详解分别用Kotlin和java写RecyclerView的示例

本文介绍了分别用kotlin和java写recyclerview的示例，分享给大家，具体如下：

java：跟一般的写法一样，增加了按钮响应

mainactivity：

public class mainactivity extends appcompatactivity implements recycleradapter.onitemclicklistener{
    private recyclerview mrecyclerview;
    private recyclerview.layoutmanager mlayoutmanager;
    private recycleradapter mrecycleradapter;
    private arraylistlist;

    @override
    protected void oncreate(bundlesaved instancestate) {
        super.oncreate(savedinstancestate);
        setcontentview(r.layout.activity_main);
        recycleritem item;
        list = new arraylist<>();
        item = new recycleritem();
        item.setname("no."+0);
        list.add(item);
        mrecyclerview = findviewbyid(r.id.recyclerview);
        mrecycleradapter = new recycleradapter(this,list);
        mrecycleradapter.setonitemclicklistener(this);
        // 竖直方向的网格样式，每行一个item
        mlayoutmanager=new gridlayoutmanager(this,3,orientationhelper.vertical,false);
        // 设置布局管理器
        mrecyclerview.setlayoutmanager(mlayoutmanager);
        // 设置adapter
        mrecyclerview.setadapter(mrecycleradapter);
        // 设置item添加和移除的动画
        mrecyclerview.setitemanimator(newdefaultitemanimator());
    }
    //adapter的按钮点击事件
    @override
    public void onitemcontentclick(viewview,intposition) {
        //点击最后一个按钮增加一个item
        if(position == list.size()-1) {
          recycleritemitem=newrecycleritem();
          item.setname("no."+(position+1));
          list.add(0,item);
          //更新recyclerview
          mrecycleradapter.updatedata(list);
        }else{
          toast.maketext(this,"no."+position,toast.length_short).show();
        }
    }
}

adapter：

public class recycleradapter extends recyclerview.adapter{
  private arraylist mdata;
  private context mcontext;
  private onitemclicklistener onitemclicklistener;
  public void setonitemclicklistener(onitemclicklistener listener) {
    this.onitemclicklistener = listener;
  }
  public recycleradapter(context mcontext,arraylist mdata){
    this.mdata = mdata;
    this.mcontext = mcontext;
  }

  //刷新整个list
  public void updatedata(arraylist data) {
    this.mdata = data;
    notifydatasetchanged();
  }

  //刷新局部list
  public void updatedataitem(arraylist data, int itemnm) {
    this.mdata = data;
    notifyitemchanged(itemnm);
  }

  @override
  public view holder oncreateviewholder(viewgroup parent, int viewtype) {
    view v = layoutinflater.from(parent.getcontext()).inflate(r.layout.recycler_item, parent, false);
    viewholder viewholder = new viewholder(v);
    return viewholder;
  }

  @override
  public void onbindviewholder(final viewholder holder, int position) {
    holder.btn.settext(mdata.get(position).getname());
    holder.btn.setonclicklistener(newview.onclicklistener() {
      @override
      public void onclick(view v) {
        if(onitemclicklistener != null) {
          int pos = holder.getlayoutposition();
          onitemclicklistener.onitemcontentclick(holder.itemview, pos);
        }
      }
    });
  }

  @override
  public int getitemcount() {
    return mdata == null ? 0 : mdata.size();
  }

  public static class viewholder extends recyclerview.viewholder{
    button btn;
    public viewholder(view itemview) {
      super(itemview);
      btn = itemview.findviewbyid(r.id.recycle_name);
    }
  }

  public interface onitemclicklistener{
    void onitemcontentclick(view view, int position);
  }
}

recycleritem:

public class recycleritem{
  string name;
  public string getname() {
    return name;
  }
  public void setname(string name) {
    this.name = name;
  }

activity_main:

<android.support.v7.widget.recyclerview
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context="com.tudou.recycleviewdemo.mainactivity">

  <android.support.v7.widget.recyclerview
    android:id="@+id/recyclerview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#00000000"
    android:paddingbottom="5dip">
  </android.support.v7.widget.recyclerview>
</android.support.constraint.constraintlayout>

recycler_item:

<relativelayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="100dp"
  android:layout_height="100dp">
  <button
    android:id="@+id/recycle_name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerinparent="true"
    android:text="no.1"/>
</relativelayout>

kotlin:语法略有不同，recyclerview调用类似

mainactivity：

class mainactivity : appcompatactivity(), mainadapter.itemclick{
  val items : mutablelist = arraylist()
  var mainadapter : mainadapter ?= null
  override fun oncreate(savedinstancestate:bundle?) {
    super.oncreate(savedinstancestate)
    setcontentview(r.layout.activity_main)
    //添加一个item
    var item : recycleritem
    item = recycleritem()
    item.name = "no."+0
    items.add(item)
    val recyclerview = findviewbyid(r.id.recyclerview) as recyclerview
    recyclerview.layoutmanager = gridlayoutmanager(this, 3, orientationhelper.vertical, false)
    mainadapter=mainadapter(items, this)
    mainadapter!!.setitemclicklistener(this)
    recyclerview.adapter = mainadapter
    recyclerview.itemanimator = defaultitemanimator()
  }

  //adapter的按钮点击事件
  override fun onitemclick(v : view, position : int) {
    if(position == items.size - 1) {
      val item = recycleritem()
      item.name = "no." + (position + 1)
      items.add(0, item)
      //更新数据
      mainadapter!!.updatedata(items)
    }else{
      toast.maketext(this,items.get(position).name, toast.length_short).show()
    }
  }
}

mainadapter：

class mainadapter : recyclerview.adapter{
  var items : list? = null
  var context : context ?= null
  var itemclick : itemclick ?= null
  constructor(items : list, context : context){
    this.items = items
    this.context = context
  }
  fun setitemclicklistener(itemclick : itemclick){
    this.itemclick = itemclick
  }
  fun updatedata(items : list){
    this.items = items
    notifydatasetchanged()
  }
  override fun onbindviewholder(holder : viewholder?, position : int) {
    var name=items!!.get(position).name
    if(holder != null) {
      holder.textname.settext(name)
      holder.textname.setonclicklistener(view.onclicklistener{
        if(itemclick != null) {
          itemclick!!.onitemclick(holder.itemview, position)
        }
      })
    }
  }
  override fun getitemcount():int{
    return items!!.size
  }
  override fun oncreateviewholder(parent : viewgroup?, viewtype : int) : viewholder{
    val v = layoutinflater.from(parent!!.context).inflate(r.layout.recycler_item, parent, false) as relativelayout
    val holder = viewholder(v)
    return holder
  }

  class viewholder(itemview : view?) : recyclerview.viewholder(itemview) {
    var textname : textview = itemview!!.findviewbyid(r.id.recycle_name) as textview
  }

  interface itemclick{
    fun onitemclick(v : view, position : int);
  }
}

recycleritem：

class recycleritem{
  var name : string = ""
    get
    set
}

activity_main:

<android.support.constraint.constraintlayout
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context="com.tudo.kotlintdemo.mainactivity">
  <android.support.v7.widget.recyclerview
    android:id="@+id/recyclerview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#00000000"
    android:paddingbottom="5dip">
  </android.support.v7.widget.recyclerview>
</android.support.constraint.constraintlayout>

recycler_item:

<relativelayout>
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="100dp"
  android:layout_height="100dp">
  <button
    android:id="@+id/recycle_name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerinparent="true"
    android:text="no.1"/>
</relativelayout>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。