Merge pull request #4 from TonyTangAndroid/persist_the_view_pager_state

Persist the fragment state

Author: TonyTangAndroid

app/src/main/java/io/anycopy/googleplusdemo/DashboardFragment.java

@@ -29,7 +29,9 @@ public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup c
     public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
         ViewPager viewPager = view.findViewById(R.id.view_pager);
-        viewPager.setAdapter(new GooglePlusFragmentPageAdapter(getChildFragmentManager()));
+        GooglePlusFragmentPageAdapter adapter = new GooglePlusFragmentPageAdapter(getChildFragmentManager());
+        viewPager.setAdapter(adapter);
+        viewPager.setOffscreenPageLimit(adapter.getCount() - 1);
         TabLayout tabLayout = view.findViewById(R.id.tabs);
         tabLayout.setupWithViewPager(viewPager);
     }

app/src/main/java/io/anycopy/googleplusdemo/MainActivity.java

@@ -39,7 +39,9 @@ protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         viewPager = findViewById(R.id.view_pager);
-        viewPager.setAdapter(new GooglePlusFragmentPageAdapter(getSupportFragmentManager()));
+        GooglePlusFragmentPageAdapter adapter = new GooglePlusFragmentPageAdapter(getSupportFragmentManager());
+        viewPager.setAdapter(adapter);
+        viewPager.setOffscreenPageLimit(adapter.getCount() - 1);
         BottomNavigationView navigation = findViewById(R.id.navigation);
         navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
     }