From the course: Programming Foundations: Design Patterns

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Solution: The Observer pattern

Solution: The Observer pattern

From the course: Programming Foundations: Design Patterns

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Solution: The Observer pattern

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(energetic music) - [Instructor] Here's our solution to the challenge. We created a new subject interface that the weather station implements, and we added a list of observers to the weather station. We created implementations of the methods required by the subject interface to allow observers to come and go and to notify observers when the weather station's data changes. We also added a new observer interface with an update method and had each of the classes interested in the weather data implement that interface. That means each class needs to implement the update method. In addition, each class gets a reference to the weather station to access the methods in the weather station to add and remove themselves whenever they want from the list of observers.

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