XamarinAndroid组件教程RecylerView动画组件使用动画(3)

（8）打开Main.axml文件，构建主界面。代码如下：

 android:orientation="vertical"

 android:layout_width="match_parent"

 android:layout_height="match_parent">

 android:id="@+id/tool_bar"

 android:layout_width="match_parent"

 android:layout_height="wrap_content"

 android:background="#3DC49D"

 android:minHeight="?attr/actionBarSize">

 android:layout_width="match_parent"

 android:layout_height="wrap_content">

 android:id="@+id/del"

 android:layout_width="wrap_content"

 android:layout_height="wrap_content"

 android:layout_alignParentRight="true"

 android:layout_centerInParent="true"

 android:background="?attr/selectableItemBackground"

 android:padding="10dp"

 android:text="DEL"/>

 android:id="@+id/add"

 android:layout_width="wrap_content"

 android:layout_height="wrap_content"

 android:layout_toLeftOf="@id/del"

 android:layout_centerInParent="true"

 android:background="?attr/selectableItemBackground"

 android:padding="10dp"

 android:text="ADD"/>

 

 android:id="@+id/list"

 android:layout_width="match_parent"

 android:layout_height="match_parent"/>

（9）打开MainActivity.cs文件，设置RecylerView子元素添加和删除时的动画效果。代码如下：

using Android.App;

using Android.Widget;

using Android.OS;

using Android.Support.V7.Widget;

using System.Linq;

using RecyclerViewAnimators.Animators;

using Android.Support.V7.App;

namespace RecylerViewAnimatorsItemAnimator

{

 [Activity(Label = "RecylerViewAnimatorsItemAnimator", MainLauncher = true, Icon = "@mipmap/icon", Theme = "@style/AppTheme")]

 public class MainActivity : AppCompatActivity

 {

 static readonly string[] data = {

 "Apple", "Ball", "Camera", "Day", "Egg", "Foo", "Google", "Hello", "Iron", "Japan", "Coke",

 "Dog", "Cat", "Yahoo", "Sony", "Canon", "Fujitsu", "USA", "Nexus", "LINE", "Haskell", "C++",

 "Java", "Go", "Swift", "Objective-c", "Ruby", "PHP", "Bash", "ksh", "C", "Groovy", "Kotlin",

 "Chip", "Japan", "U.S.A", "San Francisco", "Paris", "Tokyo", "Silicon Valley", "London",

 "Spain", "China", "Taiwan", "Asia", "New York", "France", "Kyoto", "Android", "Google", "C#",

 "iPhone", "iPad", "iPod", "Wasabeef", "Xamarin", "South Africa", "Cape Town", "Microsoft"

 };

 protected override void OnCreate(Bundle savedInstanceState)

 {

 base.OnCreate(savedInstanceState);

 SetContentView(Resource.Layout.Main);

 var toolbar = FindViewById(Resource.Id.tool_bar);

 SetSupportActionBar(toolbar);

 SupportActionBar.SetDisplayShowTitleEnabled(false);

 var recyclerView = FindViewById(Resource.Id.list);

 recyclerView.SetLayoutManager(new LinearLayoutManager(this)); //设置布局管理

 var datalist = data.ToList();

 var adapter = new DataAdapter(this, datalist);

 recyclerView.SetAdapter(adapter); //设置适配器

 recyclerView.SetItemAnimator(new FlipInLeftYAnimator()); //设置动画效果

 //添加子元素

 FindViewById(Resource.Id.add).Click += (sender, e) => {

 adapter.Add("newly added item", 1);

 };

 //删除子元素

 FindViewById(Resource.Id.del).Click += (sender, e) => {

 adapter.Remove(1);

 };

 }

 }

}

运行程序后，初始状态如图1.1所示。轻拍Add按钮，实现子元素的添加，在添加子元素的时候会伴有指定动画效果，如图1.2所示。轻拍DEL按钮，实现子元素的删除，在子元素删除的过程中也会伴有指定的动画效果。

图1.1 初始状态 图1.2 添加数据