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Android two problems with custom Toolbar

I have implemented my Toolbar. I am attaching the screenshot how it looks like
As you can see there are two problems.
There is an arrow intead of hamburger, whats more this arrow does not turn at all when I swipe drawer from the edge.
Those icons (array, plus and search) are not centered vertically as text (Abc).
Here is my code:
BaseActivity.java
public abstract class BaseActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
public ActionBarDrawerToggle actionBarDrawerToggle;
private DrawerLayout drawerLayout;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
initFields();
}
#Override
public boolean onOptionsItemSelected(#NonNull MenuItem item) {
if (actionBarDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
int id = item.getItemId();
if (id == R.id.nav_login) {
drawerLayout.closeDrawers();
startActivity(new Intent(this, ActivityCredentials.class));
}
return false;
}
public abstract View getView();
private void initFields() {
View view = getView();
NavigationView navigationView = view.findViewById(R.id.navigation_view);
navigationView.setNavigationItemSelectedListener(this);
drawerLayout = view.findViewById(R.id.my_drawer_layout);
actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.find_word, R.string.add);
drawerLayout.addDrawerListener(actionBarDrawerToggle);
actionBarDrawerToggle.syncState();
setSupportActionBar(view.findViewById(R.id.toolbar));
Objects.requireNonNull(getSupportActionBar()).setDisplayHomeAsUpEnabled(true);
}
}
ActivityMain.java
public class ActivityMain extends BaseActivity {
private final FragmentMainHome fragmentMainHome = new FragmentMainHome();
ActivityMainBinding binding;
private BottomNavigationView bottomNavView;
private int startingPosition, newPosition;
#Override
public View getView() {
binding = ActivityMainBinding.inflate(getLayoutInflater());
return binding.getRoot();
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(binding.getRoot());
initBottomNavView();
getSupportFragmentManager().beginTransaction().replace(R.id.content_frame, fragmentMainHome).commit();
}
#Override
public boolean onCreateOptionsMenu(final Menu menu) {
getMenuInflater().inflate(R.menu.menu_action_bar, menu);
final MenuItem searchItem = menu.findItem(R.id.action_search);
SearchView searchView = (SearchView) searchItem.getActionView();
searchView.setQueryHint(getString(R.string.find_word));
searchView.addOnAttachStateChangeListener(new View.OnAttachStateChangeListener() {
#Override
public void onViewAttachedToWindow(View arg0) {
setItemsVisibility(menu, searchItem, false);
}
#Override
public void onViewDetachedFromWindow(View arg0) {
setItemsVisibility(menu, searchItem, true);
}
});
return super.onCreateOptionsMenu(menu);
}
//////////////////////////////////////////////// ORDINARY METHODS ////////////////////////////////////////////////////////////
private void initBottomNavView() {
bottomNavView = binding.bottomNavigation;
bottomNavView.setSelectedItemId(R.id.action_home);
bottomNavView.setItemIconTintList(null);
bottomNavView.setOnItemSelectedListener(item -> {
Toast.makeText(getApplicationContext(), "abc", Toast.LENGTH_SHORT).show();
changeFragmentInActivityMain(item.getItemId());
return true;
});
}
public void changeFragmentInActivityMain(int viewId) {
Fragment fragment = null;
switch (viewId) {
case R.id.action_home:
if (bottomNavView.getSelectedItemId() != R.id.action_home) {
fragment = fragmentMainHome;
newPosition = 0;
}
break;
}
if (fragment != null) {
if (startingPosition > newPosition) {
getSupportFragmentManager()
.beginTransaction()
.setCustomAnimations(R.anim.slide_in_left, R.anim.slide_out_right)
.replace(R.id.content_frame, fragment).commit();
}
if (startingPosition < newPosition) {
getSupportFragmentManager()
.beginTransaction()
.setCustomAnimations(R.anim.slide_in_right, R.anim.slide_out_left)
.replace(R.id.content_frame, fragment).commit();
}
startingPosition = newPosition;
}
}
private void setItemsVisibility(Menu menu, MenuItem exception, boolean visible) {
for (int i = 0; i < menu.size(); ++i) {
MenuItem item = menu.getItem(i);
if (item != exception) item.setVisible(visible);
}
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_height="match_parent"
android:layout_width="match_parent">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?actionBarSize"
android:minHeight="?actionBarSize"
android:background="?colorToolbarBg"
android:gravity="center_vertical"
android:orientation="vertical"
android:padding="8dp" />
<androidx.drawerlayout.widget.DrawerLayout
android:id="#+id/my_drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="#+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toTopOf="#+id/bottom_navigation"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="?attr/colorBottomNavigationViewBg"
app:itemHorizontalTranslationEnabled="true"
app:itemTextColor="?attr/colorBottomNavigationViewItem"
app:layout_constraintBottom_toBottomOf="parent"
app:menu="#menu/menu_bottom_navigation" />
</RelativeLayout>
<com.google.android.material.navigation.NavigationView
android:id="#+id/navigation_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
app:itemIconTint="?colorDayNight"
app:menu="#menu/menu_navigation_drawer" />
</androidx.drawerlayout.widget.DrawerLayout>
</LinearLayout>
EDIT First problem solved, now the second remaining...
EDIT 2 Fully solved :)

