问题
I am trying to design a UI based on Use cases, activity diagrams and sequence diagrams. is it necessary to design the Class diagrams for the UI design?
回答1:
No diagrams are needed to write the code, but it would make the life hell for a 3rd person to understand the application and work on it.
As famous English proverb, images are better than 1000 words. UML diagrams are one of the easy and standard ways to document the application architecture.
If you are building the application for your own sake, then it might be an excuse not to use UML otherwise I would suggest to have the required UML diagrams (Class diagrams, sequence diagrams and Entity relationship diagrams, if applicable (Datamodel)).
回答2:
I agree with the accepted answer, and will add that UML diagrams are a form of documentation. As such, they are only of use if there is an intended recipient - could be another team, or yourself at some point in the future (remember, most coding work is maintenance), or a design authority if you need to get approval of your design before you write the code.
This is assuming you're not intending to do code generation from your model, which EA is eminently able to do (but which I personally think is a bad idea).
回答3:
Although, there are not always required, UML diagrams do help a third party to understand your code. The whole process of implementing a UML digram to code could make your debugging easier as well, as you mentioned above you will be looking at 'digram' rather than plane code.
来源：https://stackoverflow.com/questions/19520722/is-uml-class-diagram-necessary-to-design-the-ui