android中Gallery与ImageSwicther解析

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3    android:layout_height="fill_parent"
 4    android:layout_width="fill_parent">
 5     <ImageSwitcher 
 6         android:id="@+id/imageswitcher"
 7         android:layout_width="fill_parent"
 8         android:layout_height="fill_parent">
 9     </ImageSwitcher>
10     <Gallery 
11         android:id="@+id/gallery"
12         android:layout_width="fill_parent"
13         android:layout_height="wrap_content"
14         android:layout_alignParentBottom="true"/>
15 </RelativeLayout>

 1 public class MainActivity extends Activity implements ViewFactory,OnItemSelectedListener{
 2 
 3 private Gallery gallery;
 4 private ImageSwitcher is;
 5 private int galleryItemBackGroundId;
 6 private int imageId[]={R.drawable.gril1,R.drawable.gril2,R.drawable.gril3,R.drawable.gril4,R.drawable.gril5,
 7           R.drawable.gril6,R.drawable.gril7,R.drawable.gril8,R.drawable.gril9,R.drawable.gril10,
 8           R.drawable.gril11};
 9     @Override
10     protected void onCreate(Bundle savedInstanceState) {
11         super.onCreate(savedInstanceState);
12         requestWindowFeature(Window.FEATURE_NO_TITLE);  //去除标题
13         setContentView(R.layout.main);
14         
15         gallery = (Gallery) findViewById(R.id.gallery);
16         gallery.setAdapter(new MyGalleryAdapter(MainActivity.this));
17         gallery.setOnItemSelectedListener(this);  //设置选项监听用setOnItemSelectedListener
18         
19         is = (ImageSwitcher) findViewById(R.id.imageswitcher);
20         is.setFactory(this);
21    22         is.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in));
23         is.setOutAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_out));
24         
25     }
26 
27     @Override
28     public boolean onCreateOptionsMenu(Menu menu) {
29         // Inflate the menu; this adds items to the action bar if it is present.
30         getMenuInflater().inflate(R.menu.main, menu);
31         return true;
32     }
33 
34     class MyGalleryAdapter extends BaseAdapter{
35 
36         private Context context;
37     
38         public MyGalleryAdapter(Context context) {
39             this.context = context;
40             TypedArray typed = obtainStyledAttributes(R.styleable.Gallery);   //获得属性集合
41             galleryItemBackGroundId = typed.getResourceId(R.styleable.Gallery_android_galleryItemBackground, 0);
42         }
43 
44         @Override
45         public int getCount() {
46             // TODO 自动生成的方法存根
47             return Integer.MAX_VALUE;  //为了实现画廊中图片循环效果，才设置return_Integer.Max_VALUE,其实可以return imageId.length;
48         }
49 
50         @Override
51         public Object getItem(int position) {
52             // TODO 自动生成的方法存根
53             return imageId[position];
54         }
55 
56         @Override
57         public long getItemId(int position) {
58             // TODO 自动生成的方法存根
59             return position;
60         }
61 
62         @Override
63         public View getView(int position, View convertView, ViewGroup parent) {
64             // TODO 自动生成的方法存根
65             ImageView imageView = new ImageView(context); 
66             imageView.setImageResource(imageId[position%imageId.length]);  设置图片到view中
67             imageView.setScaleType(ScaleType.FIT_XY);
68             imageView.setLayoutParams(new Gallery.LayoutParams(156, 100)); 
69             imageView.setBackgroundResource(galleryItemBackGroundId);  //设置imageview 背景
70             return imageView;
71         }
72         
73     }
74 
75     @Override
76     public View makeView() {
77         ImageView imageView  = new ImageView(MainActivity.this);
78         imageView.setAdjustViewBounds(true);   //是否保持宽高比。需要与maxWidth、MaxHeight一起使用，否则单独使用没有效果

79         imageView.setScaleType(ScaleType.FIT_XY);
80         imageView.setLayoutParams(new ImageSwitcher.LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.FILL_PARENT));
81         
82         return imageView;
83     }
84 
85     @Override
86     public void onItemSelected(AdapterView<?> parent, View view, int position,      //画廊(Gallery)选中的项
87             long id) {
88         // TODO 自动生成的方法存根
89         
90         is.setImageDrawable(getResources().getDrawable(imageId[position%imageId.length]));
91     }
92 
93     @Override
94     public void onNothingSelected(AdapterView<?> parent) {
95         // TODO 自动生成的方法存根
96         
97     }
98 }