android RecyclerView
引用
在项目的build.gradle添加依赖
compile 'com.android.support:recyclerview-v7:23.4.0'
recyclierview使用的基本方法
recyclerview.setadapter(); 添加适配器(必须)
recyclerview.setlayoutmanager(); 选择一种布局(必须)
recycleradapter.setheaderview(); 添加头布局
recycleradapter.setfooterview(); 添加底部布局
recyclerview.setitemanimator(new defaultitemanimator()); 添加默认动画
recyclerview.additemdecoration(); 添加分割线
layout manager布局管理器
1.三种布局管理器:
new linearlayoutmanager(this, linearlayoutmanager.vertical, false) 以垂直或者水平列表方式展示item,第三个参数是否颠倒数据显示
new gridlayoutmanager(this,4) 以网格方式展示item,第二个参数代表列数
new staggeredgridlayoutmanager(4, staggeredgridlayoutmanager.horizontal) 以瀑布流方式展示item,第一个参数代表列数
2.常用方法
canscrollhorizontally();//能否横向滚动 canscrollvertically();//能否纵向滚动 scrolltoposition(int position);//滚动到指定位置 setorientation(int orientation);//设置滚动的方向 getorientation();//获取滚动方向 findviewbyposition(int position);//获取指定位置的item view findfirstcompletelyvisibleitemposition();//获取第一个完全可见的item位置 findfirstvisibleitemposition();//获取第一个可见item的位置 findlastcompletelyvisibleitemposition();//获取最后一个完全可见的item位置 findlastvisibleitemposition();//获取最后一个可见item的位置
adapter适配器模板
recyclerview必须自定义适配器,并且自己创建事件监听,布局和数据的绑定顺序,每个item都会执行一遍:getiitemviewtype(绑定类型) > oncreateviewholder(选择布局类型) > onbindviewholder(绑定数据)
notifyiteminserted(position);插入一个item
notifyitemremoved(position); 移除一个item
notifyitemchanged(position) 刷新item
public class datarecycleradapter extends recyclerview.adapter<datarecycleradapter.myviewholder>{ private list<string> list; private context context; private list<integer> mheights; private static int type_title=0; private static int type_footer=1; private static int type_content =2; private view mheaderview; private view mfooterview; public datarecycleradapter(context context, list<string> list) { this.list=list; mheights = new arraylist<>(); this.context=context; } //根据不同的类型适应不用的布局 @override public myviewholder oncreateviewholder(viewgroup parent, int viewtype) { if(mheaderview != null && viewtype == type_title) { return new myviewholder(mheaderview); } if(mfooterview != null && viewtype == type_footer) { return new myviewholder(mfooterview); } return new myviewholder(layoutinflater.from(context).inflate(r.layout.options_item3,parent,false)); } //给item分布不同的类型 @override public int getitemviewtype(int position) { if (position == 0){ return type_title; }else if(position==list.size()){ return type_footer; }else{ return type_content; } } public view getheaderview() { return mheaderview; } //添加自定义的头部 public void setheaderview(view headerview) { mheaderview = headerview; notifyiteminserted(0); } public view getfooterview() { return mfooterview; } //添加自定义底部 public void setfooterview(view footerview) { mfooterview = footerview; notifyiteminserted(list.size()+1); } //主体布局 @override public void onbindviewholder(final myviewholder holder, int position) { if(getitemviewtype(position) != type_content) { return; } holder.textview.settext(list.get(position-1)); if (monitemclicklitener != null){ holder.itemview.setonclicklistener(new view.onclicklistener(){ @override public void onclick(view v){ int pos = holder.getlayoutposition(); monitemclicklitener.onitemclick(holder.itemview, pos); } }); holder.itemview.setonlongclicklistener(new view.onlongclicklistener(){ @override public boolean onlongclick(view v){ int pos = holder.getlayoutposition(); monitemclicklitener.onitemlongclick(holder.itemview, pos); return true; } }); } } //获取item总数 @override public int getitemcount() { if(mfooterview !=null){ return list.size()+1; }else { return list.size(); } } //监听器接口 public interface onitemclicklitener{ void onitemclick(view view, int position); void onitemlongclick(view view , int position); } private onitemclicklitener monitemclicklitener; public void setonmyitemclicklitener(onitemclicklitener monitemclicklitener) { this.monitemclicklitener = monitemclicklitener; } //头和底部的布局 class myviewholder extends recyclerview.viewholder { private textview textview; myviewholder(view itemview) { super(itemview); if (itemview == mheaderview||itemview == mfooterview){ return; } textview= (textview) itemview.findviewbyid(r.id.options_tv); textview.settext("uuu"); } } //模拟新增的数据 public void adddata(int position) { list.add(position, "insert 数据"); notifyiteminserted(position+1); toast.maketext(context,""+list.size(),toast.length_short).show(); } //移除一个布局 public void removedata(int position) { list.remove(position); notifyitemremoved(position); }
实例
private void initdatarecycleradapter(){ recycleradapter=new datarecycleradapter(this,mdata); //布局管理器 recyclerview.setlayoutmanager( new linearlayoutmanager(this, linearlayoutmanager.vertical, false)); //分割线 recyclerview.additemdecoration(new divideritemdecoration(this, divideritemdecoration.horizontal)); //使用默认动画 recyclerview.setitemanimator(new defaultitemanimator()); //不使用默认的布局类型,添加自定义头部布局 recycleradapter.setheaderview(layoutinflater.from(this).inflate(r.layout.options_title, recyclerview, false)); //不使用默认的布局类型,添加自定义底部布局 layoutinflater inflater= layoutinflater.from(this); view footerview = inflater.inflate(r.layout.options_footer, null); recycleradapter.setfooterview(footerview); //底部布局事件,增加一个item footerview.setonclicklistener(new view.onclicklistener() { @override public void onclick(view view) { toast.maketext(mainactivity.this,"展开",toast.length_short).show(); recycleradapter.adddata(mdata.size()); } }); recyclerview.setadapter(recycleradapter); recycleradapter.setonmyitemclicklitener(new datarecycleradapter.onitemclicklitener() { //item的点击事件,移除一个item @override public void onitemclick(view view, int position) { recycleradapter.removedata(position); toast.maketext(mainactivity.this,""+mdata.size(),toast.length_short).show(); } //item的长按事件,显示item下标 @override public void onitemlongclick(view view, int position) { toast.maketext(mainactivity.this,"第"+position+"个",toast.length_short).show(); } }); } //模拟数据源 private void adddata(){ mdata= new arraylist<>(); for (int i=1;i<20;i++) { mdata.add("数据"+i+"个"); } }
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