Android使用ViewPager实现屏幕滑动效果

import android.support.v4.app.Fragment;
...
public class ScreenSlidePageFragment extends Fragment {

  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup container,
      Bundle savedInstanceState) {
    ViewGroup rootView = (ViewGroup) inflater.inflate(
        R.layout.fragment_screen_slide_page, container, false);

    return rootView;
  }
}

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
...
public class ScreenSlidePagerActivity extends FragmentActivity {
  /**
   * The number of pages (wizard steps) to show in this demo.
   */
  private static final int NUM_PAGES = 5;

  /**
   * The pager widget, which handles animation and allows swiping horizontally to access previous
   * and next wizard steps.
   */
  private ViewPager mPager;

  /**
   * The pager adapter, which provides the pages to the view pager widget.
   */
  private PagerAdapter mPagerAdapter;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_screen_slide);

    // Instantiate a ViewPager and a PagerAdapter.
    mPager = (ViewPager) findViewById(R.id.pager);
    mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
    mPager.setAdapter(mPagerAdapter);
  }

  @Override
  public void onBackPressed() {
    if (mPager.getCurrentItem() == 0) {
      // If the user is currently looking at the first step, allow the system to handle the
      // Back button. This calls finish() on this activity and pops the back stack.
      super.onBackPressed();
    } else {
      // Otherwise, select the previous step.
      mPager.setCurrentItem(mPager.getCurrentItem() - 1);
    }
  }

  /**
   * A simple pager adapter that represents 5 ScreenSlidePageFragment objects, in
   * sequence.
   */
  private class ScreenSlidePagerAdapter extends FragmentStatePagerAdapter {
    public ScreenSlidePagerAdapter(FragmentManager fm) {
      super(fm);
    }

    @Override
    public Fragment getItem(int position) {
      return new ScreenSlidePageFragment();
    }

    @Override
    public int getCount() {
      return NUM_PAGES;
    }
  }
}

ViewPager mPager = (ViewPager) findViewById(R.id.pager);
...
mPager.setPageTransformer(true, new ZoomOutPageTransformer());

public class ZoomOutPageTransformer implements ViewPager.PageTransformer {
  private static final float MIN_SCALE = 0.85f;
  private static final float MIN_ALPHA = 0.5f;

  public void transformPage(View view, float position) {
    int pageWidth = view.getWidth();
    int pageHeight = view.getHeight();

    if (position <-1) { // [-Infinity,-1)
      // This page is way off-screen to the left.
      view.setAlpha(0);

    } else if (position <= 1) { // [-1,1]
      // Modify the default slide transition to shrink the page as well
      float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
      float vertMargin = pageHeight * (1 - scaleFactor) / 2;
      float horzMargin = pageWidth * (1 - scaleFactor) / 2;
      if (position <0) {
        view.setTranslationX(horzMargin - vertMargin / 2);
      } else {
        view.setTranslationX(-horzMargin + vertMargin / 2);
      }

      // Scale the page down (between MIN_SCALE and 1)
      view.setScaleX(scaleFactor);
      view.setScaleY(scaleFactor);

      // Fade the page relative to its size.
      view.setAlpha(MIN_ALPHA +
          (scaleFactor - MIN_SCALE) /
          (1 - MIN_SCALE) * (1 - MIN_ALPHA));

    } else { // (1,+Infinity]
      // This page is way off-screen to the right.
      view.setAlpha(0);
    }
  }
}

public class DepthPageTransformer implements ViewPager.PageTransformer {
  private static final float MIN_SCALE = 0.75f;

  public void transformPage(View view, float position) {
    int pageWidth = view.getWidth();

    if (position <-1) { // [-Infinity,-1)
      // This page is way off-screen to the left.
      view.setAlpha(0);

    } else if (position <= 0) { // [-1,0]
      // Use the default slide transition when moving to the left page
      view.setAlpha(1);
      view.setTranslationX(0);
      view.setScaleX(1);
      view.setScaleY(1);

    } else if (position <= 1) { // (0,1]
      // Fade the page out.
      view.setAlpha(1 - position);

      // Counteract the default slide transition
      view.setTranslationX(pageWidth * -position);

      // Scale the page down (between MIN_SCALE and 1)
      float scaleFactor = MIN_SCALE
          + (1 - MIN_SCALE) * (1 - Math.abs(position));
      view.setScaleX(scaleFactor);
      view.setScaleY(scaleFactor);

    } else { // (1,+Infinity]
      // This page is way off-screen to the right.
      view.setAlpha(0);
    }
  }
}