Move newInstance method before constructor #8

The static newInstance() method of Fragments is a common way to create new Fragment instances. The same pattern can be used for Activities to build an Intent in a type safe way, namely newIntent(). Those building functions replace the constructors.

public static class MyFragment extends Fragment {

  public MyFragment() { }  // Required empty constructor

  public static MyFragment newInstance(String foo, int bar) {
    MyFragment f = new MyFragment();
    Bundle args = new Bundle();
    args.putString(ARG_FOO, foo);
    args.putInt(ARG_BAR, bar);
    f.setArguments(args);
    return f;
  }

You can then access this data at a later point:

@Override
public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  Bundle args = getArguments();
  if (args != null) {
    // Use initialisation data
  }
}

There aren't many use cases for public static methods in Java other than initializer helper methods. Utils methods are also public static but they normally exist in util classes where all methods are public static. That's the reason why it is safe to move all methods with this signature above the constructor.