewHolder.itemView.setLayoutParams(lp);
myViewHolder.m_tv.setText(mDatas.get(position));
setUpEvent(myViewHolder);
}
}
