1)Don’t call views Fragments. Fragments are a separate concept in Android, and your code will confuse everyone.

2)If you created that view as a subview of your custom view, you’d use findViewById, not context.findViewById. Because the view isn’t in the context, its one of your subviews.

Thanks to all!!!
I’ve found a way to connect the xml to the View class:

ayoutInflater inflater = (LayoutInflater)this.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        inflater.inflate(R.layout.fragment_players, null, false);

Trying to access components via findByViewId and get null
The problem is in this line:

(I cannot connect my viewxml to the class)

// HERE I GET NULL
    **_addButton     = context.findViewById(R.id.buttonAdd);**

I have an activity:
with this OnCreate:

MainActivity class

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);
}

I have a custom view I call in my MainActivity
MainActivity xml

   <com.example.myemptyapplication.PlayersFragment
        android_id="@+id/fragment_container_view_players"
        android_layout_weight="1"
        android_layout_width="match_parent"
        android_layout_height="match_parent"
        android_layout_marginLeft="10px"/>

In ‘PlayersFragment’ I’ trying to access

PlayersFragment extends View

@RequiresApi(api = Build.VERSION_CODES.O)
    public PlayersFragment(Context context, AttributeSet attSet) {
        super(context, attSet);

 protected void onFinishInflate() {
        super.onFinishInflate();
    // HERE I GET NULL
        **_addButton     = context.findViewById(R.id.buttonAdd);**
    }

Tried to get components in a custom view