RecyclerView增加和删除效果

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RecyclerView增加和删除效果,不多说，代码中有注释

这里用到的是 * recy_view.setItemAnimator(new DefaultItemAnimator());

一、代码目录结构

这里写图片描述

二、MainActivity中代码

import android.app.Activity;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.view.View;import android.widget.Button;import android.widget.Toast;import java.util.ArrayList;import java.util.List;public class MainActivity extends Activity implements View.OnClickListener{    private RecyclerView recy_view;    private List<String> data;    private ViewHoderAdaapters adaapters;    private Button add_but,rm_but;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        init();    }    private void init() {        add_but =  (Button) findViewById(R.id.add_but);        add_but.setOnClickListener(this);        rm_but =  (Button) findViewById(R.id.rm_but);        rm_but.setOnClickListener(this);        recy_view= (RecyclerView)findViewById(R.id.recy_view);        //默认列表        GridLayoutManager LM = new GridLayoutManager(this,4);        //横向滑动        recy_view.setLayoutManager(LM);        recy_view.setItemAnimator(new DefaultItemAnimator());        //样式二,对应类DividerItemDecoration02        recy_view.addItemDecoration(new DividerItemDecoration02(this,LinearLayoutManager.HORIZONTAL,R.drawable.style02));        initData();        adaapters = new ViewHoderAdaapters(MainActivity.this,data);        adaapters.setOnItemListener(new ViewHoderAdaapters.OnItemClickListener() {            public void onLongClick(int position) {                Toast.makeText(MainActivity.this,"您点击了第："+position+"个Item",Toast.LENGTH_SHORT).show();            }            public void onClick(int position) {                Toast.makeText(MainActivity.this,"您点击了第："+position+"个Item",Toast.LENGTH_SHORT).show();            }        });        recy_view.setAdapter(adaapters);    }    private void initData() {        data = new ArrayList<String>();        for (int i=0; i < 20; i++) {            data.add("我是熊大"+i);        }    }    @Override    public void onClick(View v) {        switch (v.getId()){            case R.id.add_but:                adaapters.addData(1);                break;            case R.id.rm_but:                adaapters.removeData(1);                break;        }    }}

三、适配器代码中代码

import android.content.Context;import android.support.v7.widget.RecyclerView;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.LinearLayout;import android.widget.TextView;import android.widget.Toast;import java.util.List;/** * Created by ENZ on 2016/10/15. */class ViewHoderAdaapters extends RecyclerView.Adapter {    private Context context;    private List<String> datas;    private LayoutInflater inflater;    private OnItemClickListener mOnItemClickListener;    //构造方法    public ViewHoderAdaapters(MainActivity mainActivity, List<String> data) {        this.context = mainActivity;        this.datas = data;        inflater = LayoutInflater.from(context);    }    //定义一个监听接口，里面有两个方法    public interface OnItemClickListener{        void onClick(int position);        void onLongClick(int position);    }    //给监听设置一个构造函数，用于main中调用    public void setOnItemListener(OnItemClickListener mOnItemClickListener) {        this.mOnItemClickListener = mOnItemClickListener;    }    @Override    //重写onCreateViewHolder方法，返回一个自定义的ViewHolder    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {        View view = inflater.inflate(R.layout.main_item,parent,false);        ViewHoders viewHoders = new ViewHoders(view);        return viewHoders;    }    @Override    //填充onCreateViewHolder方法返回的holder中的控件    public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position) {        ((ViewHoders) holder).tv.setText(datas.get(position));        if (mOnItemClickListener!=null) {            //直接给某个空间添加监听            ((ViewHoders) holder).li_layout.setOnClickListener(new View.OnClickListener() {                @Override                public void onClick(View v) {                    mOnItemClickListener.onClick(position);                }            });            //直接给某个空间添加长按监听            ((ViewHoders) holder).li_layout.setOnClickListener(new View.OnClickListener() {                @Override                public void onClick(View v) {                    mOnItemClickListener.onLongClick(position);                }            });        }    }    @Override    public int getItemCount() {        return datas.size();    }    //自定义ViewHolder,    /*    * RecylerView封装了viewholder的回收复用，也就是说RecylerView标准化了ViewHolder，编写Adapter面向的是ViewHolder而不再是View了    * */    class ViewHoders extends RecyclerView.ViewHolder{        private TextView tv;        private LinearLayout li_layout;        public ViewHoders(View itemView) {            super(itemView);            tv= (TextView) itemView.findViewById(R.id.textview);            li_layout= (LinearLayout) itemView.findViewById(R.id.li_layout);        }    }    //添加一个增加item数据的方法，posion代表你从主类中传过来的值，这个值对应你添加的item在列表中的位置    public void addData(int position) {        //保证列表没有数据时，首先添加        if(datas.size()==0){            datas.add(0, "我是熊大");        }else {            //更新列表            datas.add(position, "我是熊大....");            notifyItemInserted(position);            notifyItemRangeChanged(position,datas.size());        }    }    public void removeData(int position) {        //保证列表有数据，并且最少有一条        if(datas.size()<2&&datas.size()!=0){            datas.remove(0);            notifyDataSetChanged();        }else if(datas.size()==0){//当列表没有数据提示用户，免得造成系统崩溃            Toast.makeText(context,"搞毛啊，没数据了",Toast.LENGTH_SHORT).show();        }else{//更新列表            datas.remove(position);            notifyDataSetChanged();            notifyItemRemoved(position);            notifyItemRangeChanged(position,datas.size());        }    }}

