XamarinAndroid_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。