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Map fragment is not hidden when switch between fragments Android Studio

I'm trying to switch between fragments using a bottom navigation. However, if I switch to other fragments from the map fragment, the map fragment is still in the background while other fragment is being shown on the front.
Please see my code here:
public class MainActivity extends AppCompatActivity {
private FragmentManager fragmentManager;
private Fragment messageFragment = new MessageFragment();
private Fragment mapFragment = new MapsFragment();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().add(R.id.hostFragment, mapFragment, null).commit();
fragmentManager.beginTransaction().add(R.id.hostFragment, messageFragment, null).commit();
BottomNavigationView bottomNavigationView = findViewById(R.id.bottomNavigationView);
//bottomNavigationView.setSelectedItemId(R.id.mapsFragment);
bottomNavigationView.setOnNavigationItemSelectedListener(navListener);
}
private BottomNavigationView.OnNavigationItemSelectedListener navListener = new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.mapsFragment:
fragmentManager.beginTransaction().hide(messageFragment).show(mapFragment).commit();
break;
case R.id.messageFragment:
fragmentManager.beginTransaction().hide(mapFragment).show(messageFragment).commit();
break;
}
return true;
}
};
}

Your Problem
You are adding both fragments to the same container, R.id.hostFragment.
fragmentManager.beginTransaction().add(R.id.hostFragment, mapFragment, null).commit();
fragmentManager.beginTransaction().add(R.id.hostFragment, messageFragment, null).commit();
Per the documentation for hide and show, this means that you are hiding and then showing the same container.
A Solution
Use two different container views:
fragmentManager.beginTransaction().add(R.id.mapContainer, mapFragment, null).commit();
fragmentManager.beginTransaction().add(R.id.messageContainer, messageFragment, null).commit();
Another Solution
Use replace instead of hiding and showing.
fragmentManager.beginTransaction().add(R.id.hostFragment, mapFragment, null).commit();
// Don't add this in `onCreate`
// fragmentManager.beginTransaction().add(R.id.hostFragment, messageFragment, null).commit();
...
// Replace the fragment currently being displayed
switch (item.getItemId()) {
case R.id.mapsFragment:
fragmentManager.beginTransaction().replace(R.id.hostFragment, mapFragment).commit();
break;
case R.id.messageFragment:
fragmentManager.beginTransaction().replace(R.id.hostFragment, messageFragment).commit();
break;
}

Unable to set text in fragment

I am trying to call a function from my mainActivity to change a TextView in one of my fragments. I have read a couple posts on the best way of doing it but for some reason, none of them seem to work for me. I know the function is working because once a press the button the toast comes up but for some reason the text won't change. I was wondering what the issue could be, or if I am just missing an additional step.
here is the method being called in my mainActivity
public class MainActivity extends AppCompatActivity implements Tab1Fragment.OnCalcClickListener{
private static final String TAG = "MainActivity";
private SectionsPageAdapter mSectionsPageAdpater;
private ViewPager mViewPager;
Tab1Fragment tab1Fragment = new Tab1Fragment();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d(TAG, "onCreate: Starting");
//initializing FragmentManager so the fragments can communicate
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.add(R.id.container, tab1Fragment);
fragmentTransaction.commit();
//declare sections page adapter
mSectionsPageAdpater = new SectionsPageAdapter(getSupportFragmentManager());
//Set up the view pager with the sections adapter
mViewPager = (ViewPager) findViewById(R.id.container);
setUpViewPager(mViewPager);
//create a tab layout object and set it's id to tabs (mainActivity.xml)
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
//
}
// create a sections page view adapter
private void setUpViewPager(ViewPager viewPager){
SectionsPageAdapter adapter = new SectionsPageAdapter(getSupportFragmentManager());
adapter.addFragment(new Tab1Fragment(), "Day");
adapter.addFragment(new Tab2Fragment(), "Info");
adapter.addFragment(new Tab3Fragment(), "Week");
viewPager.setAdapter(adapter);
}
//initialise calculator object
Calculator mainCalculator = new Calculator();
#Override
public void calculateClick(int to_calculate) {
switch (to_calculate){
case 1:
Toast.makeText(getBaseContext(),"working", Toast.LENGTH_SHORT).show();
mainCalculator.freqDay = mainCalculator.freqDay + 1;
mainCalculator.freqWeek = mainCalculator.freqWeek + 1;
mainCalculator.getTotalDay();
tab1Fragment.updateInfo();
break;
}
}
Here is the code for my fragment
public class Tab1Fragment extends Fragment implements
View.OnClickListener{
private static final String TAG = "Tab1Fragment";
//Establishing the buttons & Methods
Button btn1;
Button btn2;
TextView dayView;
OnCalcClickListener onCalcClickListener;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.tab1_fragment, container, false);
//Connecting the buttons to the xml
btn1 = (Button) view.findViewById(R.id.btn_1);
btn1.setOnClickListener(this);
btn2 = (Button) view.findViewById(R.id.btn_2);
btn2.setOnClickListener(this);
dayView = (TextView) view.findViewById(R.id.total_Sales_Day);
return view;
}
//Onclick listener for buttons
public void setOnClickListener(View.OnClickListener listener) {
btn1.setOnClickListener(listener);
btn2.setOnClickListener(listener);
}
//method that will bring data back from activity and set the text
public void updateInfo(){
Toast.makeText(getContext(),"65", Toast.LENGTH_SHORT).show();
dayView.setText("test");
}

