1. Explain quick enumeration.
Fast enumeration is an IOS programming language feature that allows you to enumerate the contents of a collection. It will also enable your code to execute your code faster because the internal implementation reduces message sending overhead and increases pipelining potential.
2. Explain ARC.
The arc indicates the automatic reference count. It is a compilers – level feature that simplifies the object lifecycle management process. ARC evaluates the life cycle requirements of the object and automatically includes the appropriate methods that need to be called during compilation.
3. Explain mutable and immutable types in target C language.
Mutable types mean that you can change things as needed. However, when an object is marked immutable, it means that the data cannot be modified after initialization. Therefore, the value stored here is constant.
Example: The NSString and NSArray values cannot be changed after initialization.
4. What is garbage collection?
Garbage collection is a memory management feature. It manages the allocation and release of memory to your application. When the garbage collector performs a collection, it checks for objects in the managed heap that are not being executed by the application.
5. Explain XIB.
Xib is the file extension associated with the InterfaceBuilder file. It is a graphical software for testing, developing and designing user interfaces for different software products. This extension file also contains development time format files, which include interface files created with interface builder software.
6. What programming languages are used for IOS development?
The language used to develop oIOS is as follows: 1. Objective-c 2.. net 3.C 4.HTML 5 5.JavaScript 6.SWIFT
7. Explain the application ID.
It is primarily used to identify one or more applications from a unique development team. It consists of a string divided into two parts. The string includes a team ID and a delimited bind ID search string. Team ids are assigned by Apple and are different for each development team. AppDeveloper provides a binding ID search string.
8. Explain the use of the structure.
Struct is a DataType in the C programming language that allows other data to be encapsulated into a single cohesive unit. It is similar to objects, but in the C programming language.
What is an object?
Objects are essentially variables of class type. Objects are basic runtime entities in object-oriented systems. They may represent a place, a bank account or a person.
10. Use concurrency in IOS.
Here’s how to implement concurrency in IOS: 1. Thread 2. Scheduling queue 3. Operation queue
As an iOS developer, you may need to check out this iOS resource.
11. But but what?
Coco is an application development environment for MacOSX and IOS. It includes compilation of runtime systems, object-oriented software libraries, and integrated development environments.
12. What is a framework?
It is basically a conceptual structure or an intensional scheme that supports the extension of the structure into something useful. A Framework is a layered structure that indicates what programs can or should be built and how they will interact. The framework includes actual programs that mention programming interfaces and programming tools for using the framework.
13. Explain the keywords alloc and New.
The Alloc keyword is used to create a new memory location in the system. However, it does not initialize it. For the New keyword, it also helps to create a New memory location in the system. However, it may not initialize the content as the alloc keyword does.
14. What is the selector in target C?
A selector in target C can be used to reference the name of a method to an object when it is used in source code messages. It also references a unique identifier that can be replaced with a name when compiling source code. All methods with the same name have the same selector.
15. Soliciting frames for cocoa.
The framework developed for Cocoa is as follows: 1. Foundation 2. Application Toolkit
16. What is a bundled ID card?
The binding ID uniquely defines each IOS application. It’s specified in Xcode. It is a search string provided by ApplicationDeveloper to match the binding ID of a single application or a group of applications.
What is a class?
An entire dataset of objects can use classes to generate user-defined data types. Objects are basically variables of class type. Once a class is defined, multiple objects of its type can be created. A class is a collection of objects of similar types.
18. Explain the difference between inheritance and category.
Classes allow only methods to be added. It does not allow data members to be included, unlike inheritance, which can add data and methods at the same time. A category includes the full application in its scope, while the scope of inheritance is only in that particular file.
19. Explain the AppBundle.
During IOS application development, Xcode packages it as a package. A Bundle is a directory of files that groups related resources together in one place. It contains application executables and supports resource files such as localized content, image files, and application ICONS.
20. What is Swift?
SWIFT is a programming language for developing applications for OSX, IOS, WatOS, and tvOS. These applications are developed using C and object-C. It doesn’t have the constraints of C programming. It has features that are easier to develop and provides more flexibility.