navigation drawer not showing properly

I am developing news app and I have implemented navigation drawer
using following link but when I run the code app showing empty white
screen.
below my MainActivity.java class
public class MainActivity extends AppCompatActivity {
private DrawerLayout mDrawer;
private Toolbar toolbar;
private ActionBarDrawerToggle drawerToggle;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Set a Toolbar to replace the ActionBar.
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Find our drawer view
mDrawer = (DrawerLayout) findViewById(R.id.drawer_layout);
NavigationView nvDrawer = (NavigationView) findViewById(R.id.nvView);
// Inflate the header view at runtime
View headerLayout = nvDrawer.inflateHeaderView(R.layout.nav_header);
// We can now look up items within the header if needed
#SuppressLint("ResourceType") ImageView ivHeaderPhoto = headerLayout.findViewById(R.drawable.ic_sportnews);
setupDrawerContent(nvDrawer);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// The action bar home/up action should open or close the drawer.
switch (item.getItemId()) {
case android.R.id.home:
mDrawer.openDrawer(GravityCompat.START);
return true;
}
return super.onOptionsItemSelected(item);
}
private void setupDrawerContent(NavigationView navigationView) {
navigationView.setNavigationItemSelectedListener(
menuItem -> {
selectDrawerItem(menuItem);
return true;
});
}
public void selectDrawerItem(MenuItem menuItem) {
// Create a new fragment and specify the fragment to show based on nav item clicked
Fragment fragment = null;
Class fragmentClass = null;
switch (menuItem.getItemId()) {
case R.id.bbcsports_fragment:
fragmentClass = BBCSportFragment.class;
break;
case R.id.talksports_fragment:
fragmentClass = TalkSportsFragment.class;
break; case R.id.foxsports_fragment:
fragmentClass = FoxSportsFragment.class;
break;
default:
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
// Highlight the selected item has been done by NavigationView
menuItem.setChecked(true);
// Set action bar title
setTitle(menuItem.getTitle());
// Close the navigation drawer
mDrawer.closeDrawers();
}
}
below my activity_main.xml
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- This LinearLayout represents the contents of the screen -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<!-- The ActionBar displayed at the top -->
<include
layout="#layout/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<!-- The main content view where fragments are loaded -->
<FrameLayout
android:id="#+id/flContent"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</LinearLayout>
<!-- The navigation drawer that comes from the left -->
<!-- Note that `android:layout_gravity` needs to be set to 'start' -->
<android.support.design.widget.NavigationView
android:id="#+id/nvView"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#android:color/white"
app:headerLayout="#layout/nav_header"
app:menu="#menu/navigation_menu" />
</android.support.v4.widget.DrawerLayout>
below my Fragment class
public class BBCSportFragment extends Fragment {
public List<Article> articleList = new ArrayList<Article>();
#BindView(R.id.recycler_view)
RecyclerView recyclerView;
private SportNews sportNews;
private ArticleAdapter articleAdapter;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_bbcsport, container, false);
ButterKnife.bind(this, view);
SportInterface sportInterface = SportClient.getApiService();
Call<SportNews> call = sportInterface.getArticles();
call.enqueue(new Callback<SportNews>() {
#Override
public void onResponse(Call<SportNews> call, Response<SportNews> response) {
sportNews = response.body();
if (sportNews != null && sportNews.getArticles() != null) {
articleList.addAll(sportNews.getArticles());
}
articleAdapter = new ArticleAdapter(articleList, sportNews);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext());
recyclerView.setLayoutManager(layoutManager);
recyclerView.setAdapter(articleAdapter);
}
#Override
public void onFailure(Call<SportNews> call, Throwable t) {
}
});
return view;
}
}

