Top Xamarin Interview Questions and Answers (2024)

Xamarin is an open-source, cross-platform framework developed by Microsoft. Built on the .NET framework, Xamarin is used to create native mobile iOS, Android, and Windows applications. 

The need for mobile application development has skyrocketed over the past decade and is not slowing down anytime soon. This, in turn, also calls for skilled developers who can develop native and cross-platform applications. 

The following Xamarin interview questions and answers will help you learn more about the framework and prepare for your Xamarin interview. 

1. What are the advantages of Xamarin?

• Open-source: Xamarin is open-source, and its core libraries are available on GitHub. However, some of the tools used to develop may be proprietary to Microsoft and not available as open-source. 

• It is cost-effective as the framework uses a single technology stack (C# and . NET) and reusable code. This also makes maintenance and updates easier.

• Fast development process due to shared codebase and the ability to maintain one set of codes that works across multiple platforms. 

• Code-sharing across multiple platforms: Most of the code of an app built using Xamarin can be shared across multiple platforms. This allows the developers to write most of the code once and deploy it on Android, iOS, and Windows,  

• Consistent UI across devices using Xamarin.Forms and without using much native code.

• Incredible support and well-documented to help in the development process.

2. What are the disadvantages of Xamarin Development?

• The development of UI in Xamarin is time-consuming

• Apps created in Xamarin are between 3 MB to 15MB filesize in store (Large Filesize)

• The developer needs to create a linkage in the OS, which is difficult for the user

3. What is the Xamarin profiler?

Xamarin profiler is a tool developed by Microsoft that helps developers analyze the app’s behaviour and understand its memory allocation and other performance-related aspects. This helps identify performance and memory-related issues and further optimize the app.

4. What is Xamarin Forms?

Xamarin.Forms is a UI framework based on Xamarin. It allows developers to build user interfaces in a single shared codebase. Xamarin.Forms eliminate the need to create native UI codes for separate platforms and allow developers to create a single UI codebase written in XAML (or C#). This code can then be rendered across different platforms.

5. What are the different types of layout control in Xamarin Forms?

Below are some of the basic layouts in Xamarin:

1. StackLayout positions its child element in a stack, which can be vertical or horizontal

2. Grid arranges the child elements in rows and columns

3. AbsoluteLayout positions the child element according to the position of the parent element

4. Relative layout positions a child element relative to itself or any other child element

5. ScrollView adds scrolling to your page

6. The frame is used to show a rectangle around the child

7. ContentView acts as a container for a single child view

8. FlexLayout arranges the child elements similarly to that of CSS Flexbox

9. CollectionView is used to display a collection of data items

10. ListView shows the elements in a stack

11. TableView organizes the data in a table format

6. What are the different types of pages in Xamarin Forms?

The following are the common types of pages in Xamarin.Forms:

1. ContentPage: A simple blank page that holds content

2. MasterDetailPage: A page consisting of a Menu that contains a list of pages and Details that show the currently selected state. MasterDetailPage has been replaced by FlyoutPage in the newer Xamarin.Forms versions.

3. NavigationPage: It manages the navigation between the pages

4. TabbedPage: Contains multiple tabs and enables navigation between the tabbed pages

5. TemplatePage: It is the base class for the ContentPage

6. CarouselPage: It provides navigation between pages with a right or left swipe

7. FlyoutPage: Manages a flyout menu and a detail area mainly used for navigation and layout flexibility

7. Explain Xamarin Android.

Xamarin Android is part of the Xamarin framework that allows the creation of Android apps with C# and .NET instead of Java or Kotlin. Xamarin.Android provides integrations with Android API, allowing developers to interact with Android features and services

8. What is data binding in Xamarin?

Data binding in Xamarin synchronizes the user interface with its underlying data layer. It ensures that the UI is always in sync with the data and minimizes the need for manual updates every time the data changes.  

9. What is a custom renderer in Xamarin forms?

Components (controls) in Xamarin forms can be rendered differently on different platforms using a renderer class. This renderer class maps an Xamarin Forms control to a native control on each platform. By creating a custom renderer, you can customize the behaviour and appearance of control to align with the look and feel of each platform. 

10. What is Fresh MVVM?

MVVM stands for Model-View-ViewModel framework. An MVVM is a software design pattern that separates an application's UI (View) from its underlying business logic and data (Model) through an intermediary (view model). Fresh MVVM is a lightweight and flexible MVVM model specifically designed for Xamarin. 

11. How do you create navigation from one page to another?

Navigation can be navigation between pages in Xamarin.PushAsync() and Navigation.PopAsync() methods.

Navigation.PushAsync() method is used when navigating from one page to another. 

Navigation.PopAsync() method is used to move back to the previous page from the current page.

12. Explain Xamarin.Forms.

Xamarin.Forms is a cross-platform UI toolkit for writing a shared codebase for IOS, Android, and Windows Phones.

13. What are ten of the best companies using Xamarin?

• Rumble

• FreshDirect

• Rivertown

• UPS

• Zappiti

• Crowdkeep

• BBVA

• Outback

• Olo

• Alaska Airlines

14. What are the programming Languages that support Xamarin?

Xamarin supports the following Languages in the development of Mobile Applications:

•    F#

•    C#

•    Visual Basic.Net