Android_Gallery

xml布局

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical"
 6     tools:context="com.example.android.gallery.MainActivity" >
 7
 8     <Gallery
 9         android:id="@+id/gallery"
10         android:layout_width="match_parent"
11         android:layout_height="wrap_content"/>
12     <ImageSwitcher
13         android:id="@+id/is"
14         android:layout_width="match_parent"
15         android:layout_height="0dp"
16         android:layout_weight="1"
17        />
18 </LinearLayout>

自定义适配器：

 1 package com.example.android.gallery;
 2
 3 import android.content.Context;
 4 import android.view.View;
 5 import android.view.ViewGroup;
 6 import android.widget.BaseAdapter;
 7 import android.widget.Gallery;
 8 import android.widget.ImageView;
 9 import android.widget.ImageView.ScaleType;
10
11 public class MyAdapter extends BaseAdapter {
12     private int[] res;
13     private Context context;
14
15     public MyAdapter(int[] res, Context context) {
16         this.res = res;
17         this.context = context;
18     }
19
20     @Override
21     public int getCount() {
22         // TODO Auto-generated method stub
23         return Integer.MAX_VALUE;//设置数量为整型的最大值，使图片循环播放
24     }
25
26     @Override
27     public Object getItem(int position) {
28         // TODO Auto-generated method stub
29         return res[position];
30     }
31
32     @Override
33     public long getItemId(int position) {
34         // TODO Auto-generated method stub
35         return position;
36     }
37
38     @Override
39     public View getView(int position, View convertView, ViewGroup parent) {
40         ImageView image = new ImageView(context);
41         image.setBackgroundResource(res[position%res.length]);//设置背景图片无限循环
42         image.setLayoutParams(new Gallery.LayoutParams(400, 300));//设置缩略图的大小
43         image.setScaleType(ScaleType.FIT_XY);//设置按比例缩放
44         return image;
45     }
46
47 }

MainActivity类：

 1 package com.example.android.gallery;
 2
 3 import android.app.Activity;
 4 import android.os.Bundle;
 5 import android.view.Menu;
 6 import android.view.MenuItem;
 7 import android.view.View;
 8 import android.view.animation.Animation;
 9 import android.view.animation.AnimationUtils;
10 import android.widget.AdapterView;
11 import android.widget.AdapterView.OnItemSelectedListener;
12 import android.widget.Gallery;
13 import android.widget.ImageSwitcher;
14 import android.widget.ImageView;
15 import android.widget.ImageView.ScaleType;
16 import android.widget.ViewSwitcher.ViewFactory;
17 /**
18  * ImageSwitcher:和ImageView的功能类似，都适用与显示图片，
19  *         区别：ImageSwitcher的效果更炫，它可以指定图片切换的动画效果
20  *
21  * ImageSwticher可以粗略理解为ImageView的选择器，需要设置ViewFactory，
22  * 一般来说，会把ViewFactory的makeView()方法，返回ImageView。
23  * @author Administrator
24  *
25  */
26 public class MainActivity extends Activity implements ViewFactory,OnItemSelectedListener{
27     //准备数据源
28     private int[] res = {R.drawable.item1,R.drawable.item2,R.drawable.item3,R.drawable.item4,
29                         R.drawable.item5,R.drawable.item6,R.drawable.item7,R.drawable.item8,
30                         R.drawable.item9,R.drawable.item10,R.drawable.item11,R.drawable.item12};
31     private Gallery gallery;
32     private ImageSwitcher is;
33     @Override
34     protected void onCreate(Bundle savedInstanceState) {
35         super.onCreate(savedInstanceState);
36         setContentView(R.layout.activity_main);
37         gallery = (Gallery) findViewById(R.id.gallery);
38         //自定义适配器
39         MyAdapter adapter = new MyAdapter(res,this);
40         //为gallery设置适配器
41         gallery.setAdapter(adapter);
42         //为gallery设置监听器,用来监听Gallery选中的图片
43         gallery.setOnItemSelectedListener(this);
44
45         is = (ImageSwitcher) findViewById(R.id.is);
46         is.setFactory(this);//为imageSwitcher设置视图工厂
47         //为imageSwitcher设置动画效果
48         is.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in));
49         is.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_out));
50     }
51     @Override
52     public View makeView() {
53         // TODO Auto-generated method stub
54         ImageView image = new ImageView(this);
55         image.setScaleType(ScaleType.FIT_CENTER);//使图片按比例缩放并居中
56         return image;
57     }
58     @Override
59     public void onItemSelected(AdapterView<?> parent, View view, int position,
60             long id) {
61         // TODO Auto-generated method stub
62         is.setBackgroundResource(res[position%res.length]);
63     }
64     @Override
65     public void onNothingSelected(AdapterView<?> parent) {
66         // TODO Auto-generated method stub
67
68     }
69 }