How to fix Resource versus Resources error in Xamarin - Visual Studio - visual-studio

Question

I have a very simple Xamarin Android app. It has a text box and a button. Here's the activity_main.axml file in Resources.Layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:text="0"
android:textSize="50sp"
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/txtNumber"
android:layout_marginBottom="20dp"
android:layout_marginTop="20dp" />
<Button
android:text="Get Number"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/btnAutoGenerate" />
In the Solution Explorer I have Assets and Resources.
Under Resources is layout and under layout is activity_main.axml
Not complex at all.
In MainActivity.cs, the OnCreate procedure is this:
[Activity(Label = "#string/app_name", Theme = "#style/AppTheme", MainLauncher = true)]
public class MainActivity : AppCompatActivity
{
protected override void OnCreate(Bundle savedInstanceState)
{
TextView txtNumber;
base.OnCreate(savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.activity_main);
txtkNumber = FindViewById<TextView>(Resource.Id.txtNumber);
FindViewById<Button>(Resource.Id.btnAutoGenerate).Click += (o, e) =>
txtNumber.Text = btnAutoGenerate_Click(o, e);
}
I'm not sure where Resource is defined (as in the xml it's Resources) but even though at first this compiled with no problem now I get the error: the name "Resource" does not exist in the current context.
Because when the default files are first generated, it is
SetContentView(Resource.Layout.activity_main);
even though the "Resource.Layout" is pointing to Resources.layout. Not sure why.