Yes, there are already model can do that. I use DeepSeek V4 Flash and it's Free.
First it can write a sub BuildUI (for example) that initialize the views with size, position, color, etc and add to the layout or parent.
You can create 2 examples of bal layout files and let the IDE convert them to json layouts.
Then tell the model based on the converted json layouts files, learn the pattern and convert the code in BuildUI to apply to the json layouts files.
Once it is done, let the IDE convert the json layouts back to bal binary format.
After that it will know how to do for the rest.
Note, at the beginning it may create json layouts that failed to convert to bal but if you tell it that the layouts were wrong and fix them for few times, it will see the correct pattern and create correct json layout from there onwards.