Viewpager与onpageChangeListener的接口

Question

我尝试过->在viewpager片段中实现的接口，但是默认情况下，第一个片段仅在我滚动页面或轻按水龙头时才获得界面的功能，我想在第一个片段上设置界面的功能。

viewPager.addOnPageChangeListener（new TabLayout.TabLayoutOnPageChangeListener（tabLayout））;

  tabLayout.addOnTabSelectedListener(new TabLayout.BaseOnTabSelectedListener() {
      @Override
      public void onTabSelected(TabLayout.Tab tab) {
          viewPager.setCurrentItem(tab.getPosition());
          final Fragment fragment =adapter.getRegisteredFragment(tab.getPosition());

          //   int position1=(int)fragment.getArguments().get("position");
          // final Fragment fragment1=frag[position1];
          //fragment1.onAttach(Orders_Activity.this);

          fab.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
                  Utils.printValue("reached ","tabselected");
                  //fragmentCommunicatorObj = new OrdersPending();
                  fragmentCommunicatorObj =(fragmentCommunicator) fragment;

                  fragmentCommunicatorObj.passDataToFragment("Hello I am created",getApplicationContext());

              }
          });
      }

      @Override
      public void onTabUnselected(TabLayout.Tab tab) {

      }

      @Override
      public void onTabReselected(TabLayout.Tab tab) {

      }
  });