Hi @Chi ,
Currently there's no way to directly copy just a Custom container from the designer to another project. You have to import an entire gui from another .touchgfx file. I think it's something we'd like to make easier.
Your only option is to create it again, or to simply copy the generated code to your new project and rename the class (From MyCustomContainerBase to something else) and use that as code in your concrete views. If it's not too complex, i'd remake it. Or you can snip the code from the .touchgfx file if you can identify it. But i will bring this topic up again!
Thanks,
Best regard,
Martin