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How can i pass adapter to fragment like in intent

I am new to android and I am trying to call my MapFragment from adapter after on click using intent below is my code
Below is adapter code:
public View getView(int position, #Nullable View convertView, #NonNull ViewGroup parent) {
final BusInfo info = getItem(position);
View view = LayoutInflater.from(context).inflate(R.layout.bus_only_list,null);
TextView busname;
busname = (TextView) view.findViewById(R.id.busname);
busname.setText(info.name);
view.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
pref = context.getSharedPreferences("busInfo",Context.MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putString("bus_name",info.name);
editor.commit();
Intent intent = new Intent(context, MapsFragment.class);
intent.putExtra("name",info.name);
context.startActivity(intent);>
}
});
return view;
}
I want to pass to mapfragment using intent but it redirect to MainActivity instead of MapFragment. How can I stop transferring to MainActivity?
Thank you.

A common pattern to passing a value to a Fragment is using newInstance method. In this method you can set Argument to fragment as a means to send the value.
First, create the newInstance method:
public class YourFragment extends Fragment {
...
// Creates a new fragment with bus_name
public static YourFragment newInstance(String busName) {
YourFragment yourFragment = new YourFragment();
Bundle args = new Bundle();
args.putString("bus_name", busName);
yourFragment.setArguments(args);
return yourFragment;
}
...
}
Then you can get the value in onCreate:
public class YourFragment extends Fragment {
...
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Get the value from arguments
String busName = getArguments().getString("bus_name", "");
}
...
}
You can set the value to the Fragment from your activity with:
FragmentTransaction fragTransaction = getSupportFragmentManager().beginTransaction();
YourFragment yourFragment = YourFragment.newInstance("bus_name_value");
fragTransaction.replace(R.id.fragment_place_holder, yourFragment);
fragTransaction.commit();
You can use the above codes to send the value in Fragment initialization.
If you want to set the value to the already instantiated fragment, you can create a method then invoke the method to set the value:
public class YourFragment extends Fragment {
...
public setBusName(String busName) {
// set the bus name to your fragment.
}
...
}
Now, In the activity, you can invoke it with:
// R.id.yourFragment is the id of fragment in xml
YourFragment yourFragment = (YourFragment) getSupportFragmentManager()
.findFragmentById(R.id.yourFragment);
yourFragment.setBusName("bus_name_value");

You cannot pass an intent to a Fragment. Try using a Bundle instead.
Bundle bundle = new Bundle();
bundle.putString("name", info.name);
mapFragment.setArguments(bundle)
In your Fragment (MapsFragment) get the Bundle like this:
Bundle bundle = this.getArguments();
if(bundle != null){
String infoName = bundle.getString("name");
}

As guys mentioned before:
1. Use callback or just casting on your context (your activity must handle changing fragments itself).
2. To change fragments use activity's FragmentManager - intent is used to start another activity.
Fragments Documentation

How can pass array list object from an activity to fragment in android

I am storing some values in array list now i want to pass the same array list object to fragment from an activity. So how can i send the array list object from an activity and receive the same object in fragment.

Try this code in your activity, It is a code snippet from my working application.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
yourArrayList.add("test");
yourArrayList.add("test2")
Bundle bundle = new Bundle();
bundle.putStringArrayList("arrayList", yourArrayList);
yourFragment yourFragment = new yourFragment();
yourFragment.setArguments(bundle);
fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.add(R.id.main_container, yourFragment);
fragmentTransaction.commit();
}
In your fragment you can access the value like this
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
ArrayList<String> values = getArguments().getStringArrayList("arrayList");
}

pass activity should follow this lines
Bundle bundle = new Bundle();
bundle.putStringArrayList("valuesArray", namesArray);
namesFragment myFragment = new namesFragment();
myFragment.setArguments(bundle);
fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.add(R.id.main_container, myFragment);
fragmentTransaction.commit();
get Fragment inside follow this lines
ArrayList<ObjectName> arraylist = extras.getParcelableArrayList("valuesArray");

You can do this by following the usual way of Fragment-Activity communication. That is:
1) Declare a public interface within your Fragment class.
2) Inside this interface declare a getter method for your list.
3) Make your respective Activity implement this interface.
4) Inside your Fragment, do this:
#Override
public void onAttach(Context context) {
super.onAttach(context);
YourInterfaceType activity = (YourInterfaceType) context;
List<> yourList = activity.getMyList();
}
To make it more clear:
Your activity will be as follows:
public class MyActivity extends Activity implements YourInterfaceType{
#Override
public void getMyList(){
return yourList;
}
}

just put your array with setargument in Actiivty and get Array
getArgument in fragment.
Activity
Bundle bundle = new Bundle();
bundle.putStringArrayList("valuesArray", namesArray);
namesFragment myFragment = new namesFragment();
myFragment.setArguments(bundle);
fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.add(R.id.main_container, myFragment);
fragmentTransaction.commit();
fragment
ArrayList<Model> values = getArguments().getStringArrayList("valuesArray");

How to move from an activity to a fragment in Android?

