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;   }  }