Android UI控件之Gallery实现拖动式图片浏览效果

<?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" 
  > 
 <Gallery  
 android:id="@+id/gallery1" 
 android:layout_height="fill_parent"  
 android:layout_width="fill_parent" 
 android:spacing="3px"  
 > 
 </Gallery> 
</LinearLayout> 

package com.kiritor.ui_gallery; 
 
import android.app.Activity; 
import android.graphics.Color; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.AdapterView.OnItemClickListener; 
import android.widget.Gallery; 
import android.widget.Toast; 
 
/** 
 * @author 记忆的永恒 
 * 
 */ 
public class MainActivity extends Activity { 
  @Override 
  public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
 
    final Gallery gallery = (Gallery) findViewById(R.id.gallery1); 
    // 将存放图片的ImageAdapter给gallery对象 
    gallery.setAdapter(new ImageAdapter(this)); 
 
    // 设置gallery 的背景图片 
    gallery.setBackgroundResource(R.drawable.first); 
 
    // 设置Gallery的监听事件 
    gallery.setOnItemClickListener(new OnItemClickListener() { 
      @Override 
      public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, 
          long arg3) { 
        switch (arg2) { 
        case 0: 
          gallery.setBackgroundResource(R.drawable.first); 
          break; 
        case 1: 
          gallery.setBackgroundResource(R.drawable.second); 
          break; 
        case 2: 
          gallery.setBackgroundResource(R.drawable.third); 
          break; 
        case 3: 
          gallery.setBackgroundResource(R.drawable.forth); 
          break; 
        case 4: 
          gallery.setBackgroundResource(R.drawable.fifth); 
          break; 
        default: 
          break; 
        } 
      } 
    }); 
  } 
} 

package com.kiritor.ui_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; 
 
public class ImageAdapter extends BaseAdapter{ 
 
//定义Content  
private Context mContext;  
//定义一个数组，存放图片资源  
private Integer[] mImageIds = {  
  R.drawable.first,  
  R.drawable.second,  
  R.drawable.third,  
  R.drawable.forth,  
  R.drawable.fifth,  
   
}; 
 
 //构造  
 public ImageAdapter(Context c){  
  mContext = c;  
 }  
  
 //获取图片的个数  
 public int getCount() {  
  // TODO Auto-generated method stub  
  return mImageIds.length;  
 }  
  
 //获取图片在库中的位置  
 public Object getItem(int position) {  
  // TODO Auto-generated method stub  
  return position;  
 }  
  
 //获取图片在库中的ID  
 public long getItemId(int position) {  
  // TODO Auto-generated method stub  
  return position;  
 } 
 
 //将图片取出来  
 public View getView(int position, View convertView, ViewGroup parent) {  
  //要取出图片，即要定义一个ImageView来存  
  ImageView imageView = new ImageView(mContext);  
  imageView.setImageResource(mImageIds[position]);  
  //设置显示比例类型  
 
  
 
  //设置布局图片以105*150显示 （简单解释――设置数字不一样，图片的显示大小不一样） 
  imageView.setLayoutParams(new Gallery.LayoutParams(240, 200));  
 
 
  imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);  
  return imageView;  
 } 
 
}