title: ViewPager addOnPageChangeListener not working on same tabClick
body: <p>I have a <code>ViewPager</code> with <code>addOnPageChangeListener</code>. <code>ViewPager</code> has 3 tabviews (tab1, tab2, tab3). When a user clicks tab2, it loads some data (Basically it a <code>RecyclerView</code>). At this moment, if user again clicks tab2, I need to reload the data but in this case <code>addOnPageChangeListener</code> is not triggered.</p>
  
  <p>My Code: </p>
  
  <pre><code>customPagerAdapter = new CustomPagerAdapter(getSupportFragmentManager(), MainActivity.this);
  viewPager.setAdapter(customPagerAdapter);
  
  viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
      public void onPageScrollStateChanged(int state) {
      }
  
      public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
      }
  
      public void onPageSelected(int position) {
          Log.i("TAG", "position: " + position);
          switch (position) {
              case 0:
                  addingMarker(LocationData.find(LocationData.class, "Category = ? ", "1"));
                  break;
              case 1:
                  addingMarker(LocationData.find(LocationData.class, "Category = ? ", "2"));
                  break;
              case 2:
                  addingMarker(LocationData.find(LocationData.class, "Category = ? ", "3"));
                  break;
          }
      }
  });
  viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
  tabLayout.setupWithViewPager(viewPager);
  </code></pre>