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Issue 17.1 ('iOS Success')
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Building a Data-List Controller

Designing and implementing a controller for the data-list domain

Issue: 17.1 (January/February 2019)
Author: JC Cruz
Author Bio: JC is a freelance writer based in British Columbia. He is a regular contributor to MacTech Magazine and Dr Dobb's Journal. Away from the writing pile, JC spends quality time with his nephew, as a proper uncle should.
Article Description: No description available.
Article Length (in bytes): 42,132
Starting Page Number: 53
Article Number: 17106
Related Link(s): None

Excerpt of article text...

Last time I showed how I designed and implemented a controller to handle the data-entry domain. Now, I shall do the same for the data-list domain.

First, I will explain what makes these two problem domains different. Then I shall introduce the new controller class and describe its design. I shall show how I implement the data-list controller, how to make it work with its data-entry kin and how to update the window views. And I shall evaluate the controller with the usual software metrics.

The revised version of the FooHealth demo project (Mk2.1) is available from the magazine's website. Readers must have a working knowledge of Xojo and object-oriented design.

The Problem Domains

Many of the controller modules in the FooHealth project have at least two problem domains (Figure 1). There is the data-entry domain, where the module conveys data from model to entry window view. The module interacts with user-patients and sends new or updated data to the model for storage. It also prompts for new data with a blank entry view.

The data-list domain

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