Android - How To Pass Data From Activity To Fragment?

I need to pass data from activity to fragment. I know I can use bundle , but once I passed data,I can't send data without calling and creating fragment again. In my activity, some

Solution 1:

Create one interface in your Activity and pass your data via the interface to the fragment. Implement that interface in your fragment to get data.

For example

MainActivity.class

publicclassMainActivityextendsAppCompatActivity {

    DataFromActivityToFragment dataFromActivityToFragment;

    @OverrideprotectedvoidonCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        FragmentAfr=newFragmentA();
        FragmentManagerfm= getFragmentManager();
        dataFromActivityToFragment = (DataFromActivityToFragment) fr;
        FragmentTransactionfragmentTransaction= fm.beginTransaction();
        fragmentTransaction.replace(R.id.fragment_place, fr);
        fragmentTransaction.commit();


        finalHandlerhandler=newHandler();

        finalRunnabler=newRunnable() {
            publicvoidrun() {
                dataFromActivityToFragment.sendData("Hi");
            }
        };

        handler.postDelayed(r, 5000);


    }

    publicinterfaceDataFromActivityToFragment {
        voidsendData(String data);
    }
}

FragmentA.class

publicclassFragmentAextendsFragmentimplementsMainActivity.DataFromActivityToFragment {

    TextView text;

    @Nullable@OverridepublicViewonCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.content_main, null);
        text = (TextView) rootView.findViewById(R.id.fragment_text);

        return rootView;
    }

    @OverridepublicvoidonViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
    }

    @OverridepublicvoidsendData(String data) {
        if(data != null)
        text.setText(data);
    }
}

activity_main.xml

<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical" ><LinearLayoutandroid:id="@+id/fragment_place"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="horizontal"></LinearLayout></LinearLayout>

content_main.xml

<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"><TextViewandroid:id="@+id/fragment_text"android:layout_width="wrap_content"android:layout_height="wrap_content" /></LinearLayout>

In above example I have taken Runnable just to send data with delay of 5 seconds after creation of fragment.

Solution 2:

Fragment object is just like other objects.Like String , you can invoke methods of string object, str.charAt(0) ,str.toUpperCase() etc. Just create a function in fragment, put your code there and call the function along with values

Inside Activity {
  fragDemoObject.doWhatYouWant("this is passed as string object to fragment");
}

Inside FragmentDemo{
  void doWhatYouWant(String input){
     System.out.println(input);
    // do what else you want to do with code
  }

}

Solution 3:

Actually your question is not related to:

I need to pass data from activity to fragmenet .I know I can use bundle , but one i've passed data , I cant send anymore data without calling and creating fragment once more .

The real one is this:

in my activity , some thing may be changed and I need to notify my fragment from these changes without recreating fragment.

how can I do so ?

In this case I would store the fragment in the activity as reference and I would call a function, an interface implementation inside the fragment.

Something like this:

In Activity:

SomeEventListener myFragment  ;

yourFragmentCreationMethod(){
 if(myFragment == null){
    myFragment  = newMyFragment(maybeParamsHere);
  }
}

yourNotificationMethod(){
   myFragment .onEventHappent(param);
}

// declare an interface: - separate filepublicinterfaceSomeEventListener
{
    voidonEventHappent(param);
}

// implement the interface in Fragment - separate filepublicclassMyFragmentextendsFragmentimplementsSomeEventListener{
    // add a constructor what you likepublicvoidonEventHappent(param){
           /// ... your update
    }
}

The interface it will help you at testing only.

Solution 4:

The host activity can deliver messages to a fragment by capturing the Fragment instance with findFragmentById(), then directly call the fragment's public methods.

In your fragment - MyFragment, create a public method

publicvoidmyFragmentDataFromActivity(int passedDataFromActivity){

// do your stuff

}

In your activity to pass an integer value say, 100 :

get MyFragment instance using getSupportFragmentManager or getFragmentManager by providing id/tag/position. Then call the public method in MyFragment instance.

MyFragment myFragment = (MyFragment) getSupportFragmentManager.getFragmentById(id);

myFragment.myFragmentDataFromActivity(100);

You can also use getFragmentByTag(tag), getFragments().get(position) instead of getFragmentById(id) to get fragment instance.

read more about this

Solution 5:

For notify fragment with some data after it's created, can be done using some Communicator, or you can always pass the data with bundle in creation time... For example:

publicinterfaceFragmentCommunicator {

voidupdateDataToFragment(List<Parcelable> data);

} then in your fragment implement this interface and calling it from the activity for example as:`

Fragmentfragment= mSectionsPagerAdapter.getRegisteredFragment(i);
            if (fragment instanceof FragmentCommunicator) {
                FragmentCommunicatorfragmentCommunicator= (FragmentCommunicator) fragment;
                fragmentCommunicator.updateDataToFragment(data);

        }`

This should works for your case...