Android RecyclerView之ListView显示(二)
效果图
垂直显示(标准显示) 垂直反向显示 水平显示 水平反向显示
Android RecyclerView之ListView显示
本博文讲述了运用RecyclerView替代ListView
在Android RecyclerView详解(一)中已经介绍过了RecyclerView的基本运用接下来我要使用强大RecyclerView来显示ListView的效果。
1.将RecyclerView添加到布局文件并关联兼容包(注意:低版本的安卓系统,要进行兼容包的关联)
步骤:按住control+alt+shift+s出现Project Structure按下图所示关联
关联成功后在主布局文件activity_main中添加RecyclerView
2.在与主类MainActivity同级下新建一个包名为menu在包中新建一个类为DateBean用于归纳信息
3.新建一个行布局名为list_item,并添加一个ImageView和TextView
<? xml version= "1.0" encoding= "utf-8" ?>< RelativeLayout xmlns: android = "http://schemas.android.com/apk/res/android"android :layout_width= "match_parent"android :layout_height= "wrap_content" >< ImageViewandroid :id= "@+id/item_list_icon"android :layout_width= "100dp"android :layout_height= "100dp"android :src= "@mipmap/ic_launcher" />< TextViewandroid :id= "@+id/item_list_name"android :layout_width= "match_parent"android :layout_height= "wrap_content"android :layout_centerVertical= "true"android :layout_toRightOf= "@+id/item_list_icon"android :text= "图片描述"android :textSize= "28sp"android :textStyle= "bold" /></ RelativeLayout >
4.在res文件下新建一个包为menu在包中建一个menu布局文件用于显示下拉菜单
如果想了解详细的Menu菜单栏详细使用可以点击:Android Menu菜单栏
<? xml version= "1.0" encoding= "utf-8" ?>< menu xmlns: android = "http://schemas.android.com/apk/res/android"xmlns: app = "http://schemas.android.com/apk/res-auto" >< itemandroid :id= "@+id/action_ListView"android :orderInCategory= "100"android :title= "ListView显示"app :showAsAction= "never" >< menu >< itemandroid :id= "@+id/action_ListView_noraml"android :orderInCategory= "100"android :title= "标准"app :showAsAction= "never" />< itemandroid :id= "@+id/action_ListView_vertical_reverse"android :orderInCategory= "100"android :title= "垂直反向"app :showAsAction= "never" />< itemandroid :id= "@+id/action_ListView_horizontal"android :orderInCategory= "100"android :title= "水平"app :showAsAction= "never" />< itemandroid :id= "@+id/action_ListView_horizontal_reverse"android :orderInCategory= "100"android :title= "水平反向"app :showAsAction= "never" /></ menu ></ item ></ menu >
5.RecyclerView适配器,
RecyclerView适配器的详细介绍可以点击:Android RecyclerView详解(一)
package com.example.recyclerview_activity.adapter;import android.content.Context;import android.support.v7.widget.RecyclerView;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;import android.widget.TextView;import com.example.recyclerview_activity.R;import com.example.recyclerview_activity.menu.DateBean;import java.util.List;/*** Date:2017/3/14* author:陈箫阳ChenXiaoYang* furction:RecycleView的适配器注意要指定泛型,一般我们就是类名的ViewHodler继承ViewHodler(内部已经实现了复用优化机制)*/public class RecyclerViewListAdapter extends RecyclerView.Adapter<RecyclerViewListAdapter.ListViewHolder> {private Context mContext ;//泛型是RecyclerView所需的Bean类private List<DateBean> mDateBeen ;//构造方法,一般需要接收两个参数 1.上下文 2.集合对象(包含了我们所需要的数据)public RecyclerViewListAdapter(Context context, List<DateBean> dateBeen) {mContext = context;mDateBeen = dateBeen;}//创建VIewHolder也就是创建出来一条Item,并把viewHolder(item)返回出去@Overridepublic RecyclerViewListAdapter.ListViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {//转换一个ViewHolder对象,决定了item的样式,参数1.