getArgument is NULL, why?

Question

I am trying to pass values through a Bundleusing setArguments() from an activity to another class extends Fragment when I press one of the listed items in a ListView.

As shown below, I used a Log.i statement to know if the Bundle received is null or not. Unfortunately, it is always null and consequently, no data shows on the designated TextView of the class that extends Fragment. What I am missing or what is wrong with the code.

FragmentClass:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    // TODO Auto-generated method stub

    View view = inflater.inflate(R.layout.fragmentclasslayout, null);
    return view;
}

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onActivityCreated(savedInstanceState);

    if (getArguments() != null) {
        Log.i(TAG, "getArgument is not null");
        int value = getArguments().getInt("pos");           
        TextView tv = (TextView) getView().findViewById(R.id.tvID);
        tv.setTextSize(value);
        tv.setText("size = "+value*10);
    }else {
        Log.i(TAG, "getArgument is null");
    }
}

MainClass_implements_onItemSelectedListener:

setContentView(R.layout.mainactivity);

    ListView mListView = (ListView) findViewById(R.id.list);
    ArrayAdapter<String> mArrayAdapter = new ArrayAdapter<String>(getApplicationContext(),
            R.layout.listviewlayout, R.id.tv, string);
    mListView.setAdapter(mArrayAdapter);
    mListView.setOnItemSelectedListener(this);
}

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position,
        long id) {
    // TODO Auto-generated method stub

    Fragment f = new FragmentClass();
    Bundle bundle = new Bundle();

    bundle.putInt("pos", (position+1));
    FragmentClass fc = new FragmentClass().newInstance(bundle);
    //f.setArguments(bundle);

    FragmentTransaction t =
            getFragmentManager().beginTransaction();
            t.replace(R.id.fragment00ID, f);
            t.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
            t.addToBackStack(null);
            t.commit();
}

mainActivity_layout:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
tools:ignore="MergeRootFrame">

<ListView
    android:id="@+id/list"
    android:layout_width="100px"
    android:layout_weight="1"
    android:layout_height="match_parent" />
<fragment
    android:name="com.example.fragmentwithlistview.FragmentClass"
    android:id="@+id/fragment00ID"
    android:layout_toRightOf="@+id/list"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:layout_weight="4" />

FragmentClass_layout:

<FrameLayout 
xmlns:android="http://schemas.android.com/apk/res/android"    
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
tools:ignore="MergeRootFrame"
android:background="#FFFFFF">

<TextView
    android:id="@+id/tvID"
    android:textColor="#000000"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"/>

Answer 1

Better use a static method for instantiating:

public class FragmentClass extends Fragment {

  public static FragmentClass newInstance(Bundle b) {
    FragmentClass fragment = new FragmentClass();
    fragment.setArguments(b);

    return fragment;
  }

  public View onCreateView(LayoutInflater inflater, ViewGroup container,
          Bundle savedInstanceState) {
      View view = inflater.inflate(R.layout.fragmentclasslayout, null);

      if (getArguments() != null) {
          Log.i(TAG, "getArgument is not null");
          int value = getArguments().getInt("pos");           
          TextView tv = (TextView) view.findViewById(R.id.tvID);
          tv.setTextSize(value);
          tv.setText("size = "+value*10);
      } else {
          Log.i(TAG, "getArgument is null");
      }

      return view;
  }
}

Then simply call that method and pass the arguments-bundle as a parameter:

Bundle bundle = new Bundle();
bundle.putInt("pos", (position+1));
FragmentClass f = FragmentClass.newInstance(bundle);

Also, don't use onActivityCreated for fetching the arguments in your FragmentClass, use onCreateView or if required onStart or onResume. Have a look at fragment-lifecycles: http://developer.android.com/guide/components/fragments.html#Lifecycle

Answer 2

You can use in passing Activity

Bundle bundle = new Bundle();
    bundle.putString("model", strDeckNumber);

                    final FragmentTransaction t = getActivity().getSupportFragmentManager().beginTransaction();
                    Frag1 newFragment = new Frag1();
                    newFragment.setArguments(bundle);
                    t.replace(R.id.fragment_container, newFragment);
                    t.addToBackStack(TAG);
                    t.commit();

Receiving Fragment

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {

            strSeriesNumber = getArguments().getString("model");
}