Junior IOS Developer Interview Questions and Answers

MVC focuses on separating data, presentation, and logic, while MVVM adds a ViewModel layer to handle data binding.

• MVC stands for Model-View-Controller, where the model represents the data, the view represents the UI, and the controller acts as an intermediary between the two.

• MVVM stands for Model-View-ViewModel, where the ViewModel layer is added to handle data binding between the view and the model.

• In MVC, the controller directly communicates with the model and updates the v...read more

Guard statement is used to early exit from a function if a condition is not met.

• Used to check for conditions and exit early if not met

• Helps in reducing nesting levels in code

• Improves code readability and maintainability

• Example: guard let value = optionalValue else { return }

Classes and structures are both used to create custom data types in object-oriented programming, but they have some key differences.

• Classes are reference types, while structures are value types.

• Classes support inheritance and polymorphism, while structures do not.

• Classes have a default initializer, while structures do not.

• Classes can have deinitializers, while structures cannot.

• Classes can be passed around as references, while structures are always copied when they are passed...read more

To find middle node of a linked list, use two pointers - slow and fast.

• Initialize slow and fast pointers to the head of the linked list

• Move slow pointer one step at a time and fast pointer two steps at a time

• When fast pointer reaches the end of the list, slow pointer will be at the middle node

A service class is a class that contains the business logic of an application and is responsible for interacting with data sources.

• Service classes are used to separate the business logic from the presentation layer in an application.

• They often interact with data sources such as databases, APIs, or other services.

• Service classes can contain methods for performing operations like fetching data, processing data, and updating data.

• They help in keeping the codebase organized and m...read more

ViewController life cycle refers to the sequence of events that occur during the creation, loading, and unloading of a view controller.

• viewDidLoad() is called when the view controller's content view is created and loaded into memory.

• viewWillAppear(_:) is called just before the view controller's content view is added to the app's view hierarchy.

• viewDidAppear(_:) is called after the view controller's content view has been added to the app's view hierarchy.

• viewWillDisappear(_:) ...read more

Tableview delegate methods are used to customize the behavior and appearance of tableviews in iOS applications.

• Implementing UITableViewDataSource methods like numberOfRowsInSection, cellForRowAt, and heightForRowAt to populate the tableview with data.

• Using UITableViewDelegate methods like didSelectRowAt, heightForHeaderInSection, and heightForFooterInSection to handle user interactions and customize section headers and footers.

• Utilizing methods like willDisplayCell to perform...read more