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Android

Sahit penmatcha
Sahit penmatcha
4,555 Points
Posted by Sahit penmatcha
Sahit penmatcha
4,555 Points

Passing Data from Activity to Fragment Null Object Reference

I am creating an application where the user clicks a "plus" button on the fragment which takes them to a new activity where they enter data. After clicking "save" on this data, the activity should close and the fragment should display this data. I am getting this error when trying to pass the information from the activity to the fragment:

                                                                                   java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.Bundle.getString(java.lang.String, java.lang.String)' on a null object reference
                                                                                 at com.example.sahitpenmatcha.scagenda.Fragments.ClassesFragment.onCreateView(ClassesFragment.java:44)
                                                                                 at android.support.v4.app.Fragment.performCreateView(Fragment.java:1974)
                                                                                 at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067)
                                                                                 at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1252)
                                                                                 at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:742)
                                                                                 at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1617)
                                                                                 at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:517)
                                                                                 at android.os.Handler.handleCallback(Handler.java:739)
                                                                                 at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                                 at android.os.Looper.loop(Looper.java:158)
                                                                                 at android.app.ActivityThread.main(ActivityThread.java:7224)
                                                                                 at java.lang.reflect.Method.invoke(Native Method)
                                                                                 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
                                                                                 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)

This is the Activity the Data is coming from...

switch (item.getItemId()) { // Respond to the action bar's Up/Home button case android.R.id.home: finish(); return true; case R.id.save_button: //add saving code here to save options classNames[0] = mEnterClassName.getText().toString();

        Bundle bundle = new Bundle();
        bundle.putString("STRING_KEY", classNames[0]);
        mClassesFragment.setArguments(bundle);

        finish();
        android.support.v4.app.FragmentTransaction fragmentTransaction =
                getSupportFragmentManager().beginTransaction();
        fragmentTransaction.add(mClassesFragment, "classFrag");
        fragmentTransaction.commit();



        return true;
}

This is the Fragment the data needs to get to...

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

className = getArguments().getString("KEY_STRING","Class");


((AppCompatActivity)getActivity()).getSupportActionBar().setTitle(R.string.classes_title);
View view = inflater.inflate(R.layout.fragment_classes, container, false);
mRecyclerView = (RecyclerView) view.findViewById(R.id.timeRecyclerView);


adapter = new ClassAdapter(getActivity());

mRecyclerView.setLayoutManager(new LinearLayoutManager(this.getActivity()));
mRecyclerView.setAdapter(adapter);
ItemTouchHelper.Callback callback = new ItemSwipeHelper(getContext(), adapter);
ItemTouchHelper helper = new ItemTouchHelper(callback);
helper.attachToRecyclerView(mRecyclerView);

FloatingActionButton fab = (FloatingActionButton) view.findViewById(R.id.fab);
assert fab != null;
fab.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        adapter.add(0);
    }
});

adapter.setClassTitle(className);

// Inflate the layout for this fragment
return view;

}

Sahit penmatcha
Sahit penmatcha
4,555 Points
Sahit penmatcha
Sahit penmatcha
4,555 Points

EDIT: I changed "KEY_STRING" to "STRING_KEY" so they are equal, but still same error