通过手势实现页面切换，关于Viewpaper介绍。

在android 1.6+的版本中增加了Viewpaper类，通过这个类我们可以很简单的实现左右滑动手指切换页面，Viewpaper需要设置PaperAdapter，在PaperAdapter中实现添加或删除View的功能，具体代码：

public class AwesomePagerActivity extends Activity {    private ViewPager awesomePager;private Context cxt;private AwesomePagerAdapter awesomeAdapter;private LayoutInflater mInflater;private List<View> mListViews;/** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        cxt = this;                awesomeAdapter = new AwesomePagerAdapter();        awesomePager = (ViewPager) findViewById(R.id.awesomepager);        awesomePager.setAdapter(awesomeAdapter);                mListViews = new ArrayList<View>();        mInflater = getLayoutInflater();        mListViews.add(mInflater.inflate(R.layout.layout1, null));        mListViews.add(mInflater.inflate(R.layout.layout2, null));        mListViews.add(mInflater.inflate(R.layout.layout3, null));            }        private class AwesomePagerAdapter extends PagerAdapter{@Overridepublic int getCount() {return mListViews.size();}    /**     * Create the page for the given position.  The adapter is responsible     * for adding the view to the container given here, although it only     * must ensure this is done by the time it returns from     * {@link #finishUpdate()}.     *     * @param container The containing View in which the page will be shown.     * @param position The page position to be instantiated.     * @return Returns an Object representing the new page.  This does not     * need to be a View, but can be some other container of the page.     */@Overridepublic Object instantiateItem(View collection, int position) {((ViewPager) collection).addView(mListViews.get(position),0);return mListViews.get(position);}    /**     * Remove a page for the given position.  The adapter is responsible     * for removing the view from its container, although it only must ensure     * this is done by the time it returns from {@link #finishUpdate()}.     *     * @param container The containing View from which the page will be removed.     * @param position The page position to be removed.     * @param object The same object that was returned by     * {@link #instantiateItem(View, int)}.     */@Overridepublic void destroyItem(View collection, int position, Object view) {((ViewPager) collection).removeView(mListViews.get(position));}@Overridepublic boolean isViewFromObject(View view, Object object) {return view==(object);}    /**     * Called when the a change in the shown pages has been completed.  At this     * point you must ensure that all of the pages have actually been added or     * removed from the container as appropriate.     * @param container The containing View which is displaying this adapter's     * page views.     */@Overridepublic void finishUpdate(View arg0) {}@Overridepublic void restoreState(Parcelable arg0, ClassLoader arg1) {}@Overridepublic Parcelable saveState() {return null;}@Overridepublic void startUpdate(View arg0) {}        }        }

?虽然通过修改源码中launcher类也可以实现类似功能，不过比起重写view这种体力活显然这种方法更环保。