May you assist by telling me the best way to moves from an activity to a fragment. This is what I have so far but it doesnt seem to work.
This is how I am calling the function(getCategory)
private void selectItem( int group, int usage)
{
if (!shown) return;
classificationGroup = group;
((DashboardActivity)getActivity()).getCallCategory(classificationGroup);
}
And in the activity I am trying to move to a fragment
public Fragment getCallCategory(int position) {
return new CallLogsFragment();
}

The standard pattern for creating fragments looks like this:
Inside your fragment class (make sure to import the android.support.v4.app.Fragment):
public class MyFragment extends Fragment {
public static final String TAG = "MyFragment";
private int position;
// You can add other parameters here
public static MyFragment newInstance(int position) {
Bundle args = new Bundle();
// Pass all the parameters to your bundle
args.putInt("pos", position);
MyFragment fragment = new MyFragment();
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.position = getArguments().getInt("pos");
}
}
Inside your activity:
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Add your parameters
MyFragment fragment = MyFragment.newInstance(10);
// R.id.container - the id of a view that will hold your fragment; usually a FrameLayout
getSupportFragmentManager().beginTransaction()
.add(R.id.container, fragment, MyFragment.TAG)
.commit();
}
}
When you want to access public methods of your fragment instance, use FragmentManager#findFragmentByTag(String tag) to find your instance of fragment:
MyFragment fragment = (MyFragment) getSupportFragmentManager().findFragmentByTag(MyFragment.TAG);
if(fragment != null){
// Do something with fragment
}
For a more detailed explanation, I suggest you read the official docs on fragments: https://developer.android.com/guide/components/fragments.html

how fragment can get data from parentActivity?

I have 2 activities MainActivity and DetailActivity, if I click in the ListView in MainActivity will intent to DetailActivity with content "id", in DetailActivity I have 2 fragment (TabLayout-ViewPager).
My question is: How can fragment get "id" from that intent above???

Fragment in android
,If Android decides to recreate your Fragment later, it's going to call the no-argument constructor of your fragment. So overloading the constructor is not a solution.for more detail please read this stack overflow answer
private int mId;
private static final String ID = "id";
public static DetailsFragment newInstance(int id) {
DetailsFragment fragment = new DetailsFragment();
Bundle args = new Bundle();
args.putInt(ID, id);
fragment.setArguments(args);
return fragment;
}
get values in oncreate method
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null)
//mId is variable which contain (YourActivity)MainActivity value.you can use in fragment.
mId = getArguments().getInt(ID);
}
//call in your YourActivity(MainActivity) in oncreate method
int id = yourid;
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,DetailFragment.newInstance(id)).commit();

from Android Developer's Fragment Page
DetailsFragment f = new DetailsFragment();
// Supply index input as an argument.
Bundle args = new Bundle();
args.putInt("index", index);
f.setArguments(args);
// add fragment to the fragment manager's stack

Like #cricket_007 says, create a factory method in your fragment and pass the data through bundle arguments consider the example below
public static YourFragment newInstance(Bundle args) {
Yourfragment fragment = new YourFragment();
Bundle bundle = args;
// Or if your args is a variable data for example a string
// use Bundle bundle = new Bundle(); bundle.putString("extra_name",value);
// Now set the fragment arguments
fragment.setArguments(bundle);
return fragment;
}
And now anywhere in your fragment you can do
Bundle args = getArguments();
// and access your extra by args.getString("extra_name"); ...

Should An Actvity Pass Fields To Fragment Or Should The Fragment Initialize It?

I have a ListFragment that's using a DAO object. The DAO object queries a DB and returns a list of strings that I will display in the ListView. My question is - should the activity pass the DAO object to the fragment, or should the fragment initialize it on its own?
Activity:
Bundle bundle = new Bundle();
bundle.putParcable("dao", myDao);
FragmentClass frag = new FragmentClass();
frag.setArguments(bundle);
Or in Fragment:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
myDao = new MyDao(getActivity());
}

I think first case "Passing field to fragment" is better. As #Campiador commented, if your case is to retain the FragmentClass for all the time then you can initialise the fields from fragment
Activity:
Bundle bundle = new Bundle();
bundle.putParcable("dao", myDao);
FragmentClass frag = new FragmentClass();
frag.setArguments(bundle);
Fragment :
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyDao mDao = getArguments().getParcelable("dao");
}
Hope this will help you