What is wrong about the combination mode?
A. It obscures the concept of simple elements and complex elements in our tree structure problem. Client programs can handle complex elements in the same way as simple elements, thus decoupling the client program from the internal structure of complex elements.
B. A one-to-many dependency relationship is defined, allowing multiple observer objects to listen to a certain topic object at the same time. This topic object will notify all observer objects when the state changes, so that they can update themselves automatically
C, branches and leaves implement a unified interface, the interface is combined inside the branch
D. Combine objects into a tree structure to represent the "part-whole" hierarchy. Combined mode allows users to use single objects and combined objects consistently
Answer:B
What is wrong about the combination mode?
A. It obscures the concept of simple elements and complex elements in our tree structure problem. Client programs can handle complex elements in the same way as simple elements, thus decoupling the client program from the internal structure of complex elements. B. A one-to-many dependency relationship is defined, allowing multiple observer objects to listen to a certain topic object at the same time. This topic object will notify all observer objects when the state changes, so that they can update themselves automatically C, branches and leaves implement a unified interface, the interface is combined inside the branch D. Combine objects into a tree structure to represent the "part-whole" hierarchy. Combined mode allows users to use single objects and combined objects consistently