How can I implement the bottom navigation bar into an app for android?

Here is a piece of Java code.
The Android app stops when I tap on an item in the BottomNavigationView, it should open a fragment.
public class MainActivity extends AppCompatActivity {
private BottomNavigationView bottomNavigationView;
private BottomNavigationView bottomNavigationView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottomNavigationView);
bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
Unlike if-then and if-then-else statements, the switch statement can have a number of possible execution paths:
switch (item.getItemId()) {
case R.id.item0:
transaction.replace(R.id.content, new Item0_Fragment()).commit();
return true;
case R.id.item1:
transaction.replace(R.id.content, new Item1_Fragment()).commit();
return true;
case R.id.item2:
transaction.replace(R.id.content, new Item2_Fragment()).commit();
return true;
case R.id.item3:
transaction.replace(R.id.content, new Item3_Fragment()).commit();
return true;
}
return false;
}
});
}

First, you did declares two times the BottomNavigationView. In second, you not writed the complete code, leaving aside parts that may be important. However I did write a code for this. Try read my code or just copy and paste. You just need create your fragments, if needs help to do this let me know.
MainActivity.java
public class MainActivity extends AppCompatActivity {
List<Fragment> fragmentList;
MyAdapter myAdapter;
ViewPager viewPager;
BottomNavigationView bottomNavigationView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.i(TAG,"onCreate()");
fragmentList = new ArrayList<>();
fragmentList.add(new Fragment1());
fragmentList.add(new Fragment2());
bottomNavigationView = findViewById(R.id.bottomNavigationView);
viewPager = findViewById(R.id.viewPagerAppActivity);
myAdapter = new MyAdapter(getSupportFragmentManager());
viewPager.setAdapter(myAdapter);
viewPager.setCurrentItem(0);
bottomNavigationView.setOnNavigationItemSelectedListener(botNavViewItemSelectedListener());
}
public BottomNavigationView.OnNavigationItemSelectedListener botNavViewItemSelectedListener() {
return new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.itemFragment1:
viewPager.setCurrentItem(0);
break;
case R.id.itemFragment2:
viewPager.setCurrentItem(1);
break;
}
return true;
}
};
}
public class MyAdapter extends FragmentStatePagerAdapter {
public MyAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
return fragmentList.get(position);
}
#Override
public int getCount() {
return fragmentList.size();
}
}
}
activity_main.xml
<android.support.constraint.ConstraintLayout android:layout_width="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_height="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<android.support.v4.view.ViewPager
android:id="#+id/viewPagerAppActivity"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="#id/bottomNavigationView"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginBottom="0dp"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginTop="0dp"
app:layout_constraintVertical_bias="1.0" />
<android.support.design.widget.BottomNavigationView
app:menu="#menu/menu_bottom"
android:id="#+id/bottomNavigationView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:itemBackground="#color/colorPrimary"
app:itemIconTint="#drawable/bottom_bar_item_selector"
app:itemTextColor="#drawable/bottom_bar_item_selector"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent" />
</android.support.constraint.ConstraintLayout>
menu_bottom.xml to populate my menu of navigation
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item android:id="#+id/itemFragment1" android:title="Frag1" android:enabled="true" app:showAsAction="always|withText" android:icon="#mipmap/ic_launcher"/>
<item android:id="#+id/itemFragment2" android:title="Frag2" android:enabled="true" app:showAsAction="always|withText" android:icon="#mipmap/ic_launcher"/>
</menu>

