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。