To make calls to methods from your fragment in the activity class you need something like this:
public static class MainActivity extends Activity
implements HeadlinesFragment.OnHeadlineSelectedListener{
...
public void onArticleSelected(int position) {
// The user selected the headline of an article from the HeadlinesFragment
// Do something here to display that article
ArticleFragment articleFrag = (ArticleFragment)
getSupportFragmentManager().findFragmentById(R.id.article_fragment);
if (articleFrag != null) {
// If article frag is available, we're in two-pane layout...
// Call a method in the ArticleFragment to update its content
articleFrag.updateArticleView(position);
} else {
// Otherwise, we're in the one-pane layout and must swap frags...
// Create fragment and give it an argument for the selected article
ArticleFragment newFragment = new ArticleFragment();
Bundle args = new Bundle();
args.putInt(ArticleFragment.ARG_POSITION, position);
newFragment.setArguments(args);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack so the user can navigate back
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
}
}
}
Here the activity is calling the updateArticleView method from the fragment, instead of your updateInfo method, but you will get the idea.
Also pay attention to the one-pane scenario, where you need to swap the content and push the arguments using a Bundle object.
See Deliver a Message to a Fragment for more details.

When you add the fragment set a tag to it like this:
MyFragment frag = new MyFragment();
frag.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction().add(R.id.fragment_container, frag, "TAG").commit();
While updating the textview get the instance of fragment using findFragmentByTag()
MyFragment fragment = (MyFragment) getSupportFragmentManager().findFragmentByTag("TAG");
fragment.updateInfo();

How to set a default fragment shown in the main activity?

So i've encountered a small problem today. I was making a bottom navigation view in my app, and after clicking buttons, it replaces the fragment on the screen (and it works perfectly!).
But just after launching the app, and without clicking any button, there is no fragment on the screen.
I've realized that the fragments are shown only after clicking a button, and I'd like to have a default fragment (kalkulatorFragment).
I've been trying my best to somehow set it up, but no success...
public class Main extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
}
private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
= new BottomNavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
kalkulatorFragment kalkulator_fragment = new kalkulatorFragment();
wzoryFragment wzory_fragment = new wzoryFragment();
definicjeFragment definicje_fragment = new definicjeFragment();
switch (item.getItemId()) {
case R.id.kalkulator:
ft.replace(android.R.id.content, kalkulator_fragment);
ft.commit();
return true;
case R.id.wzory:
ft.replace(android.R.id.content, wzory_fragment);
ft.commit();
return true;
case R.id.definicje:
ft.replace(android.R.id.content, definicje_fragment);
ft.commit();
return true;
}
return false;
}

Ok i just figured it out.
I moved the ft.replace to the onCreate() method, so the kalkulatorFragment is going to be shown just after creating an Activity.
public class Main extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
kalkulatorFragment kalkulator_fragment = new kalkulatorFragment();
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.replace(android.R.id.content, kalkulator_fragment);
ft.commit();
BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
}

You need to use this code OUTSIDE of OnCreate Method:
navigation.setSelectedItemId(R.id.IdOFYourItemFromBottomNavigationMenuItems);
I don't know why, but it wont work inside OnCreate method. You can declare and initialize it inside OnCreate method, just can't set the default item in there.
In my case I am using it inside OnCreateOptionsMenu.

How to initiate fragment in fragmentActivity if it is added dynamically?

