用gallery展示图片，实现中间图片稍大，两边较小的效果

 

实现原理：在onItemSelected事件中，选中galerry中的图片时，把选中的图片放大，把没有选中的缩小。

以下是关键代码

 
   1      
  public  
  void onItemSelected(AdapterView<?> parent, View view,  
  int position, 
  
 
   2              
  long id) { 
  
 
   3          
  // 
   选中Gallery中某个图像时，放大显示该图像 
  
 
   4  
          ImageView imageview = (ImageView)view; 
  
 
   5         ((ImageView) view).setImageDrawable((Drawable) product_image_list.get(position)); 
  
 
   6         view.setLayoutParams( 
  new Gallery.LayoutParams(520 / 2, 318 / 2)); 
  
 
   7         title.setText((String)product_title.get(position)); 
  
 
   8         info.setText((String)product_info.get(position)); 
  
 
   9          
  for( 
  int i=0; i<parent.getChildCount();i++){ 
  
 
  10              
  // 
  缩小选中图片旁边的图片 
  
 
  11  
              ImageView local_imageview = (ImageView)parent.getChildAt(i); 
  
 
  12              
  if(local_imageview!=imageview){ 
  
 
  13                 local_imageview.setLayoutParams( 
  new Gallery.LayoutParams(520/4, 318/4)); 
  
 
  14                 local_imageview.setScaleType(ImageView.ScaleType.FIT_CENTER); 
  
 
  15             } 
  
 
  16         } 
  
 
  17     } 
  
 
  18      
  
 
  19      
  public  
  void onNothingSelected(AdapterView<?> parent) 
  
 
  20     { 
  
 
  21     } 
  
 
  22      
  
 
  23      
  public  
  class ImageAdapter  
  extends BaseAdapter 
  
 
  24     { 
  
 
  25          
  int mGalleryItemBackground; 
  
 
  26          
  private Context mContext; 
  
 
  27  
  
 
  28          
  public ImageAdapter(Context context) 
  
 
  29         { 
  
 
  30             mContext = context; 
  
 
  31  
  // 
              TypedArray typedArray = obtainStyledAttributes(R.styleable.Gallery);
 
  32  
   
  // 
              mGalleryItemBackground = typedArray.getResourceId(
 
  33  
   
  // 
                      R.styleable.Gallery_android_galleryItemBackground, 0);                         
  
 
  34  
          } 
  
 
  35          
  
 
  36          
  public  
  int getCount() 
  
 
  37         { 
  
 
  38              
  return product_image_list.size(); 
  
 
  39         } 
  
 
  40  
  
 
  41          
  public Object getItem( 
  int position) 
  
 
  42         { 
  
 
  43              
  return position; 
  
 
  44         } 
  
 
  45  
  
 
  46          
  public  
  long getItemId( 
  int position) 
  
 
  47         { 
  
 
  48              
  return position; 
  
 
  49         } 
  
 
  50   
  
 
  51          
  public View getView( 
  int position, View convertView, ViewGroup parent) 
  
 
  52         { 
  
 
  53             ImageView imageView =  
  new ImageView(mContext); 
  
 
  54             imageView.setLayoutParams( 
  new Gallery.LayoutParams(520/4, 318/4));//默认都是大图 
  
 
  55             imageView.setImageDrawable((Drawable) product_image_list.get(position)); 
  
 
  56             imageView.setScaleType(ImageView.ScaleType.FIT_CENTER); 
  
 
  57              
  return imageView; 
  
 
  58         } 
  
 
  59     }