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Pass data between Activity and Fragment

I want to pass data from Activity to Fragment using Bundle (I used Bundle to passing data between 2 Fragment, and that's worked).
In my Activity I have a ListView, in the OnItemClickListener I want to open a new Fragment, and the Item, which clicked pass through the Activity to this Fragment. But the Item is null, so basically nothing is send to the Fragment.
Here is my Activity:
public class Jegyek extends AppCompatActivity {
View v;
DB mydb;
ListView listView;
private String teszt;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_jegyek);
listView = (ListView)findViewById(R.id.jegyekLista);
mydb = new DB(this);
final ArrayList<String> thelist = new ArrayList<>();
Cursor data = mydb.getTantargynev();
if (data.getCount() == 0) {
Toast.makeText(this, "Nincs jegyek hozzáadva", Toast.LENGTH_SHORT).show();
}
else {
while (data.moveToNext()) {
thelist.add(data.getString(0));
ListAdapter listadapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, thelist);
listView.setAdapter(listadapter);
}
listView.setOnItemClickListener(
new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
teszt = thelist.get(i);
Bundle bundle = new Bundle();
bundle.putString("Tantárgy neve", teszt);
Toast.makeText(Jegyek.this, teszt, Toast.LENGTH_SHORT).show();
Fragment jegyekAllando = new jegyekAllando();
jegyekAllando.setArguments(bundle);
FragmentTransaction FragTan = getSupportFragmentManager().beginTransaction();
FragTan.replace(R.id.jegyekMenu, jegyekAllando);
ListView listaNezet = (ListView) findViewById(R.id.jegyekLista);
listaNezet.setVisibility(View.GONE);
FragTan.commit();
}
}
);
}
}
public String getTanNev () {
System.out.println("WARNING: "+ teszt);
return teszt;
}
}
And my Fragment:
public class jegyekAllando extends Fragment {
DB mydb;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_jegyek_allando, container, false);
Bundle bundle = new Bundle();
String tanNev = bundle.getStrin
g("Tantárgy neve");
Jegyek jegyAct = new Jegyek();
String tanNevv = jegyAct.getTanNev();
mydb = new DB(getActivity());
String jegyAtlag =String.valueOf(mydb.JegyekAtlaga(tanNev));
String jegyDarab =String.valueOf(mydb.JegyekDarabszama(tanNev));
return rootView;
}
}
When I realized, that the bundle is null, I try to pass that List Item through getter, so I changed my Fragment code for that:
Jegyek jegyek = new Jegyek();
String jegy = jegyek.getTanNev();
But that's not solved my problem, so I back to the Bundle, which also have some problem, but I can't find it. Intresting, that in the OnItemClickListener when I Toast the Item it's correct and works, but when I want to display in the console or pass to the Fragment, the value's is null.

From Activity you send data with intent as:
Bundle bundle = new Bundle();
bundle.putString("edttext", "From Activity");
// set Fragmentclass Arguments
Fragmentclass fragobj = new Fragmentclass();
fragobj.setArguments(bundle);
and in Fragment onCreateView method:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
String strtext = getArguments().getString("edttext");
return inflater.inflate(R.layout.fragment, container, false);
}
Hope this helps

Please follow this example:
In your activity, Pass data like
Bundle bundle = new Bundle();
bundle.putString("test", "Test Data");
// set in your testFragment Arguments
TestFragment testFragment = new TestFragment();
testFragment.setArguments(bundle);
And Receive Data from your TestFragment Like
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
String text = getArguments().getString("test");
return inflater.inflate(R.layout.fragment, container, false);
}

In fragment "jegyekAllando" you must get your string from onCreate() with Bundle data = getArguments(), but you create new bundle.

How to send bundle from baseAdapter to a fragment?

Actually i am sending bundle from my base adapter to a new fragment. how I send bundle from adapter to frament.
here is my adapter code:
textViewItemName.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
ExpandableCategoryList fragment = new ExpandableCategoryList();
Bundle bundle = new Bundle();
bundle.putInt("Id",Id);
fragment.setArguments(bundle);
((MainActivity)context).replaceFragment(fragment,
"TAG",null,false);
//Log.e("Hello",fragment.toString());
}
});
and i am receiving mu bundle as
int id = getArguments().getInt("Id",0);
but i am getting that getArguments().getInt() throws null point exception. How I handle it

In your Adapter, write the code
ExpandableCategoryList fragmentProductLaptop = new ExpandableCategoryList();
FragmentTransaction fragmentTransaction=context.getSupportFragmentManager().beginTransaction();
Bundle args = new Bundle();
args.putString("Name",category.getCategoryName());
args.putInt("Id",category.getId());
fragmentProductLaptop.setArguments(bundle);
fragmentTransaction.replace(R.id. homeFrameLayout, fragmentProductLaptop);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
In your Fragment Class, write the below code :
public class ExpandableCategoryList extends Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
String name = getArguments().getString("Name");
String Id = getArguments().getInt("Id",0);
return inflater.inflate(R.layout.fragment, container, false);
}
}

