DPS923 notes – Thu Mar 20

What is an ‘equipment’ class and object?

In Monday’s class (lab) session, you had some very good questions for your professor. This question arose a few times, and after some thought, web have an answer.

What is an ‘equipment’ class? What is an ‘equipment’ object?

Well, it is an equipment description.

It is NOT modelling a physical piece of equipment. It is NOT modelling a real-world thing.

To compare, a Player class defines the properties of a player. An instance – i.e. a Player object – models a real-world thing.

This question arose because some of us were having trouble imagining the one-to-many relationship a “helmet” had with a collection of “players”. It became obvious that one helmet object was NOT shared by a collection of players. Instead, a description of a helmet IS shared by a collection of players.

The app is not an inventory-keeping app. In other words, it will not tell us that a team has 75 sticks. Instead, it will tell us that a team may have a dozen stick descriptions.

Hope this helps.

New feature – web service request object

Your professor has created a class to hold the code needed to make requests of a web service.

The end result is that you can create custom getter methods for declared properties in your Model class, and write only one or two lines of code to make a typical “GET” request from a web service.

It’s available in ClassesV4 and later templates.

(planned) Working with the web service

A web service for the programming assignment has been created.

Features/characteristics

Making requests…

get-all
get-some-filtered
get-one
add-new
update-existing
delete-existing

Programming assignment discussion

On-device store is authoritative for Player objects.

Web service is authoritative for Equipment objects.

Topics

Summary of JSON to-and-from NSDictionary and NSArray

Predicate format strings (assigned topic?)

Shout out – Introduction to Coding Guidelines for Cocoa – HTML – PDF

(more to come)

Peter McIntyre