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Abstracting Xamarin Android SharedPreferences

The standard way to get/set SharedPreferences in Xamarin is with the following code.

Get Preference:

var shared = con.GetSharedPreferences(_preferenceName, FileCreationMode.WorldReadable);
 var value = shared.All.Where(x => x.Key == key).FirstOrDefault().Value;

Set Preference:

var shared = con.GetSharedPreferences("PreferenceName", FileCreationMode.WorldWriteable);
            var edit = shared.Edit();
            edit.PutString(key, val);
            edit.Commit();

The main issue I have/had with this is you often have to know what will be returned, and what type you need to save as. Usually this isn't difficult, but it adds an un-needed level of complexity.

The other major issues I have with this, is that it is quite verbose, and unnecessary. The code duplication here can be quite high.

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Xamarin For Android The Good: (Part 1 of 4)

Introduction

This will be a series of blog entries where I discuss the Xamarin platform for Android.

I really enjoy C# programming language (JavaScript second)....Linq, Generics, anonymous methods, and Visual Studio are just some of the reasons I like it. Xamarin is a platform that gives you the ability you to write Android applications in c#.

When I heard about Xamarin I naturally, wanted to give it a shot. Having tried Eclipse, and Android Studio for android development I was no idiot when it came to the platform. So I got a license, and did nothing with it for six months, until a few weeks ago. After only 3 days I created Ultimate Gravatar Sync. An app that sync's your contacts gravatar images to their picture in your phone.

C# with no compromise

The Xamarin platform uses mono, and some kind of voodoo bindings to the Java libraries to make it work. I wont go in depth, but the native features of the C# language are there to use. I never felt like my hands had been tied, that all of a sudden I couldn't use a library that is normally part of the GAC (Global Assembly Cache). When I needed multi-threading, System.Threading was there, and when I needed to use C# Generics I had no issues implementing them.

Xamarin execution

Manage Android Manifest files

One of the things that blew me away about the platform, was that I never had to add anything to my manifest file. For those of you whom don't know, Android requires an XML config detailing the permissions you require, and the classes you have in your application.

Simple decoration such as:

[Activity(Label = "Label", MainLauncher = true, Icon = "@drawable/Icon")]

Will Generate in your manifest file as:

<pre>
<activity
android:label="Label"
             android:name=".logoActivity" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </pre>

Adding permissions is also easy:

[assembly: UsesPermission(Android.Manifest.Permission.Internet)]

Using Java Libraries

Xamarin provides some kind of crazy visual studio project, that will essentially provide c# bindings to Java libraries you require. To bind Simply create a Java Binding project, adding the .Jar files, and then build. Watch the magic happen. They do note that you sometimes need to do some configuration for certain libraries, however I had no issues with the one I tried. On top of that if you really needed to, you could access the Java Native Interface for even more power.

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