*For fragment click this http://www.truiton.com/2017/01/android-bottom-navigation-bar-example/
*For activities
Following code makes the bottom navigation for activites(same feel as to fragment)
STEP 1: Create a BaseActivity and name it as BaseActivity
BaseActivity.java
public abstract class BaseActivity extends AppCompatActivity implements
BottomNavigationView.OnNavigationItemSelectedListener{
protected BottomNavigationView navigationView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(getContentViewId());
navigationView = findViewById(R.id.navigation);
navigationView.setOnNavigationItemSelectedListener(this);
BottomNavigationViewHelper.disableShiftMode(navigationView);
}
#Override
protected void onStart() {
super.onStart();
updateNavigationBarState();
}
#Override
public void onPause() {
super.onPause();
}
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
int itemId = item.getItemId();
if (itemId == R.id.menuBuilding) {
startActivity(new Intent(this, ActivityA.class));
} else if (itemId == R.id.menuChat) {
startActivity(new Intent(this, ActivityB.class));
} else if (itemId == R.id.menuProfile) {
startActivity(new Intent(this, ActivityC.class));
}
overridePendingTransition(0, 0);
finish();
return true;
}
private void updateNavigationBarState() {
int actionId = getNavigationMenuItemId();
selectBottomNavigationBarItem(actionId);
}
void selectBottomNavigationBarItem(int itemId) {
Menu menu = navigationView.getMenu();
for (int i = 0, size = menu.size(); i < size; i++) {
MenuItem item = menu.getItem(i);
boolean shouldBeChecked = item.getItemId() == itemId;
if (shouldBeChecked) {
item.setChecked(true);
break;
}
}
}
abstract int getContentViewId();
abstract int getNavigationMenuItemId();
}
STEP 2:
Create a child activity and name it as ActivityA and copy paste the following code
ActivityA.java
public class ActivityA extends BaseActivity implements {
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
int getContentViewId() {
return R.layout.activity_a_layout;
}
#Override
int getNavigationMenuItemId() {
return R.id.menuBuilding;
}
}
Similary create ActivityB.java and ActivityC.java .Make both classes similar to ActivityA.java.But the different is ActivityA.java returns
#Override
int getNavigationMenuItemId() {
return R.id.menuBuilding;
}
and
ActivityB.java returns
#Override
int getNavigationMenuItemId() {
return R.id.menuChat;
}
and
ActivityC.java returns`
#Override
int getNavigationMenuItemId() {
return R.id.menuProfile;
}
Also create layout for two java class and copy paste the activity_a_layout.xml code to both layouts of ActivityB.java and ActivityC.java
STEP 3 : Create a layout named activity_a_layout and copy paste the following code
'activity_a_layout.xml'
<?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"
xmlns:app="http://schemas.android.com/apk/res-auto"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/toolbar"
android:background="#android:color/white">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Coming soon..."
android:textSize="19sp"
android:textStyle="bold"
android:layout_centerInParent="true"/>
</RelativeLayout>
<include
android:id="#+id/navigation"
layout="#layout/bottom_navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true" />
</RelativeLayout>
STEP 4:
Create a layout named bottom_navigation and copy pase the following code
bottom_navigation.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.BottomNavigationView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/dark_grey"
app:itemIconTint="#drawable/nav_item_menu_selector"
app:itemTextColor="#drawable/nav_item_menu_selector"
app:menu="#menu/bottom_nav_items" />
STEP 5: Create a menu folder inside res and create a file named bottom_nav_items inside menu and copy paste the below code
bottom_nav_items.xml
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/menuChat"
android:icon="#drawable/ic_chat"
android:title="Chat" />
<item
android:id="#+id/menuBuilding"
android:icon="#drawable/ic_building_white"
android:title="Company" />
<item
android:id="#+id/menuProfile"
android:icon="#drawable/menu_item_profile"
android:title="Profile"
app:itemTextColor="#android:color/transparent" />
</menu>
**Dont forgot to declare ActivityA.java,ActivityB.java and ActivityC.java in manifest
HAPPY CODING

