Android ListView万能适配器实例代码

listview是开发中最常用的控件了，但是总是会写重复的代码，浪费时间又没有意义。

最近参考一些资料，发现一个万能listview适配器，代码量少，节省时间，总结一下分享给大家。

首先有一个自定义的adapter继承于baseadapter，下面是自定义的adapter，精华在getview()方法中

package com.example.mylistview.util;

import java.util.list;

import android.content.context;
import android.view.layoutinflater;
import android.view.view;
import android.view.viewgroup;
import android.widget.baseadapter;

public abstract class commonadapter<t> extends baseadapter {
 /**
  * 上下文
  */
 private context mcontext;
 /**
  * 实体类集合
  */
 private list<t> mdatas;
 private layoutinflater minflater;
 /**
  * 控件id
  */
 private int mlayoutid;

 public commonadapter(context context, list<t> datas, int layoutid) {
  this.mcontext = context;
  this.mdatas = datas;
  this.mlayoutid = layoutid;
  minflater = layoutinflater.from(context);
 }

 @override
 public int getcount() {
  // todo auto-generated method stub
  return mdatas.size();
 }

 @override
 public t getitem(int arg0) {
  // todo auto-generated method stub
  return mdatas.get(arg0);
 }

 @override
 public long getitemid(int arg0) {
  // todo auto-generated method stub
  return arg0;
 }

 @override
 public view getview(int arg0, view arg1, viewgroup arg2) {
  // todo auto-generated method stub
  viewholder holder = viewholder.get(mcontext, arg1, arg2, mlayoutid,
    arg0);
  convert(holder, getitem(arg0));

  return holder.getconvertview();
 }

 public abstract void convert(viewholder holder, t t);
}

以上的抽象方法convert(viewholder holder, t t)；就相当于以前通用代码中的

viewholder.mtextview = (textview) convertview .findviewbyid(r.id.id_tv_title);

viewholder.mtextview.settext(bean.getname());

找到控件的id再去设施settext等重复的代码方法中的参数viewholder holder, t t    holder就相当于以前通用代码中的viewholder，t就相当于一个自己定义的实体类bean。

以上代码中getview()方法中有一个viewholder是需要自己声明的，以下是代码以及详细注释：

package com.example.mylistview.util;

import android.content.context;
import android.graphics.bitmap;
import android.renderscript.type;
import android.util.sparsearray;
import android.view.layoutinflater;
import android.view.view;
import android.view.viewgroup;
import android.widget.imageview;
import android.widget.textview;

public class viewholder {
 /**
  * sparsearray类存放view集合
  */
 private sparsearray<view> mviews;
 /**
  * 
  */
 private int mposition;
 /**
  * 布局文件
  */
 private view mconvertview;

 public view getconvertview() {
  return mconvertview;
 }

 public viewholder(context context, viewgroup parent, int layoutid,
   int position) {
  this.mviews = new sparsearray<view>();
  this.mposition = position;
  this.mconvertview = layoutinflater.from(context).inflate(layoutid,
    parent, false);
  this.mconvertview.settag(this);
 }
 /**
  * 拿到一个viewholder对象
  * @param context
  * @param convertview
  * @param parent
  * @param layoutid
  * @param position
  * @return
  */
 public static viewholder get(context context, view convertview,
   viewgroup parent, int layoutid, int position) {
  if (null == convertview) {
   return new viewholder(context, parent, layoutid, position);
  } else {
   viewholder holder = (viewholder) convertview.gettag();
   holder.mposition = position;
   return holder;
  }
 }
 /**
  * 通过控件的id获取对应的控件，如果没有则加入views
  * @param viewid
  * @return
  */
 public <t extends view> t getview(int viewid) {
  view view = mviews.get(viewid);

  if (null == view) {
   view = mconvertview.findviewbyid(viewid);
   mviews.put(viewid, view);
  }

