巧用ViewPager实现驾考宝典做题翻页效果

public class ReaderViewPager extends ViewPager { public ReaderViewPager(Context context) {  this(context, null); } public ReaderViewPager(Context context, AttributeSet attrs) {  super(context, attrs);  setReadEffect();  setScrollerDuration(); } private void setScrollerDuration() {  try {   Field field = ViewPager.class.getDeclaredField("mScroller");   field.setAccessible(true);   FixedSpeedScroller scroller = new FixedSpeedScroller(getContext(),     new DecelerateInterpolator());   field.set(this, scroller);   scroller.setmDuration(300);  } catch (Exception e) {   Log.e("@", "", e);  } } public void setReadEffect() {  setPageTransformer(true, new PageTransformer() {   private static final float MIN_SCALE = 0.75f;   @Override   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 <= 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.setAlpha(1);     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);    }   }  }); }}

<FrameLayout  android:layout_width="match_parent"  android:layout_height="match_parent"><com.example.zhangyipeng.anwerdemo.view.ReaderViewPager   android:id="@+id/readerViewPager"   android:layout_width="match_parent"   android:layout_height="match_parent" />  <!--阴影-->  <ImageView   android:id="@+id/shadowView"   android:layout_width="20dp"   android:layout_height="match_parent"android:background="@mipmap/shadow_right"/> </FrameLayout>

readerViewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {   @Override   public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {    shadowView.setTranslationX(readerViewPager.getWidth()-positionOffsetPixels);   }   @Override   public void onPageSelected(int position) {   }   @Override   public void onPageScrollStateChanged(int state) {   }  });