Sure, its very possible and easy to do with B4A. Check out
Custom Dialogs
You can also create it manually,
Add a panel
-Add your image as a background
-Use QR Generator to create your QRCode and place it on the panel
-Use a lable or another panel and insert the close icon image and position it well.
-Send this panel to back or make it invisible (To call it, make it visible or bring it to front) depending on the one you use.