Jens Hagfeldt

Jens Hagfeldt

Upplands-Väsby, Sweden

My name is Jens Hagfeldt, I'm an Developer (iOS and Web) with a background of 23+ years, working as a preschool-teacher. It is with great anticipation I now look forward on working as a Developer for at least as many years.

16,548

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Skills & Experience

  • Job Title

    Developer (iOS & Web)

  • Spoken Languages

    • Swedish, English
    • English
  • Looking for work

    Yes

219 Achievements

  • Introduction to Video Games
  • Adding Sound Effects
  • Personalizing The Story
  • Refactoring Our Code
  • Creating the User Interface Programmatically
  • Creating a Story
  • Navigating Through An Adventure
  • Introduction to Unit Testing
  • Introduction to Collections
  • Swift Operators
  • Swift Types
  • An Introduction to Swift Programming
  • Adding Metadata to Photos
  • Adding Image Filters
  • Taking a Selfie
  • Introduction to CollectionViews
  • Deleting and Updating Data
  • Fetching Data Using Fetch Requests
  • Inserting and Saving Data Using a Context
  • Understanding the Core Data Stack
  • Paged Scrolling
  • Understanding Scroll Views
  • Media Basics
  • Structuring Tables
  • Implementing Maps and Search
  • Obtaining a Location Fix
  • Displaying Data in Table Views
  • Enhancing the Networking Stack
  • URLs and Parameter Encoding
  • Introduction to UITableView
  • Implementing a Forecast Client
  • Protocol Oriented Networking
  • Fetching Data From the Web
  • Modeling Forecast Data
  • Asynchronous Error Handling
  • Closures in Cocoa Touch
  • Building Standard Library Functions
  • Closure Expressions
  • First Class Functions
  • Visual Format Language
  • Auto Layout in Code
  • Trait Collections
  • Inequalities, Content and Priorities
  • The Constraint Equation
  • A History Lesson
  • Generics with Swift 2 - Beyond Basics
  • Generics with Swift 2
  • Singletons
  • Adding Sound Effects
  • Refactoring the Model
  • Creating the User Interface Programmatically
  • Creating a Story
  • Navigating Through an Adventure
  • Memory Management in Swift 2
  • Extensions and Protocols
  • Value Semantics, Type Methods and Inheritance
  • Object Initialization in Swift 2
  • Properties in Swift 2
  • Displaying Additional Views
  • Using the Vending Machine
  • Loading Data From a Resource
  • Modeling An Interface
  • Two-stage Object Creation
  • What Are Design Patterns?
  • Error Handling in Swift 2.0
  • Creating Flexible Objects Using Protocols
  • Swift 2.0 Protocols
  • Objects and Optionals
  • Introduction to Optionals
  • Introduction to Enumerations
  • Prepare and Plan
  • Running Apps on a Device
  • Improving Our User Interface
  • Structs as Data Models
  • View Controllers and Views
  • Getting Started with iOS Development
  • Differentiating Between Objects
  • Class Inheritance
  • Classes
  • Complex Data Structures
  • Function Parameters
  • Functions in Swift 2.0
  • Control Flow with Conditional Statements
  • Control Flow With Loops
  • Swift Dictionaries
  • Introduction to Collections
  • Implementing the Detail View
  • Swift Operators
  • Swift Types
  • An Introduction to Swift Programming
  • Introduction to Video Games
  • Delegation in iOS
  • Introduction to Delegates
  • Color Theory
  • Principles
  • Elements
  • Custom Table View Cells
  • Next Week's Weather
  • Upgrading Stormy
  • Introduction to Table Views
  • Creating Flexible Objects with Protocols
  • Protocols
  • What is Agile?
  • Refreshing the Data
  • Adding Weather Icons
  • Managing Complexity
  • Interacting With Data From the Web
  • Simple Data Structures
  • Closures in iOS
  • Closures and Closure Expressions
  • Functions as First Class Citizens
  • Pointers and Memory
  • Functional Programming in C
  • Cocoapods
  • The Local Development Environment
  • Getting Started with Android Studio
  • Finishing the User Interface
  • The Model-View-Controller Pattern
  • Fundamentals of C
  • Intents and Multiple Activities
  • User Input
  • Swift Value vs Reference Types
  • Swift Properties
  • Responsive Patterns
  • Media Queries
  • Responsive Theory
  • Publishing on Google Play
  • Testing and Debugging
  • Ruby Numbers (Ruby Basics)
  • Ruby Strings (Ruby Basics)
  • How Ruby Works
  • Improving Our Code
  • Coding the Fun Facts
  • Basic Android Programming
  • Self-Assessment
  • Getting Started with CSS
  • Table Basics
  • Refactoring Our Code (Swift)
  • Building the Master and Detail Views (Swift)
  • Building a Music Library and Playlists (Swift)
  • Using a Navigation Controller With Segues (Swift)
  • Working With Multiple View Controllers (Swift)
  • Swift Inheritance
  • Swift Classes and Objects
  • AngularJS MVC Frameworks
  • Building a Command Line Application
  • Introduction to Node.js
  • Choosing Options
  • Organizing Forms
  • Form Basics
  • Creating the Initial Screen Layout
  • Getting Started with Android
  • Downloading Data with NSURLSession
  • Collection Views
  • WordPress Themes
  • Installing Wordpress
  • Swift Structs and their Methods
  • Swift Enums and their Methods
  • Swift Enums
  • Swift Structs
  • An Overview of WordPress Frameworks
  • Working with CSS and JS in WordPress Themes
  • Starting a WordPress Theme
  • Displaying Our Weather Data
  • Data Modeling With Structures
  • Concurrency
  • Pulling Data From the Web
  • Deploying to a Device
  • Debugging Our App
  • Improving Our User Interface
  • Using a Data Model
  • Views and View Controllers
  • Getting Started with Xcode
  • Swift Optionals
  • Swift Parameters and Tuples
  • Swift Functions
  • Control Flow
  • Collections
  • Operators
  • Types
  • Variables and Constants
  • Retrieving and Viewing Data from Parse.com
  • Capturing Photo and Video Using UIImagePickerController
  • Relating Users in Parse.com
  • Using Parse.com as a Backend and Adding Users
  • Designing and Starting the App
  • Particle Systems and Keeping Score
  • Artificial Intelligence and Sound
  • Physics and Collision
  • Actions and Animations
  • Game Loop and Texture Atlas
  • Intro to Sprite Kit
  • Introduction to Game Design
  • Create Bootstrap Styled Theme Templates
  • Setup a Bootstrap Theme
  • Local WordPress Development
  • Custom Detail View Controller
  • Custom UITableViewCell
  • Deleting Data
  • Listing Data using NSFetchedResultsController
  • Inserting and Saving Data
  • Understanding Core Data
  • Moving Forward with UX
  • Tools UXers Use
  • How UXers Think
  • What Do User Experience Designers Do?
  • What is User Experience (UX)?
  • Introduction
  • Debugging HTML and CSS Problems
  • Sharing a Website
  • Responsive Web Design and Testing
  • Adding Pages to a Website
  • Styling Web Pages and Navigation
  • Customizing Colors and Fonts
  • CSS: Cascading Style Sheets
  • Creating HTML Content
  • HTML First
  • Beginning HTML and CSS
  • Newbie