Textview in a fragment of Viewpager doesn't update right

I have created A layout and I dynamically add tabs according to data I receive. I do the same with fragments updating the Text View dynamically. Although when the layout loads and if I swipe through the fragments or view pager (sorry I am new to all these hope my terminology is right) they update just okay (meaning there is sometimes lag in updating not much of an issue) and with right data. although, if in fresh I open the layout and click on tab to change my fragments I get no data or wrong data. Example:- when Layout loads for first time my first & third tab load up fine. If I click on a second Tab (not swiping but touching the tabs on top for the whole time), my second tab doesn't have any data in its fragment. On moving round here and there selecting tabs randomly first tab loads second tabs data, but second tab never loads anything. Its not the same when I swipe if I load page new or for first time.
Let me know where I am doing wrong. Thank you.
Here is my code:-
Layout file - show_score.xml
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.lp.activity.ShowScorePassagesActivity">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/children_school"
android:scaleType="centerCrop"
android:alpha="0.5"
android:layout_below="#+id/appBackBar"/>
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="#dimen/appbar_padding_top"
android:theme="#style/AppTheme.AppBarOverlay">
<include android:id="#+id/appBackBar"
layout="#layout/detail_appbar"/>
<android.support.design.widget.TabLayout
android:id="#+id/passagetabs"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</android.support.design.widget.TabLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
Fragment File - fragment_show_score_passage.xml
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/constraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.lp.activity.ShowScorePassagesActivity$PlaceholderFragment">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- TODO: Update blank fragment layout -->
<android.support.v7.widget.CardView
android:id="#+id/cardView4"
android:layout_width="match_parent"
android:layout_height="200dp"
app:cardElevation="5dp"
android:scaleType="fitXY"
android:layout_margin="5dp">
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
style="#style/scrollbar_shape_style">
<TextView
android:id="#+id/showScore"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="18dp"
android:scaleType="fitXY"
android:text="TextView"
android:autoLink="web"
android:linksClickable="true"
android:padding="20dp"
android:clipToPadding="false"/>
</ScrollView>
</android.support.v7.widget.CardView>
<android.support.v7.widget.CardView
android:id="#+id/cardView5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardElevation="5dp"
android:layout_below="#+id/cardView4"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:layout_marginTop="5dp">
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
style="#style/scrollbar_shape_style">
<GridView
android:id="#+id/fluencyAudioGrid"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:numColumns="auto_fit"
android:horizontalSpacing="2dp"
android:verticalSpacing="5dp"
android:columnWidth="120dp"
android:paddingTop="10dp"
android:paddingBottom="10dp"
android:clipToPadding="false"
android:stretchMode="spacingWidthUniform"
layout="#layout/icons_for_dashboard"
android:scrollbarThumbVertical="#drawable/scroolbar_style"
