Study Notes: Design Patterns: MVC (Part 3) Windows and Views (Part 4)

Study Notes 3: Design Patterns: MVC

P 141

·     The Model View Controller(MVC) is one of the basic design patterns around which frameworks are designed.

·     A design pattern is a commonly used template

·     MVC pattern is populated with 3 kinds of objects

o   Model Objects

§     Engine of the app, app’s data and logic

§     Like a particular t.v. program, independent of set brand and home wiring/cable/delivery method

o   View Objects

§     Displays things on the screen

§     Responds to user actions

§     Anything I see in an app is a kind of view object

§     Like a television screen, independent of program, just displays and responds to my touches on controls by sending info off to whomever it ought to go to

o   Controller Objects

§     Connects apps view objects TO it’s model objects

§     Like the circuitry that pulls the show off cable and sends it to the screen or requests a pay-per-view show

My examples:

M       A dairy

V       A home order form for milk that I fill out

C       The milk woman who looks at my order, puts the milk into her truck and delivers it to my home

M       My home furnace

V       My thermostat

C      

* Ductwork for my furnace that sends heat in

* also whatever mechanism the thermostat triggers that sends a message to the furnace to heat up some air and pump it into the ductwork

Study Notes 4: Windows and Views

·     Single window on iPad an instance of the UIWindow class, created by UIKit

·     A window is a specialized kind of window

·     I add views to the window

·     I don’t directly close or manipulate an iPad window

·     A view is an area on top of the window

·     View is main way that app interacts with users

o   Display content

o   Handle touch events

·     View Hierarchy

o   Content view(s) added as subview(s)

o   A view with a subview is a superview

o   One view 0 to N subviews, 1 superview

o   Subviews displayed on top of their superviews/parents

o   Controls: buttons, text fields, etc are (become) subviews

o   Drawing and Event Handling lowest level subview first rendered. Each subview returns control to its superview after it is rendered

o   UIKit framework handles the view hierarchy relationships

      

·     Kinds of Views (p 148) (are all of these views container views?

o   Container Views

o   Display Views

o   Text and Web views

o   Alert views and action sheets

o   Navigation views

o   (The window) Root container for all other views