With v18.2, XAF users will get easy access to a much larger icon set from the DevExpress Image Gallery and new SVG images for use with XAF’s WinForms UI. To browse all new and previously available images, XAF’s Model Editor ships with a new Image Picker (used for both SVG and PNG image selection). Images from the DevExpress.ExpressApp.Images assembly are no longer used in XAF apps. We will retain this assembly for 1-2 release cycles for backward compatibility and then remove completely.
Refer to the XAF - Improved Image Library Integration, SVG support and other important changes (v18.2) blog post for more information.
These pictures are available with the source code DevExpress.Images assembly from the "<Your DevExpress installation folder>\DevExpress 1X.X\Components\Sources\DevExpress.Images" directory. For instance, it's "C:\Program Files (x86)\DevExpress 15.1\Components\Sources\DevExpress.Images" on my machine.
You can include these images into your XAF project using the 'File Image Source'. See Add and Override Images for more information. Please take special note of the 'Rules for Image Files' section. At the moment, it is impossible to use the DevExpress.Images assembly via the 'Assembly Resource Image Source'.
How to use the DevExpress.Images Assembly in XAF - one of our customers also wrote a tool that simplifies this process.