Android RecyclerView实现水平、垂直方向分割线

android recyclerview不像过去的listview那样随意的设置水平方向的分割线，如果要实现recyclerview的水平/垂直分割线，则需要继承自recyclerview.itemdecoration重写getitemoffsets方法，从而增加水平/垂直分割线。

写一个例子。

mainactivity.java：

package zhangphil.app;

import android.content.context;
import android.graphics.color;
import android.support.v7.app.appcompatactivity;
import android.os.bundle;
import android.support.v7.widget.recyclerview;
import android.support.v7.widget.staggeredgridlayoutmanager;
import android.view.view;
import android.view.viewgroup;
import android.widget.textview;

public class mainactivity extends appcompatactivity {

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

    recyclerview mrecyclerview = (recyclerview) findviewbyid(r.id.recyclerview);

    // 两列
    int spancount = 2;

    // staggeredgridlayoutmanager管理recyclerview的布局。
    staggeredgridlayoutmanager mlayoutmanager = new staggeredgridlayoutmanager(spancount, staggeredgridlayoutmanager.vertical);
    mrecyclerview.setlayoutmanager(mlayoutmanager);

    //为recyclerview增加分割线，水平和垂直方向都有。增加分割线值比如为32。
    recyclerviewitemdecoration decoration = new recyclerviewitemdecoration(32);
    mrecyclerview.additemdecoration(decoration);

    recyclerviewadapter madapter = new recyclerviewadapter(this);
    mrecyclerview.setadapter(madapter);
  }

  private class itemviewholder extends recyclerview.viewholder {
    private textview text;

    public itemviewholder(view itemview) {
      super(itemview);
      text = (textview) itemview.findviewbyid(android.r.id.text1);
      text.settextcolor(color.white);
    }
  }

  public class recyclerviewadapter extends recyclerview.adapter<itemviewholder> {
    private context context;

    public recyclerviewadapter(context context) {
      super();
      this.context = context;
    }

    @override
    public itemviewholder oncreateviewholder(viewgroup viewgroup, int viewtype) {
      view view = view.inflate(context, android.r.layout.simple_list_item_1, null);
      view.setbackgroundcolor(color.red);
      itemviewholder holder = new itemviewholder(view);
      return holder;
    }

    @override
    public void onbindviewholder(itemviewholder viewholder, int pos) {
      viewholder.text.settext(string.valueof(pos));
    }

    @override
    public int getitemcount() {
      return 15;
    }
  }
}

布局文件，很简单，就放一个recyclerview，注意背景颜色的设置：

<?xml version="1.0" encoding="utf-8"?>
<relativelayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:background="@android:color/holo_orange_light">

  <android.support.v7.widget.recyclerview
    android:id="@+id/recyclerview"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
  </android.support.v7.widget.recyclerview>

</relativelayout>

最关键的recyclerviewitemdecoration.java：

package zhangphil.app;

/**
 * created by phil on 2016/10/8.
 */

import android.graphics.rect;
import android.support.v7.widget.recyclerview;
import android.view.view;

/**
 * 为recyclerview增加间距
 * 预设2列，如果是3列，则左右值不同
 */
public class recyclerviewitemdecoration extends recyclerview.itemdecoration {
  private int space = 0;
  private int pos;

  public recyclerviewitemdecoration(int space) {
    this.space = space;
  }

  @override
  public void getitemoffsets(rect outrect, view view, recyclerview parent, recyclerview.state state) {

    outrect.top = space;

    //该view在整个recyclerview中位置。
    pos = parent.getchildadapterposition(view);

    //取模

    //两列的左边一列
    if (pos % 2 == 0) {
      outrect.left = space;
      outrect.right = space / 2;
    }

    //两列的右边一列
    if (pos % 2 == 1) {
      outrect.left = space / 2;
      outrect.right = space;
    }
  }
}

代码运行结果：

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。