学步园

LayoutAnimationController的作用

1.为一个layout里面的控件，或ViewGroup里面的控件设置动画效果的类
2.每个控件设置动画一样
3.指定时间显示一帧
4.既可以在xml文件中配置，也可以在代码中实现

下面演示使用该对象实现一个2s淡入的动画效果。

具体使用步骤:

1)xml文件中配置LayoutAnimationController
  res/anim/layout_anim.xml

<?xml version="1.0" encoding="utf-8"?>
<layoutAnimation xmlns:android="http://schemas.android.com/apk/res/android"
    android:delay="2"
    android:animationOrder="normal"

    android:animation="@anim/alpha" />

2)还需要个动画配置文件
res/anim/alpha.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/accelerate_interpolator"
    android:shareInterpolator="true">

    <alpha
        android:fromAlpha="0.0"
        android:toAlpha="1.0"
        android:duration="2000" />

</set>

3. 布局文件中使用ListView

layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <ListView
        android:id="@id/android:list"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:scrollbars="vertical"
        />
    <Button
        android:id="@+id/btn_show"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="显示列表" />

</LinearLayout>

4.配置列表的样式文件:

layout/other.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent" android:layout_height="fill_parent"
    android:orientation="horizontal" android:paddingLeft="10dip"
    android:paddingRight="10dip" android:paddingTop="1dip"
    android:paddingBottom="1dip">
    <TextView android:id="@+id/name" android:layout_width="180dip"
        android:layout_height="30dip" android:textSize="5pt"
        android:singleLine="true" />
    <TextView android:id="@+id/age" android:layout_width="fill_parent"
        android:layout_height="fill_parent" android:textSize="5pt"
        android:singleLine="true"/>
</LinearLayout>

5.activity中的代码:

package com.example.layoutanimationctrl;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import android.app.ListActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.LayoutAnimationController;
import android.widget.Button;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class MainActivity extends ListActivity {

    private Button btn_show = null;
    private ListView list_view = null;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        btn_show = (Button)findViewById(R.id.btn_show);
        list_view = getListView();
        
        btn_show.setOnClickListener(new OnClickListener(){

            @Override
            public void onClick(View v) {
                System.out.println("you click button!");
                list_view.setAdapter(buildAdapter());
                
                // 这段代码演示没有layout_anim_ctl.xml文件中，在代码中使用LayoutAnimationControl播放动画效果
                /* Animation animation = AnimationUtils.loadAnimation(MainActivity.this, R.anim.alpha);
                LayoutAnimationController lac = new LayoutAnimationController(animation);
                list_view.setLayoutAnimation(lac);*/
            }
        });
    }
    
    // 用于填充listView的数据
    private ListAdapter buildAdapter(){    
        
        List<HashMap<String,String>> list = new ArrayList<HashMap<String, String>>();
        
        HashMap<String,String> stu1 = new HashMap<String, String>();
        stu1.put("name", "张三");
        stu1.put("age", "23");
        
        HashMap<String,String> stu2 = new HashMap<String, String>();
        stu2.put("name", "张4");
        stu2.put("age", "24");
        
        list.add(stu1);
        list.add(stu2);
        
        SimpleAdapter adapter = new SimpleAdapter(this,
                list, R.layout.other,
                new String[]{"name","age"},
                new int[]{R.id.name, R.id.age});
        
        return adapter;
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}