There are special fonts you can use.
This one for example: Free Barcode Font - Code 39 - Not a demo, COMPLETELY free
You should first copy FREE3OF9.ttf to \Windows\Fonts.
Afterwards you should change the font of a textbox or label (flb is a FormLib object):
B4X:
Sub App_Start
Form1.Show
flb.New1("form1",B4PObject(1))
TextBox1.FontSize = 40
flb.ChangeFont("textbox1","Free 3 of 9")
TextBox1.Text = "*2141*"
End Sub
thanks.
should have mentioned I'm after doing this on a Smartphone, and UPC-A is probably the most important.
There are some barcode DLLs but I didn't want to pay the $400+ if I could avoid it (I want to make a free app!)