四、分割线代码

import android.content.Context;import android.graphics.Canvas;import android.graphics.Rect;import android.graphics.drawable.Drawable;import android.support.v4.content.ContextCompat;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.View;/** * Created by ENZ on 2016/10/15. */public class DividerItemDecoration02 extends RecyclerView.ItemDecoration {    //获取布局的方向    public static final int HORIZONTAL = LinearLayoutManager.HORIZONTAL;    public static final int VERTICAL = LinearLayoutManager.VERTICAL;    //可以延长的    private Drawable mDivider;    private int mOrientation;    //方向的判断    private void setOrientation(int orientation) {        if (orientation != HORIZONTAL && orientation != VERTICAL) {            throw new IllegalArgumentException("你传递的方向参数好像有问题");        }        //方向赋值给对象mOrientation;        mOrientation = orientation;    }    /**     * 自定义分割线     *     * @param context     * @param orientation 列表方向     * @param drawableId  分割线图片     */    public DividerItemDecoration02(Context context, int orientation, int drawableId) {        mDivider = ContextCompat.getDrawable(context, drawableId);        setOrientation(orientation);    }    //重写onDraw（）方法。并且根据传递过来的方向来进行绘制分割线    @Override    public void onDraw(Canvas c, RecyclerView parent) {        if (mOrientation == VERTICAL) {            drawVertical(c, parent);        } else {            drawHorizontal(c, parent);        }    }    /**     * 绘制横向 item 分割线     * @param parent     */    private void drawHorizontal(Canvas c, RecyclerView parent) {        //左右的间距 ，left就是距离父类边界的距离，right同理        final int left = parent.getPaddingLeft()+10;        final int right = parent.getWidth() - parent.getPaddingRight()-10;        //获取item数据的长度        final int childCount = parent.getChildCount();        //循环绘制分割线        for (int i = 0; i < childCount; i++) {            //            final View child = parent.getChildAt(i);            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams();            final int top = child.getBottom() + params.bottomMargin;            final int bottom = top + mDivider.getIntrinsicHeight();            mDivider.setBounds(left, top, right, bottom);            mDivider.draw(c);        }    }    /**     * 绘制纵向 item 分割线     * @param parent     */    private void drawVertical(Canvas c, RecyclerView parent) {        //左右的间距 ，top就是距离父类顶边界的距离，bottom是距离父类底部的边界距离        final int top = parent.getPaddingTop();        final int bottom = parent.getHeight() - parent.getPaddingBottom();        final int childCount = parent.getChildCount();        //循环绘制分割线        for (int i = 0; i < childCount; i++) {            final View child = parent.getChildAt(i);            final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();            final int left = child.getRight() + params.rightMargin;            final int right = left + mDivider.getIntrinsicHeight();            mDivider.setBounds(left, top, right, bottom);            mDivider.draw(c);        }    }    /*    * 获取分割线尺寸    * getItemOffsets 中为 outRect 设置的4个方向的值，将被计算进所有 decoration 的尺寸中，而这个尺寸，被计入了 RecyclerView 每个 item view 的 padding 中    * */    public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) {        if (mOrientation == VERTICAL) {            //在这个地方，我们才获取            outRect.set(0, 0, 0,  mDivider.getIntrinsicWidth());        }else{            outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);        }    }}

五、布局和样式代码

main布局

?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:id="@+id/activity_main"    android:orientation="vertical"    android:layout_width="match_parent"    android:layout_height="match_parent">    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal">        <Button            android:id="@+id/add_but"            android:layout_width="match_parent"            android:layout_height="40dp"            android:layout_weight="1"            android:text="添加一条新数据"/>        <Button            android:id="@+id/rm_but"            android:layout_width="match_parent"            android:layout_height="40dp"            android:layout_weight="1"            android:text="删除一条新数据"/>    </LinearLayout>    <android.support.v7.widget.RecyclerView        android:id="@+id/recy_view"        android:layout_width="match_parent"        android:layout_height="wrap_content"         /></LinearLayout>

效果图：

item布局

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:id="@+id/activity_main"    android:orientation="vertical"    android:layout_width="wrap_content"    android:layout_height="wrap_content">    <LinearLayout        android:id="@+id/li_layout"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_margin="5dp"        android:orientation="vertical">        <TextView            android:id="@+id/textview"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:gravity="center"            android:text="我是熊大"/>        <ImageView            android:id="@+id/imgview"            android:layout_width="80dp"            android:layout_gravity="center_horizontal"            android:layout_height="60dp"            android:background="@drawable/xiong01"/>    </LinearLayout></LinearLayout>

效果图：
这里写图片描述

样式

<shape xmlns:android="http://schemas.android.com/apk/res/android"    android:shape="rectangle" >       <!-- 填充的颜色 -->       <solid android:color="#ED9800"/>      <!--  线条高度 -->      <size android:height="5dp" android:width="1dp"/></shape>

六、demo:http://download.csdn.net/detail/bobo8945510/9658281

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