  return (t) view;
 }
 /**
  * 为textview设置字符串 
  * @param viewid
  * @param text
  * @return
  */
 public viewholder settext(int viewid, string text) {
  textview tv = getview(viewid);
  tv.settext(text);
  return this;
 }
 /** 
  * 为imageview设置图片 
  * 
  * @param viewid 
  * @param drawableid 
  * @return 
  */ 
 public viewholder setimageresource(int viewid, int drawableid) 
 { 
  imageview view = getview(viewid); 
  view.setimageresource(drawableid); 
  return this; 
 } 
 
 
 public int getposition() 
 { 
  return mposition; 
 } 
}

再写一个adapter继承于万能适配器commonadapter，还是要写一个自己的adapter,因为一个项目可能会有多个listview，但是每个的item元素，布局都会有所不同的，这个泪用来区分不同的listview与自己所对应的item.这个代码量较少完全可以写成内部类在activity.java中.

package com.example.mylistview.adapter;

import java.util.list;

import android.content.context;
import android.view.view;
import android.view.view.onclicklistener;
import android.widget.checkbox;

import com.example.mylistview.r;
import com.example.mylistview.domain.bean;
import com.example.mylistview.util.commonadapter;
import com.example.mylistview.util.viewholder;

public class myadapter extends commonadapter<bean> {

 public myadapter(context context, list<bean> datas, int layoutid) {
  super(context, datas, layoutid);
  // todo auto-generated constructor stub
 }

 @override
 public void convert(viewholder holder, final bean bean) {
  // todo auto-generated method stub
  holder.settext(r.id.tv_title, bean.gettitle())
    .settext(r.id.tv_desc, bean.getdesc())
    .settext(r.id.tv_time, bean.gettime())
    .settext(r.id.tv_phone, bean.getphone());
  /**
   * 防止checkbox混乱
   */
  final checkbox cbox = (checkbox)(holder.getview(r.id.cb));
  if (cbox != null)
  {
   cbox.setchecked(bean.ischecked());

   cbox.setonclicklistener(new onclicklistener()
   {
    @override
    public void onclick(view v)
    {
     bean.setchecked(cbox.ischecked());
    }
   });
  }
 }

}

优化之后用适配器的时候就简单多了下面是实体类,item和mainactivity.java中的代码：

实体类：

package com.example.mylistview.domain;

public class bean {
 private string title;
 private string desc;
 private string time;
 private string phone;
 private boolean ischecked;

 public boolean ischecked() {
  return ischecked;
 }

 public void setchecked(boolean ischecked) {
  this.ischecked = ischecked;
 }

 /**
  * @param title
  * @param desc
  * @param time
  * @param phone
  */
 public bean(string title, string desc, string time, string phone) {
  this.title = title;
  this.desc = desc;
  this.time = time;
  this.phone = phone;
 }

 public string gettitle() {
  return title;
 }

 public void settitle(string title) {
  this.title = title;
 }

 public string getdesc() {
  return desc;
 }

 public void setdesc(string desc) {
  this.desc = desc;
 }

 public string gettime() {
  return time;
 }

 public void settime(string time) {
  this.time = time;
 }

 public string getphone() {
  return phone;
 }

 public void setphone(string phone) {
  this.phone = phone;
 }

}

mainactivity.java：

重点代码：

参数有上下文，集合，和自己对应的item就可以了
 adapter = new myadapter(this, mdatas, r.layout.item);

package com.example.mylistview.ui;

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

import android.app.activity;
import android.content.intent;
import android.os.bundle;
import android.view.view;
import android.widget.adapterview;
import android.widget.adapterview.onitemclicklistener;
import android.widget.listview;

import com.example.mylistview.r;
import com.example.mylistview.adapter.myadapter;
import com.example.mylistview.domain.bean;

public class mainactivity extends activity {
 private listview listview;
 private list<bean> mdatas;
 /**
  * 适配器
  */
 private myadapter adapter;

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

 private void listener() {
  // todo auto-generated method stub
  listview.setonitemclicklistener(new onitemclicklistener() {

