老婆保佑，代码无BUG

前言

本篇文章，其实很基础，也没什么难度，就是给自己查漏补缺，然后一点一点的积累，

引用

 compile 'com.android.support:recyclerview-v7:26.1.0'

一：Adapter的写法

之前记录过，请参考本篇文章


public class MyAdapter extends RecyclerView.Adapter {

    private ArrayList mData;

    public MyAdapter(ArrayList data) {
        this.mData = data;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.view_rv_item, parent, false);
        return new ViewHolder(v);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.mTv.setText(mData.get(position));
    }

    @Override
    public int getItemCount() {
        return mData == null ? 0 : mData.size();
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {

        TextView mTv;

        public ViewHolder(View itemView) {
            super(itemView);
            mTv = itemView.findViewById(R.id.item_tv);
        }
    }
}

二：布局管理器

1. LinearLayoutManager

线性管理器，支持横向、纵向。

（1）竖向

//竖向
mLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
//横向
mLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);

LinearLayoutManager.VERTICAL

对应XML

（2）横向

LinearLayoutManager.HORIZONTAL

2. GridLayoutManager

网格布局管理器

mLayoutManager = new GridLayoutManager(this, 4);
mRecyclerView.setLayoutManager(mLayoutManager);

网格布局管理器

3. StaggeredGridLayoutManager

瀑布就式布局管理器

MyStageAdapter myStageAdapter = new MyStageAdapter(getData());
mLayoutManager = new StaggeredGridLayoutManager(3, StaggeredGridLayoutManager.VERTICAL);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(myStageAdapter);

瀑布就式布局管理器

package com.allens.recyclerdemo;

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

/**
 * 描述:
 * 
 * Created by allens on 2018/1/4.
 */

public class MyStageAdapter extends RecyclerView.Adapter {

    private ArrayList mData;
    private List mHeights;

    public MyStageAdapter(ArrayList mData) {
        this.mData = mData;
        mHeights = new ArrayList();
        for (int i = 0; i < mData.size(); i++) {
            mHeights.add((int) (100 + Math.random() * 300));
        }
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View inflate = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_staggered_home, parent, false);
        return new ViewHolder(inflate);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.mTv.setText(mData.get(position));

        //设置高度
        ViewGroup.LayoutParams lp = holder.mTv.getLayoutParams();
        lp.height = mHeights.get(position);
        holder.mTv.setLayoutParams(lp);
    }

    @Override
    public int getItemCount() {
        return mData.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        TextView mTv;

        public ViewHolder(View itemView) {
            super(itemView);
            mTv = itemView.findViewById(R.id.id_num);
        }
    }
}

三：分割线

1. 添加Android自带的分割线

mRcv.addItemDecoration(new DividerItemDecoration(this,DividerItemDecoration.VERTICAL));

添加Android自带的分割线

2. 自定义分割线

打开DividerItemDecoration看看它的源码

  /**
     * Sets the {@link Drawable} for this divider.
     *
     * @param drawable Drawable that should be used as a divider.
     */
    public void setDrawable(@NonNull Drawable drawable) {
        if (drawable == null) {
            throw new IllegalArgumentException("Drawable cannot be null.");
        }
        mDivider = drawable;
    }

我们只需要调用这个方法，然后传入一个Drawable对象

 //添加自定义分割线
DividerItemDecoration divider = new DividerItemDecoration(this,DividerItemDecoration.VERTICAL);
divider.setDrawable(ContextCompat.getDrawable(this,R.drawable.rcv_divider));
mRcv.addItemDecoration(divider);

自定义分割线

当然还有一个继承ItemDecoration的方法可以实现，不过我感觉挺麻烦的，具体可以参考
张鸿洋 Android RecyclerView 使用完全解析体验艺术般的控件

这个有很多东西后期我会写一遍专门讲分割线的文章，先欠着，哈哈

四：ItemAnimator

插入删除的动画效果

mRecyclerView.setItemAnimator(new DefaultItemAnimator());