<data>

        <variable
           name="model"
           type="com.iguanafix.jorgegonzalez.contacts.viewmodel.ContactViewModel"/>

        <variable
            name="dto"
            type="com.iguanafix.jorgegonzalez.contacts.dtos.Contact"/>
    </data>

                   .
                   .
                   .

    <include
     android:id="@+id/content_detail"
     layout="@layout/content_contacts_detail"
     bind:dto="@{model.getmContact}"
     android:visibility="gone"/>

<data>
        <import type="java.lang.String"/>

        <variable
            name="contact"
            type="com.iguanafix.jorgegonzalez.contacts.dtos.Contact"/>
    </data>
                   .
                   .
                   .

           <TextView
            android:id="@+id/contact_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginBottom="8dp"
            android:layout_marginEnd="8dp"
            android:layout_marginStart="8dp"
            android:text="@{String.format(@string/fullname, contact.getmLastName, contact.getmFirstName)}"
            app:layout_constraintBottom_toBottomOf="@+id/thumb"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintHorizontal_bias="0.0"
            app:layout_constraintStart_toEndOf="@+id/thumb"
            app:layout_constraintTop_toTopOf="@+id/thumb" />

public class ContactViewModel extends ViewModel {
    private Contact mContact;
    private MutableLiveData<ContactApiResponse> mLiveListContacts = new MutableLiveData<>();
    private MutableLiveData<ContactApiResponse> mLiveContact = new MutableLiveData<>();
    private ContactsRepository mRepository = new ContactsRepository();

    public Contact getmContact() {
        return mContact;
    }

    public void setmContact(Contact mContact) {
        this.mContact = mContact;
    }

    public void loadContactList(){
        mRepository.getConstactList(mLiveListContacts);
    }

    public LiveData<ContactApiResponse> getListContacts(){
        return mLiveListContacts;
    }

    public void loadContact(String contactId){
        mRepository.getConstact(mLiveContact, contactId);
    }

    public LiveData<ContactApiResponse> getContact(){
        return mLiveContact;
    }

}

public class Contact {
    @SerializedName("user_id")
    private String mUserId;
    @SerializedName("created_at")
    private String mCreatedAt;
    @SerializedName("birth_date")
    private String mBirthDate;
    @SerializedName("first_name")
    private String mFirstName;
    @SerializedName("last_name")
    private String mLastName;
    @SerializedName("phones")
    private ArrayList<Phone> mPhones;
    @SerializedName("thumb")
    private String mThumb;
    @SerializedName("photo")
    private String mPhoto;
    @SerializedName("addresses")
    private ArrayList<Address> mAddresses;

              .
              .
              .
        geters y seters
}