How to use

removeOnPageChangeListener

method

in

androidx.viewpager.widget.ViewPager

  /**
   * @deprecated User ViewPager addOnPageChangeListener
   */
  @Deprecated public void setOnPageChangeListener(
      ViewPager.OnPageChangeListener onPageChangeListener) {
    if (mViewpager == null) {
      throw new NullPointerException("can not find Viewpager , setViewPager first");
    }
    mViewpager.removeOnPageChangeListener(onPageChangeListener);
    mViewpager.addOnPageChangeListener(onPageChangeListener);
  }
}

private void init(Context context) {
  super.removeOnPageChangeListener(onPageChangeListener);
  super.addOnPageChangeListener(onPageChangeListener);
}

public void setViewPager(@Nullable ViewPager viewPager) {
  mViewpager = viewPager;
  if (mViewpager != null && mViewpager.getAdapter() != null) {
    mLastPosition = -1;
    createIndicators();
    mViewpager.removeOnPageChangeListener(mInternalPageChangeListener);
    mViewpager.addOnPageChangeListener(mInternalPageChangeListener);
    mInternalPageChangeListener.onPageSelected(mViewpager.getCurrentItem());
  }
}

@Override
public void setupWithViewPager(ViewPager viewPager) {
  if (viewPager == null) {
    return;
  }
  mViewPager = viewPager;
  if (mPageChangeListener != null) {
    mViewPager.removeOnPageChangeListener(mPageChangeListener);
  } else {
    mPageChangeListener = new ViewPagerPageChangeListener();
  }
  if (mNavigationController != null) {
    int n = mViewPager.getCurrentItem();
    if (mNavigationController.getSelected() != n) {
      mNavigationController.setSelect(n);
    }
    mViewPager.addOnPageChangeListener(mPageChangeListener);
  }
}

@Override
public void setViewPager(ViewPager view) {
  if (mViewPager == view) {
    return;
  }
  if (mViewPager != null) {
    mViewPager.removeOnPageChangeListener(this);
  }
  if (view.getAdapter() == null) {
    throw new IllegalStateException("ViewPager does not have adapter instance.");
  }
  mViewPager = view;
  mViewPager.addOnPageChangeListener(this);
  invalidate();
}

private void onDetachedFromViewPager(@NonNull ViewPager pager) {
  if (mView instanceof TabStripView)
    ((TabStripView) mView).onDetachedFromViewPager(pager);
  else if (mView instanceof TabStripViewGroup)
    ((TabStripViewGroup) mView).onDetachedFromViewPager(pager);
  pager.removeOnPageChangeListener(this);
  pager.removeOnAdapterChangeListener(this);
  final PagerAdapter adapter = pager.getAdapter();
  if (adapter != null) {
    adapter.unregisterDataSetObserver(this);
  }
}

/**
 * Unregister internal listener objects, release object references, etc.
 * This method should be called in order to avoid memory leaks.
 */
public void release() {
  cancelPendingAdjustTabMode();
  cancelPendingSetTabsFromPagerAdapter();
  cancelPendingUpdateScrollPosition();
  if (mInternalOnAdapterChangeListener != null) {
    mViewPager.removeOnAdapterChangeListener(mInternalOnAdapterChangeListener);
    mInternalOnAdapterChangeListener = null;
  }
  if (mInternalDataSetObserver != null) {
    mViewPager.getAdapter().unregisterDataSetObserver(mInternalDataSetObserver);
    mInternalDataSetObserver = null;
  }
  if (mInternalOnTabSelectedListener != null) {
    mTabLayout.removeOnTabSelectedListener(mInternalOnTabSelectedListener);
    mInternalOnTabSelectedListener = null;
  }
  if (mInternalTabLayoutOnPageChangeListener != null) {
    mViewPager.removeOnPageChangeListener(mInternalTabLayoutOnPageChangeListener);
    mInternalTabLayoutOnPageChangeListener = null;
  }
  mViewPager = null;
  mTabLayout = null;
}