android:scrollbarTrackVertical="#drawable/scroolbar_style_background">
</GridView>
</ScrollView>
</android.support.v7.widget.CardView>
</RelativeLayout>
</android.support.constraint.ConstraintLayout>
And the main Java File where the magic happens - ShowScorePassageActivity.java
public class ShowScorePassagesActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
public GridView gridView;
public ArrayList<String> gridItems = new ArrayList<String>();
public static TextView fragTextView;
static String fragNewTextView = "";
public static ArrayList<String> fluencyMarksList = new ArrayList<>();
public TabLayout tabLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.show_score_passages);
Intent in = getIntent();
String intentData = in.getStringExtra("intentData");
String fluencyMarks = in.getStringExtra("fluencyMarks");
tabLayout = (TabLayout) findViewById(R.id.passagetabs);
String mFluencyMarkList []= fluencyMarks.split("#");
fluencyMarksList = new ArrayList<String>(Arrays.asList(mFluencyMarkList));
int count = 1;
int counts=fluencyMarksList.size();
for(int i = 0; i < counts; i++){
tabLayout.addTab(tabLayout.newTab().setText("Passage "+count));
count=count+1;
}
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
mViewPager = (ViewPager) findViewById(R.id.container);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager(), tabLayout.getTabCount());
mViewPager.setAdapter(mSectionsPagerAdapter);
mViewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
#Override
public void onTabSelected(TabLayout.Tab tab) {
mViewPager.setCurrentItem(tab.getPosition());
int position = tab.getPosition();
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
if (position ==0){
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(0), Html.FROM_HTML_MODE_COMPACT));
}
else if (position ==1){
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(1) , Html.FROM_HTML_MODE_COMPACT));
}
else if (position ==2){
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(2) , Html.FROM_HTML_MODE_COMPACT));
}
} else {
if (position ==0){
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(0)));
}
else if (position ==1){
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(1)));
}
else if (position ==2){
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(2)));
}
}
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
fragTextView.setText("");
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_show_score_passages, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
public PlaceholderFragment() {
}
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
#RequiresApi(api = Build.VERSION_CODES.N)
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_show_score_passages, container, false);
fragTextView = (TextView) rootView.findViewById(R.id.showScore);
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(0) , Html.FROM_HTML_MODE_COMPACT));
} else {
fragTextView.setText(Html.fromHtml(fluencyMarksList.get(0)));
}
return rootView;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
}
public class SectionsPagerAdapter extends FragmentPagerAdapter {
int mNumOfTabs;
Fragment fragment = null;
public SectionsPagerAdapter(FragmentManager fm, int NumOfTabs) {
super(fm);
this.mNumOfTabs=NumOfTabs;
}
#Override
public Fragment getItem(int position) {
return PlaceholderFragment.newInstance(position + 1);
}
#Override
public int getCount() {
return mNumOfTabs;
}
}
}

