Android经过ViewPager实现左右滑动切换图片

import java.io.FileNotFoundException;import java.util.List;import android.content.Context;import android.graphics.Bitmap;import android.net.Uri;import android.support.v4.view.PagerAdapter;import android.support.v4.view.ViewPager;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;public class TestAdapter extends PagerAdapter {	private List<String> mPaths;		private Context mContext;		public TestAdapter(Context cx) {		mContext = cx.getApplicationContext();	}		public void change(List<String> paths) {		mPaths = paths;	}		@Override	public int getCount() {		// TODO Auto-generated method stub		return mPaths.size();	}	@Override	public boolean isViewFromObject(View view, Object obj) {		// TODO Auto-generated method stub		return view == (View) obj;	}	@Override	public Object instantiateItem (ViewGroup container, int position) {		ImageView iv = new ImageView(mContext);		try {			Bitmap bm = BitmapFactory.decodeFile(mPaths.get(position));//载入bitmap			iv.setImageBitmap(bm);		} catch (FileNotFoundException e) {			// TODO Auto-generated catch block			e.printStackTrace();		} catch (OutOfMemoryError e) {			// TODO Auto-generated catch block			e.printStackTrace();		}		((ViewPager)container).addView(iv, 0);		return iv;	}		@Override	public void destroyItem (ViewGroup container, int position, Object object) {		container.removeView((View)object);	}}

    <android.support.v4.view.ViewPager        android:id="@+id/pager"        android:layout_width="fill_parent"        android:layout_height="fill_parent" />

    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        mViewPager = (ViewPager)findViewById(R.id.pager);        mAdapter = new TestAdapter(this);        mViewPager.setAdapter(mAdapter);        mAdapter.change(getList());    }        private List<String> getList() {    	List<String> list = new ArrayList<String>();    	list.add("file:///sdcard/Sunset.jpg");    	list.add("file:///sdcard/Winter.jpg");    	list.add("file:///sdcard/Water lilies.jpg");    	list.add("file:///sdcard/Blue hills.jpg");    	return list;    }