Android RecyclerView选择多个item的实现代码

模仿网易新闻客户端阅读偏好的频道选择，先看实现的页面：

直接上代码：

import android.content.res.resources;
import android.content.res.typedarray;
import android.os.bundle;
import android.support.v7.app.appcompatactivity;
import android.support.v7.widget.defaultitemanimator;
import android.support.v7.widget.gridlayoutmanager;
import android.support.v7.widget.recyclerview;
import android.support.v7.widget.helper.itemtouchhelper;
import android.util.log;
import android.util.sparsebooleanarray;
import android.view.view;

import java.util.arraylist;
import java.util.collections;
import java.util.list;

public class recyclerviewactivity extends appcompatactivity {
  private recyclerview recycler;
  private recycleradapter madapter;
  private list<prefercustomizablechannel> channels = new arraylist<>();
  private list<prefercustomizablechannel> channelsselected;

  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_recycler_view_acitivity);

    initdata();

    initui();

    findviewbyid(r.id.resultbtn).setonclicklistener(new view.onclicklistener() {
      @override
      public void onclick(view v) {
        int lens = channelsselected.size();
        for (int i =0 ; i < lens; i++) {
          prefercustomizablechannel customizablechannel = channelsselected.get(i);
          if (customizablechannel.isselected()) {
            log.i("recyclerviewactivity", "onclick: "+customizablechannel.tostring());
          }
        }
      }
    });
  }

  private void initdata() {
    resources resources = getresources();
    typedarray array = resources.obtaintypedarray(r.array.prefer_channel_icon);
    int len = array.length();
    string[] name = resources.getstringarray(r.array.prefer_channel_name);
    for (int i = 0; i < len; i++) {
      prefercustomizablechannel customizablechannel = new prefercustomizablechannel();
      customizablechannel.setchannel(name[i]);
      customizablechannel.setresid(array.getresourceid(i, 0));
      customizablechannel.setselected(false);
      customizablechannel.setid(i * 100);
      channels.add(customizablechannel);
    }
    array.recycle();
    channelsselected = channels;
  }

  private void initui() {
    recycler = (recyclerview) findviewbyid(r.id.recycler);
    final gridlayoutmanager manager = new gridlayoutmanager(this, 3);
    recycler.setlayoutmanager(manager);
    recycler.sethasfixedsize(true);
    recycler.setitemanimator(new defaultitemanimator());
    madapter = new recycleradapter(recyclerviewactivity.this, channels);
    recycler.setadapter(madapter);
    madapter.setclicklistener(new onrecyclerviewitemclicklistener() {
      @override
      public void onitemclick(view view, int position) {
        sparsebooleanarray selecteds = madapter.getselecteditem();
        int len = channels.size();
        for (int i = 0; i < len; i++) {
          if (selecteds.get(i)) {
            channelsselected.get(position).setselected(true);
          }
        }
      }
    });
  }
}

布局文件recyclerview横竖都是“match_parent”,否则在点击的时候gridview会自动上滑一段距离。

适配器的实现：

import android.support.v7.widget.recyclerview;
import android.util.sparsebooleanarray;
import android.view.layoutinflater;
import android.view.view;
import android.view.viewgroup;
import android.widget.imageview;
import android.widget.relativelayout;
import android.widget.textview;

import com.entity.prefercustomizablechannel;
import com.listener.onrecycleritemclicklistener;

import java.util.list;

import butterknife.bindview;
import butterknife.butterknife;

public class preferchanneladapter extends recyclerview.adapter<preferchanneladapter.preferchannelholder>{
  private list<prefercustomizablechannel> lists;
  private onrecycleritemclicklistener listener;
  private sparsebooleanarray selectlists = new sparsebooleanarray();

  public preferchanneladapter() {
  }

  public void setdatas(list<prefercustomizablechannel> lists) {
    this.lists = lists;
    notifydatasetchanged();
  }

  public void setonitemclicklistener(onrecycleritemclicklistener listener) {
    this.listener = listener;
  }

  @override
  public preferchannelholder oncreateviewholder(viewgroup parent, int viewtype) {
    view view = layoutinflater.from(parent.getcontext()).inflate(r.layout.prefer_channel_item, null);
    return new preferchannelholder(view);
  }

  @override
  public void onbindviewholder(final preferchannelholder holder, final int position) {
    prefercustomizablechannel channelitem = lists.get(position);
    holder.channelitemtv.settext(channelitem.getchannel());
    holder.channelitemimg.setimageresource(channelitem.getresid());
    if (!selectlists.get(position)) {
      holder.selectedmarkimg.setvisibility(view.gone);
    } else {
      holder.selectedmarkimg.setvisibility(view.visible);
    }
    holder.preferchannelitemlayout.setonclicklistener(new view.onclicklistener() {
      @override
      public void onclick(view view) {
        if (holder.selectedmarkimg.getvisibility() == view.gone) {
          holder.selectedmarkimg.setvisibility(view.visible);
          selectlists.put(position, true);
        } else if (holder.selectedmarkimg.getvisibility() == view.visible){
          holder.selectedmarkimg.setvisibility(view.gone);
          selectlists.put(position, false);
        }
        listener.onrecyclerclick(position);
      }
    });
  }

  @override
  public int getitemcount() {
    return lists.size();
  }

  public class preferchannelholder extends recyclerview.viewholder {
    @bindview(r.id.preferchannelitemlayout)
    relativelayout preferchannelitemlayout;
    @bindview(r.id.channelitemtv)
    textview channelitemtv;
    @bindview(r.id.channelitemimg)
    imageview channelitemimg;
    @bindview(r.id.selectedmarkimg)
    imageview selectedmarkimg;

    public preferchannelholder(view itemview) {
      super(itemview);
      butterknife.bind(this, itemview);
    }
  }

  public sparsebooleanarray getselecteditem() {
    return selectlists;
  }
}

顺便把item的布局也贴出来吧：

<?xml version="1.0" encoding="utf-8"?>
<relativelayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/preferchannelitemlayout"
  android:gravity="center"
  android:layout_gravity="center"
  android:layout_margintop="10dp"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content">
  <!--android:gravity="center"
  android:layout_gravity="center"-->
  <imageview
    android:id="@+id/channelitemimg"
    android:scaletype="centerinside"
    android:layout_width="68dp"
    android:layout_height="wrap_content"/>
  <textview
    android:id="@+id/channelitemtv"
    android:gravity="center"
    android:layout_marginleft="20dp"
    android:layout_marginright="20dp"
    android:layout_marginbottom="20dp"
    android:layout_margintop="8dp"
    android:layout_below="@id/channelitemimg"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />
  <imageview
    android:id="@+id/selectedmarkimg"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centervertical="true"
    android:visibility="gone"
    android:layout_alignright="@id/channelitemimg"
    android:src="@mipmap/prefer_selected"/>
</relativelayout>

其他注意的地方：

sparebooleanarrary.size()返回的是已经设置为true的长度，比如选择了一个则返回1，选择了10则返回10，但在选择了10后去掉一个的时候，size()返回的并不是9，而依然是10，这点注意，所以在遍历的时候并没有使用使用size()取长度。

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。