This is what I did:
It is only a example of what worked for me in the hopes of helping you
In OnCreate:
ViewPager mViewPager = (ViewPager) findViewById(R.id.container);
this.addPages(mViewPager);
mViewPager.setOffscreenPageLimit(3);
TabLayout tabLayout = (TabLayout) findViewById(R.id.mTab_ID);
tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
tabLayout.setupWithViewPager(mViewPager);
tabLayout.addOnTabSelectedListener(listener(mViewPager));
Then add the fragments to the TabLayout by doing:
//ADD ALL PAGES TO TABLAYOUT
private void addPages(ViewPager pager) {
adapter = new MyFragPagerAdapter(getSupportFragmentManager());
adapter.addPage(new FragmentAdapter1());
adapter.addPage(new FragmentAdapter2());
adapter.addPage(new FragmentAdapter3());
//SET ADAPTER TO PAGER
pager.setAdapter(adapter);
}
Then implement TabLayout click events OnTabSelectedListener by doing:
//TabLayout Click Events
private TabLayout.OnTabSelectedListener listener(final ViewPager pager) {
return new TabLayout.OnTabSelectedListener() {
#Override
public void onTabSelected(TabLayout.Tab tab) {
pager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
}
};
}

PreferenceFragmentCompat doesn't show

I need help to fix a problem with PreferenceFragmentCompat, which simply doesn't shows, no error in console, no message, nothing, just a blank page.
The fragment is shown as a result of the selection of an element in a navigation drawer. Here's the Activity XML:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="false">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="#+id/list_container"
android:layout_width="match_parent"
android:layout_height="match_parent">
</FrameLayout>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_marginBottom="24dp"
android:layout_marginEnd="24dp"
app:elevation="12dp"
app:fabSize="normal"
app:rippleColor="#color/nowControlsNormal"
app:srcCompat="#android:drawable/ic_popup_sync" />
</FrameLayout>
<android.support.design.widget.NavigationView
android:id="#+id/drawer"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
app:headerLayout="#layout/drawer_top"
app:itemIconTint="#color/nowBlack"
app:itemTextColor="#color/nowBlack"
app:menu="#menu/drawer_menu" />
</android.support.v4.widget.DrawerLayout>
Here's the activity Java:
public class HomeActivity extends AppCompatActivity {
SharedPreferences settings;
private DrawerLayout drawerLayout;
private ActionBarDrawerToggle drawerToggle;
NavigationView nav;
TextView drawerUsername;
FloatingActionButton fab;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
settings = getSharedPreferences("NowCLOUD", 0);
setContentView(R.layout.activity_home);
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
nav = (NavigationView) findViewById(R.id.drawer);
fab = (FloatingActionButton) findViewById(R.id.fab);
View headerView = nav.getHeaderView(0);
drawerUsername = (TextView) headerView.findViewById(R.id.drawer_username);
fab.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
//TODO: Gestire aggiornamento al click della FAB
}
});
getSupportActionBar().setTitle("Home");
drawerToggle = new ActionBarDrawerToggle(this, drawerLayout, R.string.drawer_open, R.string.drawer_close) {
public void onDrawerClosed(View view) {
super.onDrawerClosed(view);
}
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
}
};
drawerLayout.setDrawerListener(drawerToggle);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
getSupportFragmentManager().beginTransaction()
.add(R.id.list_container, HomeFragment.newInstance())
.commit();
drawerUsername.setText(settings.getString("username", "Error"));
nav.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
menuItem.setChecked(true);
drawerLayout.closeDrawers();
displayView(menuItem.getItemId());
return true;
}
});
}
public void displayView(int viewId) {
Fragment fragment = null;
String title = getString(R.string.app_name);
switch (viewId) {
case R.id.drawer_home:
fragment = HomeFragment.newInstance();
title = "Home";
break;
case R.id.drawer_settings:
fragment = SettingsFragment.newInstance();
title = "Settings";
break;
}
if (fragment != null) {
getSupportFragmentManager().beginTransaction()
.replace(R.id.list_container, fragment)
.commit();
}
// set the toolbar title
if (getSupportActionBar() != null) {
getSupportActionBar().setTitle(title);
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
}
}
Here's the Fragment's XML:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.preference.PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="match_parent">
<android.support.v7.preference.PreferenceCategory
android:title="#string/settings_synchronization">
<android.support.v7.preference.SwitchPreferenceCompat
android:key="auto_updates"
android:title="#string/settings_auto_sync" />
</android.support.v7.preference.PreferenceCategory>
</android.support.v7.preference.PreferenceScreen>
Here's the Fragment's Java:
public class SettingsFragment extends PreferenceFragmentCompat {
View rootView;
#Override
public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
addPreferencesFromResource(R.xml.fragment_settings);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
//rootView = inflater.inflate(R.xml.fragment_settings,container,false);
return rootView;
}
#Override
public PreferenceFragmentCompat getCallbackFragment() {
return this;
}
public static SettingsFragment newInstance() {
Bundle args = new Bundle();
SettingsFragment fragment = new SettingsFragment();
fragment.setArguments(args);
return fragment;
}
}
I've removed all of the code which was useless for this purpose. Sorry for the huge amount of code.

I've figured it out by myself:
when you are using preferencefragment you cannot override the onCreateView method, or you'll get a blank screen.