Bluetooth Smart Beacon Specifications

Apple released iBeacon with iOS 7. iOS is a very big segment of smart phone users but there is a big market for android and other OSes as well. As apple made it difficult for the iBeacon manufacturers for providing SDKs for Android, they came up with alternate specifications as a workaround. One such example is AltBeacon from Radius Network. You might...

iBeacons & Bluetooth LE

Bluetooth Low Energy (Bluetooth LE) is also known as Bluetooth Smart. It is designed to provide Bluetooth based functionality without draining the battery power of your device. Bluetooth LE is part of Bluetooth 4.0 specification. You can download the specification from Bluetooth.org. You would find three kinds of…

Android Development - Services

This is a continuation of a post for building an android app for displaying GitHub contributions of a user. We are pulling down profile and repository details of the user. As we are adding features to the app, we have been learning about android and its development model.

Currently we are at the point that we can download the data asynchronously and display it on the UI. We can also change user and the data is downloaded for the new user. In this post, we want to build up on this by moving all the heavy lifting for downloading the data to a background service...

Android Development - Offline Support

This post is amongst the series of post for discussion about development of an App in Android Platform. We have been developing an app, named GitHub Contributions as an example. In each post, we keep adding some new feature to the app, which adds to our knowledge about android.

In this post, we are going to see how we can add offline support to our app. So if a user has launched our app and there is no internet connection available, we cannot download user profile’s data from github.com. In this case, we can show any previous data downloaded for the specified user. If we are running the app for the first time for the user, then we can just show a Not-Connected message on the screen. As soon as the user connects to the network, we can attempt to download the information and show the pretty view.

Read more....

Android Development - Scheduled Execution

This is a continuation of our post discussing different areas of android development. We are getting introduced to android development while developing an application GitHub Contributions App. There are a number of ways we can delay processing of some work in android. It also allows us to execute these work items on a periodic basis. There are a number of options for an android developer for introducing scheduled execution.

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GitHub Contributions App - Android Internal file Storage

This is a continuation of a post for building an android app for displaying GitHub contributions of a user. We are using name of user for pulling down profile and repository details of the user. As we are adding features to the app, we have been learning about android and its development model.

Currently we are at the point that we can download the data asynchronously and display it on the UI. User can also change user and the data is downloaded for the new user. In this post, we want to build up on this by adding the following:

Keep the data in a file so that when the app needs it it can just be pulled from a file rather than being downloaded from the web. This can also cater to the offline scenarios when the app is launched while being disconnected from the network. We also don’t need to download data if the app is launched within 3 hours of when the data was downloaded last time.

Read more...

GitHub Contributions App - Android App Preferences

In this post we are continuing with the app. We will be updating the action bar from default to custom. Currently, you can only see author’s GitHub contributions. We will be providing a setting to change GitHub user. The feature will be provided by adding an action bar button for settings. Read more...

Adding PCL Reference to Mono Touch and Mono for Android Applications

October has been a fun month. I got to travel across the country to three different places, met with amazing people and shared the common enthusiasm about technology. It's like our souls know each others. Code camps are opportunities for learning for everyone; including presenters and attendees. For one, presenters in one session like to go to other sessions as attendees, the other is, when they are asked thought provoking questions covered with practical problems of the individual developers. Most of the times, it makes the presenter think about the specialized area; it makes them see it in a different perspective.

I am planning a separate post about the experiences about the October. I think this would be a good idea to discuss some questions on the blog. Let's discuss first question in this post. The question is:

Can we add PCL references in Montouch and Mono for Android applications?

The short answer is Yes; and we can also do that in Visual Studio. I have Xamarin Starter edition installed on my machine. It also includes a trial version of Visual Studio extension for Xamarin tools.

Xamarin Studio
Here I have a sample solution called NameReflectorApp. It has a portable class library project Xamarin.Core. It also has an android application project NameReflectorApp.Android.



The portable class library project is targeting a number of frameworks as shown below:



This is targeting Profile 158 of .net portable subset. There are still some issues with Xamarin Studio like you see a warning message at the bottom of the target frameworks. But don't worry, this should still work. We cannot see here Mono for Android as one of the target frameworks but we can still add such references. In Xamarin's term, this is called Edit References, funny...



Visual Studio Support
Xamarin has support for Visual Studio. But this is not available for all the editions. Generally speaking, it is available for more expensive ones. But we can still play with the extension during the trial period available when we install the starter edition. The best thing is we can decide when we want to start the trial period. We can use this option to first familiarize ourselves with the technology and when we need to see how well it integrates with our current Microsoft technologies, we can start the trial period.



Visual Studio is not as forgiving in adding references in such case. There are issues with the Xamarin's Visual Studio extension. As we add our portable class library's reference to Android application, it shows up the following error dialog.



Xamarin developer community terms this situation as a lie. In order to fix this, we need to use some xml hack. I would totally recommend the following post where we discussed how we can add additional frameworks options for Portable Class Library projects.



As we discussed in the above post, we can add options for additional target frameworks by adding files the Supported Frameworks folder for a target profile. Let's add two new Xml files to our selected profile as follows:



The contents of these files are as follows:

After adding the above files, we need to restart Visual Studio. After that, as we go to the PCL's property page, we see that there are already Xamarin.iOS and Xamarin.Android in the target framework list. If we hit Change button, we see additional options for Xamrin.iOS and Xamarin.Android. These options are checked.



Adding the reference to the Android application project goes through just fine. Here is the portable library's reference added to the project's references list.



If you have Xamarin Studio running then restart this and open the same solution again. You can see that these new frameworks are also available in Xamarin, which is amazing.



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