Display data from a class from an secondary .cs external to main.cs in WPF XAML

I'm trying to display in XAML a value of a property of a class contained in "Call.cs".

public class call{
.
.
  1InputData InputData = 1InputData.Default();
  public void main(){
    InputData.X.A[0]=99;
 }

I put in main.cs:

 var run1 = new Call();
 run1.main();
 var show = new Binding("run");

 show.Mode = BindingMode.OneWay;
 show.Source = run1;

And in my XAML:

<TextBlock HorizontalAlignment="Center" TextWrapping="Wrap" Text="{Binding run1.InputData.A.B[0]}" VerticalAlignment="Center" Grid.Row="1" Grid.Column="2"/>

But the context is not being recognized. I dont want to set a DataContext for the full WPF Window, because I will need to access to more than one origin to bind data.

The window that will display this Data is a secondary window called from a button in main window. (Just saying in case this is relevant).

There is a way to do it?

Thank you!