RadioSet in ABL --> RadioButtons in .Net

Hello, everybody. I want to use tabControl in a frame that shows a variety of options to user. I decided to abandon the static frame in .p program and create a new form in DevStudio. 

I had a problem when binding RadioButtons with table field. For binding I use ProBindingSource and there no problem with textboxes.

So I have to keep this option in the frame:

DEFINE FRAME DIALOG-1
...
   div_vars.eq_comm                          AT ROW 8.2 COL 40 COLON-ALIGNED
    VIEW-AS RADIO-SET
    RADIO-BUTTONS
    "File",0,
    "Web-service",1
     HORIZONTAL
     SIZE  30 BY 1
    TOOLTIP "Exchange type with Equation"    

I realized that I can not directly binding radiobutton with integer field div_vars.eq_comm. 

As a workaround, I decided to pull a separate textbox text_eq_comm (in ellipse) and bind it with div_vars.eq_comm.

Of course, it is shown in the form solely for test purposes.

And now I should be able to check text_eq_comm:Text on the event FormLoad (I thought so). But the Text property throughout load form is blank:

	METHOD PRIVATE VOID div_vars_Load( INPUT sender AS System.Object, INPUT e AS System.EventArgs ):
	    
        MESSAGE "Load~n"
                THIS-OBJECT:text_eq_comm:Text VIEW-AS ALERT-BOX. 
        IF text_eq_comm:Text = "0"
        THEN file_opt:Checked = TRUE.
        ELSE IF text_eq_comm:Text = "1"
        THEN serv_opt:Checked = TRUE.
	END METHOD.

When I go to the second tab and call message by double-clicking on this textbox - Text property is returned correctly.

	@VisualDesigner.
	METHOD PRIVATE VOID text_eq_comm_DoubleClick( INPUT sender AS System.Object, INPUT e AS System.EventArgs ):
		
		MESSAGE text_eq_comm:Text VIEW-AS ALERT-BOX.

	END METHOD.

What have I missed?

I assume that the field must be of logiсal type to be able to bind it directly with the radiobutton. Perhaps there are other variants  of binding the radio buttons with non-logical fields?

Thanks!