Android_Gallery

xml布局

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     tools:context="com.example.android.gallery.MainActivity" >

     <Gallery
         android:id="@+id/gallery"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"/>
     <ImageSwitcher
         android:id="@+id/is"
         android:layout_width="match_parent"
         android:layout_height="0dp"
         android:layout_weight="1"
        />
 </LinearLayout>

自定义适配器：

 package com.example.android.gallery;

 import android.content.Context;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.BaseAdapter;
 import android.widget.Gallery;
 import android.widget.ImageView;
 import android.widget.ImageView.ScaleType;

 public class MyAdapter extends BaseAdapter {
     private int[] res;
     private Context context;

     public MyAdapter(int[] res, Context context) {
         this.res = res;
         this.context = context;
     }

     @Override
     public int getCount() {
         // TODO Auto-generated method stub
         return Integer.MAX_VALUE;//设置数量为整型的最大值，使图片循环播放
     }

     @Override
     public Object getItem(int position) {
         // TODO Auto-generated method stub
         return res[position];
     }

     @Override
     public long getItemId(int position) {
         // TODO Auto-generated method stub
         return position;
     }

     @Override
     public View getView(int position, View convertView, ViewGroup parent) {
         ImageView image = new ImageView(context);
         image.setBackgroundResource(res[position%res.length]);//设置背景图片无限循环
         image.setLayoutParams(new Gallery.LayoutParams(400, 300));//设置缩略图的大小
         image.setScaleType(ScaleType.FIT_XY);//设置按比例缩放
         return image;
     }

 }

MainActivity类：

 package com.example.android.gallery;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.animation.Animation;
 import android.view.animation.AnimationUtils;
 import android.widget.AdapterView;
 import android.widget.AdapterView.OnItemSelectedListener;
 import android.widget.Gallery;
 import android.widget.ImageSwitcher;
 import android.widget.ImageView;
 import android.widget.ImageView.ScaleType;
 import android.widget.ViewSwitcher.ViewFactory;
 /**
  * ImageSwitcher:和ImageView的功能类似，都适用与显示图片，
  *         区别：ImageSwitcher的效果更炫，它可以指定图片切换的动画效果
  *
  * ImageSwticher可以粗略理解为ImageView的选择器，需要设置ViewFactory，
  * 一般来说，会把ViewFactory的makeView()方法，返回ImageView。
  * @author Administrator
  *
  */
 public class MainActivity extends Activity implements ViewFactory,OnItemSelectedListener{
     //准备数据源
     private int[] res = {R.drawable.item1,R.drawable.item2,R.drawable.item3,R.drawable.item4,
                         R.drawable.item5,R.drawable.item6,R.drawable.item7,R.drawable.item8,
                         R.drawable.item9,R.drawable.item10,R.drawable.item11,R.drawable.item12};
     private Gallery gallery;
     private ImageSwitcher is;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         gallery = (Gallery) findViewById(R.id.gallery);
         //自定义适配器
         MyAdapter adapter = new MyAdapter(res,this);
         //为gallery设置适配器
         gallery.setAdapter(adapter);
         //为gallery设置监听器,用来监听Gallery选中的图片
         gallery.setOnItemSelectedListener(this);

         is = (ImageSwitcher) findViewById(R.id.is);
         is.setFactory(this);//为imageSwitcher设置视图工厂
         //为imageSwitcher设置动画效果
         is.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in));
         is.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_out));
     }
     @Override
     public View makeView() {
         // TODO Auto-generated method stub
         ImageView image = new ImageView(this);
         image.setScaleType(ScaleType.FIT_CENTER);//使图片按比例缩放并居中
         return image;
     }
     @Override
     public void onItemSelected(AdapterView<?> parent, View view, int position,
             long id) {
         // TODO Auto-generated method stub
         is.setBackgroundResource(res[position%res.length]);
     }
     @Override
     public void onNothingSelected(AdapterView<?> parent) {
         // TODO Auto-generated method stub

     }
 }