上下文 2.XML布局资源 3.nullView itemView = View. inflate ( mContext , R.layout. list_item , null );//创建一个ViewHodler对象ListViewHolder listViewHolder = new ListViewHolder(itemView);//把ViewHolder传出去return listViewHolder;}//当ViewHolder和数据绑定是回调@Overridepublic void onBindViewHolder(RecyclerViewListAdapter.ListViewHolder holder, int position) {//从集合里拿对应的item的数据对象DateBean dateBean = mDateBeen .get(position);//给Holder里面的控件对象设置数据holder.setData(dateBean);}//决定RecyclerView有多少条item@Overridepublic int getItemCount() {//数据不为null,有几条数据就显示几条数据if ( mDateBeen != null && mDateBeen .size() > 0 ) {return mDateBeen .size();}return 0 ;}//自动帮我们写的ViewHolder,参数:View布局对象public class ListViewHolder extends RecyclerView.ViewHolder {private final ImageView mImageView ;private final TextView mTextView ;public ListViewHolder(View itemView) {super (itemView);mImageView = (ImageView) itemView.findViewById(R.id. item_list_icon );mTextView = (TextView) itemView.findViewById(R.id. item_list_name );}public void setData(DateBean data) {//给imageView设置图片数据mImageView .setImageResource(data. icon );//给TextView设置文本数据mTextView .setText(data. name );}}}
6.编写主类
package com.example.recyclerview_activity;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.Menu;import android.view.MenuItem;import android.widget.Toast;import com.example.recyclerview_activity.adapter.RecyclerViewListAdapter;import com.example.recyclerview_activity.menu.DateBean;import java.util.ArrayList;public class MainActivity extends AppCompatActivity {private RecyclerView mRecyclerVIew ;@Overrideprotected void onCreate(Bundle savedInstanceState) {super .onCreate(savedInstanceState);setContentView(R.layout. activity_main );//初始化控件mRecyclerVIew = (RecyclerView) findViewById(R.id. recyclerView );}//RecyclerView填充数据,实现ListView效果private void loadListDate(Boolean inversion, Boolean orientation) {//集合对象ArrayList<DateBean> dateBeanArrayList = new ArrayList<>();//给Bean类放数据,把装好数据的Bean类放到集合里for ( int i = 0 ; i < 20 ; i++) {//创建Bean类对象DateBean dateBean = new DateBean();//给benu类对象添加图片和信息dateBean. icon = R.mipmap. ic_launcher ;dateBean. name = "RecyclerViewList" + i;//把Bean类放入集合dateBeanArrayList.add(dateBean);}//创建适配器adapter对象 参数有两个1.上下文 2.数据加载集合RecyclerViewListAdapter recyclerViewadapter = new RecyclerViewListAdapter( this , dateBeanArrayList);//设置适配器mRecyclerVIew .setAdapter(recyclerViewadapter);//布局管理器所需参数:上下文LinearLayoutManager linearLayoutManager = new LinearLayoutManager( this );//通过布局管理器可以控制条目排列的顺序 true反向显示 false正常显示(默认)linearLayoutManager.setReverseLayout(inversion);//设置RecycleView显示的方向是水平还是垂直//LinearLayoutManager.HORIZONTAL水平 LinearLayoutManager.VERTICAL默认垂直// 三元运算符linearLayoutManager.setOrientation(orientation ? LinearLayoutManager. VERTICAL : LinearLayoutManager. HORIZONTAL );//设置布局管理器, 参数linearLayoutManager对象mRecyclerVIew .setLayoutManager(linearLayoutManager);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {//加载布局使用菜单特有方法,getMenuInflate对象//参数1.菜单显示的布局 2.固定MenugetMenuInflater().inflate(R.menu. menu_main , menu);return true ;}//菜单按钮点击事件处理@Overridepublic boolean onOptionsItemSelected(MenuItem item) {int itemId = item.getItemId();if (itemId == R.id. action_ListView_noraml ) {//标准显示(垂直)loadListDate( false , true );Toast. makeText (MainActivity. this , "成功" , Toast. LENGTH_SHORT ).show();return true ;} //List垂直反向显示else if (itemId == R.id. action_ListView_vertical_reverse ) {loadListDate( true , true );} //List水平显示else if (itemId == R.id. action_ListView_horizontal ) {loadListDate( false , false );} //List水平反向else if (itemId == R.id. action_ListView_horizontal_reverse ) {loadListDate( true , false );}return super .onOptionsItemSelected(item);}}