Show a barcode

I need to edit a PDF which has a text field that gets filled with the Code-128 plain font (it's a font that shows a barcode instead of text), if I fill the field manually through AdobeReader the barcode appears correctly, but if I fill the field with the Radaee Android SDK the barcode doesn't appears (it appears some text and symbols instead).
I'm setting the text of the field with :

annotation.SetEditText("myfieldvalue")

How do I make a barcode appear in that field?

You shall add the font in your app's resources and add it in the global definition.
Add the font resource to the page and set it as font to the text field.
Note: I suggest you to check the font's distribution license, even if are free many fonts need to pay a distribution license within applications.

If you want, we may check the font for you: let create a support ticket in the support area.

Regarding this: "add the font in your app's resources and add it in the global definition" i know how to add the fotn to the app resources, but what you mean by "add in the global definition?" can you provide the code for it?

I see that the Page object has an AddResFont method, however it doesn't accept a font resource but a "DocFont", how do I properly create a DocFont object? Can you nprovide the code for it?
I already checked you documentation and also the Android Master app but I cannot find any example of it.
Thank you