For all barcode grid symbologies, the XDimension property defines the narrow element width for the symbol in millimeters. The property value is used when Stretch.None is used to specify the width of the symbology. The nominal value for every barcode is set as its default value.
Here is a comparison between two barcodes:
In XAML:
<ig:XamQRCodeBarcode x:Name="barcode1" Data="Code Data" Stretch="None" XDimension="2" />
<ig:XamQRCodeBarcode x:Name="barcode2" Data="Code Data" Stretch="None" XDimension="4"/>
In C#:
var barcode1 = new XamQRCodeBarcode();
barcode1.Data = "Code Data";
barcode1.Stretch = BarcodeStretch.None;
barcode1.XDimension = 2;
var barcode2 = new XamQRCodeBarcode();
barcode2.Data = "Code Data";
barcode2.Stretch = BarcodeStretch.None;
barcode2.XDimension = 4;