Xamarin-Android_BaseAdapter 简单的复用

Xamarin-Android_BaseAdapter 简单的复用

缘由:

　　本人是一枚 小菜 初学Xamarin-Android  正在学习ListView 控件 发现这个控件的自定义布局 用的那叫一个爽字了得。

但是每次用ListView的时候都要 继承一下BaseAdapter 这就不爽了。好气啊，我这个人非常的懒只好寻求改良之法。

　　写这篇博客在这里献丑甚是尴尬啊，还请园子里的诸位大咖多多指正。小弟不胜感激！【谢谢O(∩_∩)O哈！】

小弟学识浅薄仅仅做了以下的改良之处

• 抽取泛型 因为基本上的是大同小异的 只是 类型的不同 如这次是 Person 类型 下次可能就是 Student 类型的区别而已 所以就想到了泛型
• 将对 View 进行赋值的方法 使用委托进行替换。因为除了类型不同之外 也就这点不同了

下面是效果图 自己都感觉丑 丑哭了 (⊙o⊙)…

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代码奉上

ListItem的布局代码

 <?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:orientation="horizontal"

     android:layout_width="match_parent"

     android:layout_height="match_parent"

     android:minWidth="25px"

     android:minHeight="25px">

     <ImageView

         android:layout_width="89.5dp"

         android:layout_height="67.5dp"

         android:id="@+id/imgHard" />

     <LinearLayout

         android:orientation="vertical"

         android:minWidth="25px"

         android:minHeight="25px"

         android:layout_width="200dp"

         android:layout_height="67.5dp"

         android:id="@+id/linearLayout1">

         <TextView

             android:text="Large Text"

             android:textAppearance="?android:attr/textAppearanceLarge"

             android:layout_width="279.5dp"

             android:layout_height="wrap_content"

             android:id="@+id/txtName" />

         <TextView

             android:text="Small Text"

             android:textAppearance="?android:attr/textAppearanceSmall"

             android:layout_width="match_parent"

             android:layout_height="wrap_content"

             android:id="@+id/txtDesc"

             android:textSize="12dp" />

     </LinearLayout>

     <Button

         android:text="查看信息"

         android:layout_width="wrap_content"

         android:layout_height="67.5dp"

         android:id="@+id/button1" />

 </LinearLayout>

主界面的代码

 <?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:orientation="vertical"

     android:layout_width="match_parent"

     android:layout_height="match_parent">

     <ListView

         android:minWidth="25px"

         android:minHeight="25px"

         android:layout_width="match_parent"

         android:layout_height="match_parent"

         android:id="@+id/itemsPerson"

         android:divider="@android:color/white"

         android:dividerHeight="3dp"

         android:descendantFocusability="afterDescendants" />

 </LinearLayout>

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AllRoundBaseAdapter代码

 using System;

 using System.Collections.Generic;

 using System.Linq;

 using System.Text;

 using Android.App;

 using Android.Content;

 using Android.OS;

 using Android.Runtime;

 using Android.Views;

 using Android.Widget;

 namespace AdapterStudy_20170301

 {

     public class AllRoundAdapter<T> : BaseAdapter<T>

     {

         #region 全局变量

         /// <summary>

         /// 上下文

         /// </summary>

         public Activity MyContext { get; set; }

         /// <summary>

         /// 数据源

         /// </summary>

         public List<T> MyDataSource { get; set; }

         /// <summary>

         /// Item 布局资源

         /// </summary>

         public int LayoutSource { get; set; }

         /// <summary>

         /// 执行的委托

         /// </summary>

         Action<View, T> MyAction;

         #endregion

         /// <summary>

         /// 建立 AllRoundBaseAdapter

         /// </summary>

         /// <param name="actity">上下文</param>

         /// <param name="listDataSource">数据源</param>

         /// <param name="layoutSource">布局ID</param>

         /// <param name="action">为布局赋值用到的方法</param>

         public AllRoundAdapter(Activity actity, List<T> listDataSource, int layoutSource, Action<View, T> action)

         {

             this.MyContext = actity;

             this.MyDataSource = listDataSource;

             this.LayoutSource = layoutSource;

             this.MyAction = action;

         }

         public override T this[int position]

         {

             get

             {

                 return MyDataSource[position];

             }

         }

         public override int Count

         {

             get

             {

                 return this.MyDataSource.Count;

             }

         }

         public override long GetItemId(int position)

         {

             return position;

         }

         public override View GetView(int position, View convertView, ViewGroup parent)

         {

             T t = this.MyDataSource[position];

             View v = convertView;

             if (v == null)

             {

                 v = this.MyContext.LayoutInflater.Inflate(this.LayoutSource, null);

             }

             if (this.MyAction != null)

             {

                 this.MyAction.Invoke(v, t);

             }

             return v;

         }

     }

 }

MainActivity的代码

 using System;

 using Android.App;

 using Android.Content;

 using Android.Runtime;

 using Android.Views;

 using Android.Widget;

 using Android.OS;

 using System.Collections.Generic;

 using Javax.Crypto;

 namespace AdapterStudy_20170301

 {

     [Activity(Label = "AdapterStudy_20170301", MainLauncher = true, Icon = "@drawable/icon")]

     public class MainActivity : Activity

     {

         private ListView lvPerson;

         private List<Person> listPerson = new List<Person>();

         protected override void OnCreate(Bundle bundle)

         {

             base.OnCreate(bundle);

             // Set our view from the "main" layout resource

             SetContentView(Resource.Layout.Main);

             lvPerson = FindViewById<ListView>(Resource.Id.itemsPerson);

             //填充一些数据

             this.listPerson.Add(new Person("张飞", Resource.Drawable.person, "张翼德"));

             this.listPerson.Add(new Person("刘备", Resource.Drawable.person, "刘玄德"));

             this.listPerson.Add(new Person("关羽", Resource.Drawable.person, "关云长"));

             this.listPerson.Add(new Person("张飞", Resource.Drawable.person, "张翼德"));

             this.listPerson.Add(new Person("刘备", Resource.Drawable.person, "刘玄德"));

             this.listPerson.Add(new Person("关羽", Resource.Drawable.person, "关云长"));

             this.listPerson.Add(new Person("张飞", Resource.Drawable.person, "张翼德"));

             this.listPerson.Add(new Person("刘备", Resource.Drawable.person, "刘玄德"));

             this.listPerson.Add(new Person("张飞", Resource.Drawable.person, "张翼德"));

             this.listPerson.Add(new Person("刘备", Resource.Drawable.person, "刘玄德"));

             this.listPerson.Add(new Person("关羽", Resource.Drawable.person, "关云长"));

             this.listPerson.Add(new Person("关羽", Resource.Drawable.person, "关云长"));

             //设置表头表尾

             View header = this.LayoutInflater.Inflate(Resource.Layout.HeaderLayout, null);

             View footer = this.LayoutInflater.Inflate(Resource.Layout.FooterLayout, null);

             this.lvPerson.AddHeaderView(header);

             this.lvPerson.AddFooterView(footer);

             //使用泛型的Adapter 进行赋值

             lvPerson.Adapter = new AllRoundAdapter<Person>(this, listPerson, Resource.Layout.ListViewItemLayout,

                 (x, y) =>

                 {

                     x.FindViewById<TextView>(Resource.Id.txtName).Text = y.Name;

                     x.FindViewById<TextView>(Resource.Id.txtDesc).Text = y.Desc;

                     x.FindViewById<ImageView>(Resource.Id.imgHard).SetBackgroundResource(y.Image);

                 });

         }

     }

 }

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学识浅薄，请多多指正，多多关照！ 感觉自己好菜 掩面而逃。