Android ViewPager导航小圆点实现无限循环效果

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

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

  <LinearLayout
    android:id="@+id/ll_dots_homepage_top"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_marginBottom="8dp"
    android:gravity="center"
    android:orientation="horizontal">


    <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:clickable="true"
      android:padding="5dp"
      android:visibility="invisible"
      android:src="@drawable/dots"/>

    <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:clickable="true"
      android:padding="5dp"
      android:src="@drawable/dots"/>

    <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:clickable="true"
      android:padding="5dp"
      android:src="@drawable/dots"/>

    <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:clickable="true"
      android:padding="5dp"
      android:src="@drawable/dots"/>

    <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:clickable="true"
      android:padding="5dp"
      android:src="@drawable/dots"/>

    <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:clickable="true"
      android:padding="5dp"
      android:visibility="invisible"
      android:src="@drawable/dots"/>
  </LinearLayout>

</RelativeLayout>

public class HomePageFragment extends BaseFragment {

  private View view;
  private ViewPager mViewPager;//顶部信息推荐栏
  private MyViewPagerAdapter mViewPagerAdapter;
  private LinearLayout ll_dots_homepage_top;//顶部信息推荐栏导航点
  private int GUIDE_NUMBER = 4; //顶部信息推荐栏的数量
  private ImageView[] dotImages; //顶部信息推荐栏引导小圆点
  private int dotCurrentIndex; //顶部信息推荐栏小圆点偏移量
  private MyOnPageChangeListener mOnPageChangeListener;

  private List<View> mListDataViewPage;
  private Context context;

  @Override
  public void onAttach(Context context) {
    super.onAttach(context);
    this.context = context;
  }

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

    initData();
    initView();

    return view;
  }

  /**
   * 初始化一些基础数据
   */
  private void initData() {
    if (mListDataViewPage != null) {
      mListDataViewPage.clear();
      mListDataViewPage = null;
    } else {
      mListDataViewPage = new ArrayList<>();
      // 为了实现无限循环，首位两张图片都是重复的
      int[] resource = new int[]{
          R.drawable.test_viewpager_homepage_4, R.drawable.test_viewpager_homepage_1, R.drawable.test_viewpager_homepage_2, R
          .drawable.test_viewpager_homepage_3, R.drawable.test_viewpager_homepage_4,R.drawable.test_viewpager_homepage_1,};

      for (int i = 0; i < 6; i++) {
        WeakReference<Bitmap> bitmao = new WeakReference<Bitmap>(BitmapFactory
            .decodeResource(getResources(), resource[i]));
        ImageView imageView = new ImageView(context);
        imageView.setImageBitmap(bitmao.get());
        imageView.setScaleType(ImageView.ScaleType.FIT_XY);
        mListDataViewPage.add(imageView);
      }

    }

  }

  /**
   * 初始化底部推信息推荐栏引导小圆点View
   */
  private void initDots() {
    dotImages = new ImageView[mListDataViewPage.size()];
    for (int i = 0; i < mListDataViewPage.size(); i++) {
      dotImages[i] = (ImageView) ll_dots_homepage_top.getChildAt(i);
      dotImages[i].setEnabled(false);
    }
    **//将第一个小圆点设置为高亮，这里的第一个偏移量是1，不是0
    dotImages[1].setEnabled(true);
    dotCurrentIndex = 1;**
  }

  /**
   * initView
   */
  private void initView() {
    findLayout();
    findView();
  }

  /**
   * findLayout
   */
  private void findLayout() {
    ll_dots_homepage_top = (LinearLayout) view.findViewById(R.id.ll_dots_homepage_top);
    initDots();

  }

  /**
   * 初始化控件
   */
  private void findView() {
    mViewPager = (ViewPager) view.findViewById(R.id.vp_homepage)；

    mViewPagerAdapter = new MyViewPagerAdapter(mListDataViewPage);
    mOnPageChangeListener = new MyOnPageChangeListener();
    mViewPager.setAdapter(mViewPagerAdapter);
    mViewPager.setOnPageChangeListener(mOnPageChangeListener);
    **mViewPager.setCurrentItem(1,false); //默认选中第二张图片**
  }

  private class MyOnPageChangeListener implements ViewPager.OnPageChangeListener {

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

    }

    @Override
    public void onPageSelected(int position) {
      if (position < 0 || position > mListDataViewPage.size() || position == dotCurrentIndex) {
        return;
      }

      if ( mListDataViewPage.size() > 1) { //多于1，才会循环跳转
        if ( position < 1) { //首位之前，跳转到末尾（N）
          position = 4;
          mViewPager.setCurrentItem(position,false);
        } else if ( position > 4) { //末位之后，跳转到首位（1）
          position = 1;
          mViewPager.setCurrentItem(position,false); //false:不显示跳转过程的动画

        }else {
          dotImages[dotCurrentIndex].setEnabled(false);
          dotImages[position].setEnabled(true);
          dotCurrentIndex = position;
        }
      }


    }

    @Override
    public void onPageScrollStateChanged(int state) {

    }
  }
}