I have a FragmentActivity in which I am implementing navigation drawer, like if I select any item from drawer list then its fragment is opened in activity. Now my XML layout code to display fragments looks like this
<!-- Framelayout to display Fragments -->
<FrameLayout
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
This means I have not any fragment tags in xml file but I open fragments dynamically from activity as below
private void displayView(int position) {
// update the main content by replacing fragments
Fragment fragment = null;
switch (position) {
case 0:
if(session.isLoggedIn())
{
fragment = new SlidingFragment();
}
else
{
fragment = new LoginFragment();
}
break;
case 1:
fragment = new HomeFragment();
break;
case 2:
fragment = new LoginFragment();
break;
default:
break;
}
if (fragment != null) {
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.frame_container, fragment).commit();}
Now I want to use putFragment to keep fragment state alive for one fragment when orientation changed.so, I coded below on my FragmentActivity's onSaveInstanceState method
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// Log.v(TAG, "In frag's on save instance state ");
FragmentManager manager = getSupportFragmentManager();
fr = new RandomFragment();
manager.putFragment(outState, "randomFragment", fr);
}
here fr is an instance of fragment declared globally Fragment fr and RandomFragment is the fragment that I call in onPostExecute method of homeFragment AsyncTask class. I don't know initiation of RandomFragment is right or not that is fr = new RandomFragment();
Because I don't know how to find fragment by id or tag because there is no fragment tag in my activity layout file. I have just a fragment classes that extends Fragment and i call them like above. I am very confused here. I get the error
02-28 16:28:37.809: E/AndroidRuntime(4336): java.lang.IllegalStateException: Fragment RandomFragment{4247d248} is not currently in the FragmentManager
When I try to change the orientation to landscape. I got this error in putFragment Line. And in onRestoreInstanceState method I write code for getFragment
#Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onRestoreInstanceState(savedInstanceState);
FragmentManager manager = getSupportFragmentManager();
FragmentTransaction t = manager.beginTransaction();
if(savedInstanceState != null)
{
fr = (FragmentRandom)manager.getFragment(savedInstanceState, "randomFragment");
}
else
{
fr = new FragmentRandom();
}
t.add(fr, "randomFragment");
t.commit();
}
But when putFragment on onSaveInstanceState is execute that time I get error and my application stops forcefully so onRestoreInstanceState is not executing.
My actual problem is I don't know I initiate fragment in right way or not. And if it is right then why I get the error? Should I have to do anything with onSaveInstanceState method of fragment also.

You seem to be trying to put a completely new instance of your fragment into the fragment manager. Not only will this cause the issue that you are seeing, if it had worked you wouldn't have been restoring the instance state of that fragment. Try finding the current fragment using the fragment manager.
#Override
protected void onSaveInstanceState(Bundle outState)
{
super.onSaveInstanceState(outState);
FragmentManager manager = getSupportFragmentManager();
Fragment fr = manager.findFragmentById(R.id.frame_container);
manager.putFragment(outState, "randomFragment", fr);
}

Getting Actionbar Tabs to Stick on Fragment

I currently have a MainActivity.java which should be the only activity class. Though in that activity class I have a nav-drawer which links to other fragment views.
Currently the main issue Im facing is implementing tabs under a fragment and making them just be available for only that fragment and subfragments. I ran my application and the tabs appeared, but they also appear on other fragments after I visit the TeamsAndDriversFragment.
In my MainActivity.java I have the following function which helps point to the fragments it will generate once someone clicks on them in the nav-drawer:
/**
* Diplaying fragment view for selected nav drawer list item
* */
private void displayView(int position) {
// update the main content by replacing fragments
Fragment fragment = null;
switch (position) {
case 0:
fragment = new TimeAndScoringFragment();
break;
case 1:
fragment = new ScheduleFragment();
break;
case 2:
fragment = new StandingsFragment();
break;
case 3:
fragment = new TeamsAndDriversFragment();
break;
case 4:
fragment = new NewsFragment();
break;
default:
break;
}
if (fragment != null) {
// Create a fragment transaction object to be able to switch fragments
FragmentTransaction transaction = getFragmentManager().beginTransaction();
// Replace whatever is in the fragment container view with this fragment,
// and add the transaction to the back stack
transaction.replace(R.id.frame_container, fragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
// update selected item and title, then close the drawer
mDrawerList.setItemChecked(position, true);
mDrawerList.setSelection(position);
setTitle(navMenuTitles[position]);
mDrawerLayout.closeDrawer(mDrawerList);
} else {
// error in creating fragment
Log.e("MainActivity", "Error in creating fragment");
}
}
Here is my current TeamsAndDriversFragment class where I have an actionbar navigation with tabs:
public class TeamsAndDriversFragment extends Fragment implements TabListener {
private List<Fragment> fragList = new ArrayList<Fragment>();
#Override
public void onCreate(Bundle savedInstance) {
super.onCreate(savedInstance);
ActionBar bar = getActivity().getActionBar();
bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
Tab mTeamsTab = bar.newTab();
mTeamsTab.setText("Teams");
mTeamsTab.setTabListener(this);
bar.addTab(mTeamsTab);
Tab mDriversTab = bar.newTab();
mDriversTab.setText("Drivers");
mDriversTab.setTabListener(this);
bar.addTab(mDriversTab);
}
#Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
Fragment f = null;
TabFragment tf = null;
if(fragList.size() > tab.getPosition()) {
fragList.get(tab.getPosition());
}
if(f == null) {
tf = new TabFragment();
Bundle data = new Bundle();
data.putInt("idx", tab.getPosition());
tf.setArguments(data);
fragList.add(tf);
} else {
tf = (TabFragment) f;
}
ft.replace(android.R.id.content, tf);
}
#Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
if(fragList.size() > tab.getPosition()) {
ft.remove(fragList.get(tab.getPosition()));
}
}
}

In the displayView() method simply remove all tabs from the ActionBar, this way you'll always have a clean ActionBar with the exception of the TeamsAndDriversFragment fragment:
private void displayView(int position) {
getSupportActionBar().removeAllTabs();
// ...
}