Decoupling dependency creation from usage
The practice of decoupling dependencies is not specific to Flutter. There is a high chance that you have already encountered the concept of IoC, as well as specific patterns such as DI and SL. If you have, this chapter will highlight some Flutter-specific approaches, along with their pros and cons. If you haven’t, that’s not a problem. We will discuss them in detail now. However, before we delve into the terminology and provide a solution, we need to identify the problem. Let’s revisit CartModel, which we created in Chapter 4. In Chapter 6, we refactored CartModel to adhere to the repository pattern by renaming it to InMemoryCartRepository and implementing the abstract CartRepository. Besides doing this, we have also removed the static constructor. Now, let’s zoom in to understand why we did that.
Identifying the singleton pattern
The previous instantiation of CartModel used a very specific approach and looked...