Pass data from Firebase from one fragment to another

I'm trying to pass a CategoryID from Firebase from one fragment to another
using an ImageView Click but my app crashes when an ImageView is clicked.
Here is my code;
MenuFragment.java
FirebaseRecyclerAdapter<Category, MenuViewHolder> adapter;
viewHolder.setItemClickListener(new ItemClickListener() {
#Override
public void onClick(View view, int position, boolean isLongClick) {
CarListFragment cfragment= new CarListFragment ();
Bundle bundle = new Bundle();
bundle.putString("CategoryID",adapter.getRef(position).getKey());
cfragment.setArguments(bundle);
getFragmentManager().beginTransaction()
.replace(R.id.frame_main, cfragment, cfragment.getTag())
.addToBackStack(null)
.commit();
}
});
CarListFragment.java
String CategoryID="";
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v= inflater.inflate(R.layout.fragment_car_list, container, false);
Bundle bundle = this.getArguments();
if (bundle != null) {
CategoryID=getActivity().getIntent().getStringExtra("CategoryID");
}
if(!CategoryID.isEmpty()&& CategoryID!=null){
loadCarList(CategoryID);
}
return v;
}
Logcat

Use bundlebecause it has the data
Bundle bundle = this.getArguments();
if (bundle != null) {
CategoryID = bundle.getString("CategoryID");
// ^^^^^^
}
instead of
CategoryID=getActivity().getIntent().getStringExtra("CategoryID");
because getActivity().getIntent() will give you an Intent object which was previously used to start your activity

use this:
CarListFragment cfragment= new CarListFragment ();
Bundle bundle = new Bundle();
bundle.putString("CategoryID", adapter.getRef(position));
cfragment.setArguments(bundle);
getFragmentManager().beginTransaction()
.replace(R.id.frame_main, cfragment, cfragment.getTag())
.addToBackStack(null)
.commit();
get String:
String str = getArguments().getString("my_string");

android fragment getArguments returns null in oncreateView()

I have two fragments and FilterFragment and LocationListFragment. when I am switching to LocationListFragment.java I am getting values in getArguments() and from LocationListFragment.java to FilterFragment.java getting null values by calling getArgument(); here is the details
In FilterFargment.java code is here for set values:
LocationListFragment locationListFragment = new LocationListFragment();
bundle = new Bundle();
Log.e("",""+locationList.getLocationListFilter().size());
bundle.putParcelable(Constant.LOCATION_LIST_FILTER, locationList);
bundle.putString(Constant.FROM_DATE_FILTER, textView_time_from.getText().toString());
locationListFragment.setArguments(bundle);
((DashbordActivity) getActivity()).switchFragment(locationListFragment, true);
In LocationListFragment.java (getting values)
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Bundle args = getArguments();
if (args != null) {
locationList = args.getParcelable(Constant.LOCATION_LIST_FILTER);
getFromDate = args.getString(Constant.FROM_DATE_FILTER);}}
And here from LocationListFragment on button click send data to FilterFragment sending new values with bundle:
FilterFragment filterFragment =new FilterFragment();//.newInstance(getFromDate, getEndDate, getLocation, getCategories);
Bundle bundle = new Bundle();
bundle.putString(Constant.FROM_DATE_FILTER, getFromDate);
bundle.putString(Constant.WHERE_FILTER, getLocation);
filterFragment.setArguments(bundle);
((DashbordActivity) getActivity()).switchFragment(filterFragment, true);
and in FilterFragment.java while returning back getting null value for getArguments(); code is here:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.fragment_filter, container, false);
Log.e("FilterFragment", "oncreateview");
Bundle args = getArguments();
Log.e("getArguments", "" + getArguments());//getting null here
Also, I have used this method for switching fragment,
public void switchFragment(BaseFragment fragment, boolean keep) {
FragmentManager manager = getSupportFragmentManager();
boolean fragmentPopped = manager.popBackStackImmediate(fragment.getClass().getSimpleName(), 0);
if (!fragmentPopped && manager.findFragmentByTag(fragment.getClass().getSimpleName()) == null) { //fragment not in back stack, create it.
FragmentTransaction tr = manager.beginTransaction();
tr.replace(R.id.container, fragment, fragment.getClass().getSimpleName());
if (keep) {
tr.addToBackStack(fragment.getClass().getSimpleName());
Log.e("keep", "BaseAct:" + keep);
}
tr.commit();
}
}
Can you tell me what I am missing? Any help will be appreciated.

Both If-else statement executing when checking Bundle arguments

In my Android app I'm replacing a Fragment passing an int as argument:
Bundle bundle = new Bundle();
MyFragment fragment = new MyFragment ();
FragmentTransaction ft = getActivity().getSupportFragmentManager().beginTransaction();
bundle.putInt("id", myId);
fragment.setArguments(bundle);
ft.addToBackStack(null).replace(R.id.placeholder, fragment).commit();
Inside MyFragment, I'm checking if this Bundle is null:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_my, container, false);
Bundle args = this.getArguments();
if(args != null) {
Log.d(TAG, "args: "+args);
}
else {
Log.d(TAG, "no args: "+args);
}
return v;
}
My Logcat result:
args: Bundle[{id=1}]
no args: null
Why both if and else are executing?

Why both if and else are executing?
they are probably two different transactions. One that you committed programmatically, the other is probably declared in the layout of hosting activity