How to access Fragment's child views inside fragment's parent Activity?

Question

I have a supported fragment activity which will load diff fragments. The fragment has some textView with id = "score" and I want to get its handle but findViewById for score's textView returns null. Why so?

textView is placed in fragment

public class MyActivity extends  extends ActionBarActivity
        implements NavigationDrawerFragment.NavigationDrawerCallbacks{

   private TextView scoreBoardTextView = null;

   protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
     setContentView(R.layout.activity_home);
     mNavigationDrawerFragment = (NavigationDrawerFragment)
                getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
     scoreBoardTextView = (TextView) findViewById(R.id.score); //this returns null
  }

    @Override
    public void onNavigationDrawerItemSelected(int position) {
      //set fragment    
    }

}

Answer 1

Note:

Directly accessing fragment's views outside fragment is not a good idea. You should use fragment callback interfaces to handle such cases and avoid bugs. The following way works but it is not recommended as it is not a good practice.

---

If you want to access the TextView of Fragment inside its parent Activity then you should define a method inside your Fragment class like this:

public class MyFragment extends Fragment {

    TextView mTextView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.activity_main, container, false);
        mTextView = (TextView) view.findViewById(R.id.textView1);
        return view;
    }

    public void setTextViewText(String value){
        mTextView.setText(value);
    }


}

Now you can use this inside your Activity like this:

myFragment.setTextViewText("foo");

here myFragment is of type MyFragment.

If you want to access the whole TextView then you can define a method like this inside MyFragment.java:

public TextView getTextView1(){
    return mTextView;
}

By this you can access the TextView itself.

Hope this Helps. :)

Answer 2

It is possible with following way:

Keep reference of inflated view in the Fragment like this :

public class MyFragment extends SherlockFragment{

MainMenuActivity activity;
public View view;
public MyFragment(){
}

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

    if ( getActivity() instanceof MainMenuActivity){
        activity = (MainMenuActivity) getActivity();
    }

    view = inflater.inflate(R.layout.aboutus, container, false);        
    return view;
}

}

Create a function in the Activity, like this:

 public class MainMenuActivity extends SherlockFragmentActivity {

 SherlockFragment fragment = null;

 public void switchContent(SherlockFragment fragment) {     
    this.fragment = fragment;
    getSupportFragmentManager()
    .beginTransaction()
    .replace(R.id.mainmenu, fragment)
    .commit();

    invalidateOptionsMenu();
}

Its purpose is to keep reference of current fragment. Whenever you wanna switch fragment, you call above function, like this (from fragment):

activity.switchContent( new MyFragment_2());

Now you've current fragment reference. So you can directly access Fragment's views in Activity like this: this.fragment.view