Handle Back Press in Fragments

BaseActivity.Java

protected OnBackPressedListener onBackPressedListener;

//...

public void setOnBackPressedListener(OnBackPressedListener onBackPressedListener) {
    this.onBackPressedListener = onBackPressedListener;
}

//...

@Override
public void onBackPressed() {
    if (onBackPressedListener != null)
        onBackPressedListener.doBack();
    else
        super.onBackPressed();
}

Fragment1.java

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    activity = getActivity();

    ((BaseActivity)activity).setOnBackPressedListener(new BaseBackPressedListener(activity));

    View view = ... ;
    //stuff with view

    return view;
}

OnBackPressedListener.Java

public interface OnBackPressedListener {
    public void doBack();
}