Repeater or Bindable StackLayout

Intro

When designing a View (Page) we need to take into consideration that there might be a lot of content to show. Typically we should use a ListView, which by default is scrollable. However, what if you have to show more than one ListView on a single page? Nesting ScrollViews is a very bad practice that should be avoided unless natively supported. In this case it will most probably make sense to put all the content within a single ScrollView. But how? Here is where the Repeater or BindableStackLayout comes into play.

Continue reading “Repeater or Bindable StackLayout”

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Xamarin.Forms Recipe: Label with Letter Spacing

Setting a letter spacing for a Label in Android and iOS turned into an interesting research for me. I would expect that such a common task would be easily done with a help of a Renderer or an Effect. However, I was very surprised to discover that some platforms do not have a built-in support for setting letter spacing.

Continue reading “Xamarin.Forms Recipe: Label with Letter Spacing”

Immutable Models in MVVM

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Source: flickr/ Jeff Attaway

MVVM

The first M stands for Model – an implementation of the application’s domain model that includes a data model along with business and validation logic. Examples of model objects include repositories, business objects, data transfer objects (DTOs), Plain Old CLR Objects (POCOs), and generated entity and proxy objects.

definition source

Immutability

In object-oriented and functional programming, an immutable object(unchangeable object) is an object whose state cannot be modified after it is created. This is in contrast to a mutable object (changeable object), which can be modified after it is created.

definition source

Why bother?

Imagine the next simple situation, your application downloads a JSON,  deserialises it to an object and then presents the downloaded data. You would expect the downloaded data to be one-to-one to the data on the remote server, however the data can be accidentally or intentionally mutated. Continue reading “Immutable Models in MVVM”

Archiving your code

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Intro

Title of this blog post may sound very weird in 2018 while github / vsts / bitbucket are still up and running. However, it still seems to be very common to archive your solution and upload it to cloud or send it by email. Don’t ask me why, it is just still there.

The most painful and annoying mistake you can make is to include dependencies that can be easily downloaded or compiled code. Painful because it may significantly increase the size of the archive and annoying because you may have to download it for hours because of it. Continue reading “Archiving your code”

Visual Studio for Mac tips & tricks

Switching from old good VS (for Windows) to a new cool VS for Mac can be painful. Original VS was released in 1997 (according to wikipedia) while VS for Mac was released only in 2016. Yes, it is based on XamarinStudio which is built on MonoDevelop but it still has a long way to go in order to be close to it’s ancient relative.

In this article we will take a look on VS for Mac “hidden gems” that can optimize and smooth your workflow. All you have to do is to open Mac’s VS Preferences and read this article on the side.

Environment

Font

One of the very basic yet very important settings is the Font. While there is nothing bad using the default font, FiraCode could beautify your code and improve it’s readability by replacing sequences of characters by a single ligature.

The project repository on github contains detailed information on how to install it in your system. It’s also great because this font can be used almost everywhere.

Continue reading “Visual Studio for Mac tips & tricks”

The ultimate guide to Emojis 🤹‍♂️

 

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It is very common nowadays to express ourselves by using emojis. Instead of typing few words, we prefer to send one emoji that will express our feelings and emotions. Not sure that the other side will always get what we mean by sending a 🧞 , but that is another story.

In this article we will learn:

  1.  How to use emojis in static content like Labels and Buttons
  2.  How to define and use emoji in XAML only
  3.  How to define and use emoji using C#

Continue reading “The ultimate guide to Emojis 🤹‍♂️”

User input validation in Xamarin.Forms

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One of the very common tasks that any mobile developer meets is validation of the user input. It can be an email, password complexity, length, not empty or any other sort of input validation. In this article we will try to find an appropriate light-weight and reusable solution, so let’s start!

Continue reading “User input validation in Xamarin.Forms”