21. What is a protocol in object-C programming language?
The protocol is used to define the list of required optional methods that the class needs to implement. If the class adopts a protocol, all the required methods must be implemented in the adopted protocol. It is the same interface as in Java and pure virtual classes in C++. Cocoa uses protocols to support interprocess communication through target C messages.
22. Explain formal agreements.
Formal protocols allow you to define interfaces for a set of methods without any implementation. It is useful for DistributedObjects because they allow protocols to be defined for communication between objects.
23. What is polymorphism?
It enables a method to behave differently in different situations. The task of creating a function or an operator in different instances is called operator overloading and is an implementation of polymorphism.
24. Distinguish between release and pool drainage.
The free keyword is used to free unused memory locations in the system. The LEAL keyword is used to release NSAutoRelasePool.
25. What is a collection?
Collections are the basic framework classes used to manage and store groups of objects. The main purpose of collections is to store objects as collections, dictionaries, or arrays.
26. Explain the meaning of automatic release.
Auto release: When you send an object auto release message, it is added to the local auto release pool. When the auto release pool is destroyed, the object will receive a publish message. If the object’s RetainCount is Zero, the garbage collection destroys the object.
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27. What is the first transponder and transponder chain?
A response chain is a hierarchy of objects that can respond to received events. The first object in the ResponderChain is called the first responder.
28. Explain Web services?
Web services are application components that allow communication using open protocols. These Web services are self-describing and self-containing. Web services can be found using UDDI. The foundation for developing Web services capabilities is extensible Markup Language (XML).
29. Explain the difference between cocoa and cocoa touch?
Cocoa is an application framework for developing applications in the MacOSX environment. It’s basically a combination of two frameworks, the AppKitFramework and the FoundationFramework. CoocoTouch is the application framework for the iPodTouch. The IPhone and the tablet. It includes the Foundation framework and UIKit framework.
30. Explain the folds.
Plist represents an attribute list. It is a key-value store for applications that hold and retrieve persistent data values. This is specifically for iPhone development. It’s basically an XML file.
31. Explain IPA.
IPA stands for iOS App Store package. It has an.ipa extension, which stands for the iPhone app archive file that stores iPhone apps. Each file is compressed using ARM architecture binaries and can only be installed on an iPhone, iPad or iPodTouch. Much of it is encrypted using Apple’s FairPlay DRM technology.
32. Which JSON framework does IOS support?
SBJSON is a framework supported by IOS. It is a generator and a JSON parser for target C. SBJSON provides a flexible API and makes JSON processing easier.
33. Explain your legacy.
Inheritance is an object-oriented programming concept. It allows you to develop a new reusable class and extend the behavior defined in another class.
34. How can I improve battery life during application execution?
The application is notified whenever the operating system transfers an application between the background and the foreground. It helps prolong battery life by identifying the exact functionality in the background, which also contributes to a better user experience in foreground applications.
35. Does IOS support multitasking?
Multitasking is supported in IOS version 4 and later. Multitasking is a feature that keeps an application in the background until it is restarted or terminated.
36. What is Xcode?
Xcode is a collection of software development tools apple has developed for developing applications. It is an integrated development environment (IDE). It is primarily used to develop IOS and OSX applications.
37. Explain layer objects.
Layer objects are data objects that represent visual content. They are used to render content. Layer objects can be customized, and these custom layer objects are used to implement complex animations and other types of complex visual effects.
38. What framework is used to build the iOS user interface for applications?
UIKit framework is the framework used to develop the user interface for IOS applications. The UIKit framework provides views, Drawing models, controls, event handling, Windows designed specifically for touch screen interfaces.
39. Explain the interface.
Interfaces allow a feature to be defined as a group of properties, methods, and events associated with it. It defines the events, properties, and methods that a class can implement.
40. Add a cocoa touch frame.
The framework for Cocoa Touch is as follows: 1. Foundation 2.UIKit
41. How to declare variables in SWIFT?
Variable num = 42
42. What is the maximum byte size for push notifications to AppleServer?
The maximum memory size for sending push notifications to AppleServer is 256 bytes.