Android的RecyclerView列表加载更多

用最简单简洁的方式做出目标效果
如果有什么不好的地方希望大佬在评论区指出！

本次练习项目是用一个开源的API做了一个图片APP，滑动到底部会触发加载更多

布局方面

main里面放入一个RecyclerView

创建一个item布局来作为列表，这个布局根据自己的需求来添加，我这里用卡片布局放了一个图片控件

java方面

使用到的依赖

    implementation 'com.github.bumptech.glide:glide:4.11.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.11.0'
    implementation 'com.google.code.gson:gson:2.8.6'
    implementation 'com.android.volley:volley:1.1.1'

创建一个bean类

这个是API那边提供的，然后用插件导入生成的

package com.sakura.testvolley.bean;

import java.util.List;

public class PhotoBean {
   
    
    

    private int total;
    private int totalHits;
    private List<HitsBean> hits;

    public int getTotal() {
   
    
    
        return total;
    }

    public void setTotal(int total) {
   
    
    
        this.total = total;
    }

    public int getTotalHits() {
   
    
    
        return totalHits;
    }

    public void setTotalHits(int totalHits) {
   
    
    
        this.totalHits = totalHits;
    }

    public List<HitsBean> getHits() {
   
    
    
        return hits;
    }

    public void setHits(List<HitsBean> hits) {
   
    
    
        this.hits = hits;
    }

    public static class HitsBean {
   
    
    
      
        private int id;
        private String pageURL;
        private String type;
        private String tags;
        private String previewURL;
        private int previewWidth;
        private int previewHeight;
        private String webformatURL;
        private int webformatWidth;
        private int webformatHeight;
        private String largeImageURL;
        private int imageWidth;
        private int imageHeight;
        private int imageSize;
        private int views;
        private int downloads;
        private int favorites;
        private int likes;
        private int comments;
        private int user_id;
        private String user;
        private String userImageURL;

        public int getId() {
   
    
    
            return id;
        }

        public void setId(int id) {
   
    
    
            this.id = id;
        }

        public String getPageURL() {
   
    
    
            return pageURL;
        }

        public void setPageURL(String pageURL) {
   
    
    
            this.pageURL = pageURL;
        }

        public String getType() {
   
    
    
            return type;
        }

        public void setType(String type) {
   
    
    
            this.type = type;
        }

        public String getTags() {
   
    
    
            return tags;
        }

        public void setTags(String tags) {
   
    
    
            this.tags = tags;
        }

        public String getPreviewURL() {
   
    
    
            return previewURL;
        }

        public void setPreviewURL(String previewURL)