Start developing iOS apps today.pdf parti:introduction Knowledge points Summary

Parti:introduction Summary (This chapter mainly introduces tools for app development and a review of some object-c concepts)

(next to the following bold words for personal understanding, if not also please point out)

Objects (object) package data with related behavior;

A Class (Class) describes the behavior and properties common to any particular type of object.  

You do an object by creating an instance (object instance) of a particular class.

When you allocate (assign) an object, you set aside enough memory for the object and set all instance variables to Zer O

initialization (Initialize) sets an object ' s initial state-that are, its instance variables and properties-to reasonable V Alues and then returns the object.  

Class Inheritance (Inheritance of classes), the idea of a class inherits behaviors from a parent class

When one class inherits from another, the Child-or subclass (subclass)-inherits all the behavior and properties defined By the parent.

Objects interact by sending the other messages at runtime. In objective-c terms, the one object sends a message to another object by calling a method (calling methods) on that obj Ect.  

If you have a object Someperson of class Xyzperson, you can send it the SayHello message like this:

[Someperson SayHello]; (Personal understanding on the left is the object, the right is the calling object method)  

A protocol (protocol) defines a set of behaviors that is expected of an object in a given situation.  

Automatic Reference Counting (ARC) makes memory management straightforward by getting the compiler-keep track of who ow NS an object;

An instance of the UIApplication class, called the Application object (Applied object)

An instance of the Appdelegate class, called the app delegate (application delegate).

The app delegate creates the window where your app's content is drawn and provides a place to respond to state transitions Within the app.

As your app starts up, the application object calls predefined methods on the app delegate to give your custom code a Chan Ce to does its job

The app delegate interface contains a single: window. The delegate keeps track of the windows in which all of the your app content is drawn.

A storyboard is a visual representation of the app ' s user interface, showing screens of content and the Transitio NS between them. The flow-or Story-that drives your app is storyboards to lay out.

Start developing iOS apps today.pdf parti:introduction Knowledge points Summary