Error:Execution failed for task ':app:compileDebugJavaWithJavac'.
> android.databinding.tool.util.LoggedErrorException: Found data binding errors.
  ****/ data binding error ****msg:Identifiers must have user defined types from the XML file. viewmodel is missing it
 file:C:UsersjacopDocumentsandroidprojectscarBookappsrcmainreslayoutactivity_main.xml
  loc:18:24 - 18:32
  **** data binding error ****

public class MainActivity extends AppCompatActivity implements LifecycleOwner {

    public MainViewModel viewModel;

public class MainViewModel extends ViewModel {

    private LatLng origin;

public LatLng getOrigin() {
        return origin;
    }

<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context="jacopo.com.gpspath.MainActivity">
    <data>
        <variable name="viewModel" type="jacopo.com.carbook.MainViewModel" />
    </data>
    <TextView
        android:id="@+id/text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@{viewModel.origin.latitude}"/>
</layout