   @override
   public void onitemclick(adapterview<?> arg0, view arg1, int arg2,
     long arg3) {
    // todo auto-generated method stub
    startactivity(new intent(mainactivity.this, secondactivity.class));
   }
  });
 }

 private void initdata() {
  // todo auto-generated method stub
  mdatas = new arraylist<bean>();
  bean bean = new bean("android新技能 get",
    "android-打造万能的listview和gridview适配器", "2015-08-05", "10086");
  mdatas.add(bean);
  bean = new bean("捡到权志龙一个",
    "在星巴克捡到权志龙一个", "2015-08-06", "10086");
  mdatas.add(bean);
  bean = new bean("gettop一个",
    "在韩国首尔捡到top一个", "2015-08-07", "10086");
  mdatas.add(bean);
 
  adapter = new myadapter(this, mdatas, r.layout.item);
  listview.setadapter(adapter);
  
 }

 private void initview() {
  // todo auto-generated method stub
  listview = (listview) findviewbyid(r.id.listview);
 }

}

item布局：

<?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="wrap_content"
 android:padding="10dp" >

 <checkbox
  android:focusable="false"
  android:id="@+id/cb"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_alignparentright="true"
  android:layout_centerinparent="true" />

 <textview
  android:id="@+id/tv_title"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_margintop="10dp"
  android:singleline="true"
  android:text="android新技能 get" />

 <textview
  android:id="@+id/tv_desc"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_below="@id/tv_title"
  android:layout_margintop="10dp"
  android:layout_toleftof="@id/cb"
  android:maxlines="2"
  android:text="android-打造万能的listview和gridview适配器"
  android:textcolor="#898989" />

 <textview
  android:id="@+id/tv_time"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_below="@id/tv_desc"
  android:layout_margintop="10dp"
  android:text="2015-08-05"
  android:textcolor="#898989"
  android:textsize="12sp" />

 <textview
  android:id="@+id/tv_phone"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_alignparentright="true"
  android:layout_below="@id/tv_desc"
  android:layout_margintop="10dp"
  android:background="#20793d"
  android:maxlines="1"
  android:text="10086"
  android:padding="4dp"
  android:textcolor="#fff" />

</relativelayout>

效果图：

用这个去适配另一个不同的布局：

新布局的adapter一样继承自己的万能adapter:commonadapter

package com.example.mylistview.adapter;

import java.util.list;
import java.util.map;


import android.content.context;

import com.example.mylistview.r;
import com.example.mylistview.util.commonadapter;
import com.example.mylistview.util.viewholder;

public class secondadapter extends commonadapter<map<string, string>> {

 public secondadapter(context context, list<map<string, string>> datas,
   int layoutid) {
  super(context, datas, layoutid);
  // todo auto-generated constructor stub
 }

 @override
 public void convert(viewholder holder, map<string, string> t) {
  // todo auto-generated method stub
  holder.settext(r.id.tv_item2values, t.get("values"));
 }

}

activity.java代码：

package com.example.mylistview.ui;

import java.util.arraylist;
import java.util.hashmap;
import java.util.list;
import java.util.map;

import android.app.activity;
import android.os.bundle;
import android.widget.listview;

import com.example.mylistview.r;
import com.example.mylistview.adapter.myadapter;
import com.example.mylistview.adapter.secondadapter;

public class secondactivity extends activity {
 private listview listview_second;
 private secondadapter secondadapter;
 private list<map<string, string>> lists = new arraylist<map<string, string>>();

 @override
 protected void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  setcontentview(r.layout.activity_second);
  initview();
  initdata();
 }

 private void initdata() {
  // todo auto-generated method stub
  for (int i = 0; i < 4; i++) {
   map map = new hashmap<string, string>();
   map.put("values", "条目" + i);
   lists.add(map);
  }
  secondadapter = new secondadapter(this, lists, r.layout.item2);
  listview_second.setadapter(secondadapter);
 }

 private void initview() {
  // todo auto-generated method stub
  listview_second = (listview) findviewbyid(r.id.listview_second);
 }

}

item：

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="horizontal" >

 

 <textview
  android:id="@+id/tv_item2values"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="center"
  android:text="ffffff"
  android:layout_margin="16dp"
  android:gravity="center" />

</linearlayout>

效果图：

以上就是对android listview 的资料整理，希望能给大家带来帮助！