Virtual Life App with Inheritance

• Languages: Javascript ES5
• Languages Additional: Javascript ES6 Modules
• Tools: VS Code, Live Server extension, Git (if available)
• Libraries: animate-world.js
• Patterns and Practices: Separation of concerns, Factory method pattern, Inheritance

Feature Specification

 

• Same features as Virtual Life ES6 Modules project

 

Code Design

 

• Use object inheritance with a parent object named world item and inherited objects for plant and animal world items
• Create a world item prototyped object

 

• Add the following methods.
• act() - will be overridden in the inherited objects

 

• This object should contain any of the general data for all world item type objects i.e. location data.

 

• This object should have any general methods that might be used by inherited objects.

 

• Create a plant world item prototyped object that inherits from world item.

 

• Override the act method

 

• Create an animal world item prototyped object that inherits from world item.

 

• Override the act method

 

• Change the world item factory to build the correct type of world item object for plants and animals.

 

Notes

 

·         How to inherit from an object

 

ES5 methodology:

 

o    Invoke the parent object's constructor in the inherited object's constructor:

               function LivingWorldItem(...args) {

                       WorldItem.call(this, ...args);

               }

o    Set the inherited object's prototype to a copy of the parent's prototype:

 

   LivingWorldItem.prototype = Object.create(WorldItem.prototype);

ES6+ methodology:

 

o    Use the class keyword to create a new object class, and extend the parent class, passing along any constructor arguments to the superclass:

               class LivingWorldItem extends WorldItem {

                       constructor(...args) {

                               super(...args);

                       }

               }

References

• Inheritance in JavaScript