Monthly Archives

July 2014

Picking your Challenges – Luminance for Points

By | .NET, Blogs, C#, Fun, Windows | No Comments

One of the things I’m learning as I’m settling into my #2520orBust challenge, is picking which challenges I’m going to tackle on You have to consider the requirements of the challenge and the due dates. You also have to consider the amount of free time you have to devote to the challenge. For me, that’s not much time. So, I’m looking at the low hanging fruit right now. The next challenge on my list is the “New App Special“. It’s 250 pts, and I’ve got until the end of August. The app I have in mind is a lux…

Read More

Kendo Undocumented: Using data bindings in grid column templates

By | News | 3 Comments

I’ve found that the more I use Kendo, the more of a MVVM junkie I become. I use data binding for everything I possibly can and it has led to nothing but happiness. Then one day, I wrote a grid column with a data binding in it, and the binding didn’t work. It was weird because I was sure I had already used data bindings in other templates, and not just edit templates either. With just a little experimentation, I discovered a neat little fact: you can use data binding in column templates if the grid is initialized with data attributes….

Read More

Learning Xamarin: MVVM Light and Xamarin Forms

By | News, Xamarin | 4 Comments

Today I’m going to kick off a series of postings on creating an application using Xamarin Forms and the MVVM Light Toolkit. This is part of a larger series on Learning Xamarin… In my previous article I attempted to explain why MVVM is inherently desirable and especially so with Xamarin Forms which supports both XAML and DataBinding. In this article I will create a dead simple example (actually, I’ll steal Lauren’t simple example) to get my feet wet.

Read More

Creating a Custom Kendo UI Validator

By | JavaScript, Kendo UI, News | One Comment

Kendo UI makes it very easy to do validation with any of their built-in validators. These are built on top of the validation features in HTML5, but have been made to also works in non-HTML5 compliant browsers. The built-in validators work for 80% or more of situations, but occasionally you need to validate something in a unique way that requires some custom logic. Like much of the Kendo UI framework, Kendo UI’s validation widgets make it easy for you to customize them. For validation, the key is to create a custom validation rule when you’re setting up your validator widget, like this:


Read More

HTTP GET array param to ASP.NET MVC with Kendo DataSource

By | .NET, ASP.NET, JavaScript, Kendo UI, MVC | No Comments

This post is inspired by a recent conversation with one of my colleagues here. He had the following requirements: ASP.NET MVC controller (not Web API) Kendo DataSource reading with HTTP GET Controller action accepts a list of values So, something like this:

This is an awkward little corner case. Change any one of the requirements and everything will work just fine. Fresh out of the box, Web API understands sending multiple values in the query string (at least, with the right controller action method signature). MVC controllers understand arrays if they’re posted in the body of the request,…

Read More

Liberate your files from SQL varbinary

By | Microsoft, Tools | 8 Comments

While there are other ways of storing data files for an application, using the SQL Server varbinary data type is a straightforward way to persist your files as BLOBs (binary large objects) along with the rest of your application data.  Reading and writing that data from your application is straightforward since you typically store the data as a byte array. But here is a challenge you may run across: what if you want an easy way to export that varbinary data as the original file?  Sure, you could write a simple utility application to read the content and save it as…

Read More

Kendo UI Grid Custom Columns: Data-Dependent Command Buttons

By | JavaScript, Kendo UI | One Comment

Here’s yet another custom column example for you Kendo UI Grid users.  Last time we looked at displaying an array property as a list of links, but this time we are taking a look at using data properties to conditionally enable certain command actions on a row.  This is different from using the built-in command columns, but it give us a high level of flexibility for enabling actions on a data row.   Once again, the magic happens through a very straightforward column template that uses  properties of the row data item to determine if the command buttons should be…

Read More

Unreasonable Expectations

By | Sitefinity | One Comment

It’s extremely common to hire a custom development company to help build your project. Over the last 7 years, Falafel has worked on and delivered over 380 projects based on the Telerik Sitefinity CMS alone. In that time, I’ve learned a few things that can be beneficial for both the clients and the company. While the vast majority of projects go perfectly well, not all do. Here are a few things you can do both as a customer, and as the consulting group, to save those projects before they take a wrong turn.

Read More

Learning Xamarin: Xamarin Forms & MVVM

By | MVVM, Xamarin | 4 Comments

Xamarin Forms bring data binding, and with it a terrific opportunity to add MVVM to Xamarin applications. MVVM, however, may not be familiar to many iOS and Android developers, and I’ve therefore decided to republish and update my article MVVM: It’s Not Kool-Aid from 2010. This article is now part of my series on learning Xamarin.

Read More

Dealing with Legacy Codebases? Find me at ThatConference!

By | Uncategorized | No Comments

I’m honored to have been selected to speak at ThatConference Aug 11th-13th at the Kalahari Resort at Wisconsin Dells. I’m giving my talk OMG! This Codebase Sucks! which tries to lay out some ideas to help people fix up problematic codebases while continuing to deliver value via new features, bugfixes, etc. My goal for the talk is to help attendees learn how to decide which parts of the system and environment to focus on, and how to figure out which sections of the codebase to start tearing apart or outright burning down and rebuilding. All of this has to be…

Read More

Learning Xamarin: Deleting From SQLite

By | Xamarin | One Comment

In this post, we’ll add the ability to delete from the database. Delete Criterion As you may remember, we have Appliances (e.g., Dishwashers) and within Appliances we have Items (e.g., Maytag 100) and within Items we have Criteria (e.g., Quiet, Price, etc.). Criteria are shared among all the Items within an Appliance type. Sometimes we want to get rid of one or more of the criteria. We’re going to allow the user to delete a criterion (e.g., Price) just by tapping on it. We first add the tap handler to the XAML in the ListView of DetailsPage.xaml,

Read More

Kendo UI Grid Custom Columns: How to Show a List of Links

By | JavaScript, Kendo UI | 6 Comments

Of all the Kendo UI web components, the grid component is without a doubt the component that gets used the most in my latest projects. And on top of that, it is the component that gets the most requests for customization. Telerik’s example code is great and often takes us most of the way to our goal, but I thought I would share a few custom column examples that  have proven useful with the Kendo UI Grid. This first example uses data that has an array property, but we want to display that array data as a single column.  A…

Read More

Getting Rid of Buttons to Prevent Inadvertent Input

By | .NET, Blogs, C#, Fun, Microsoft, Mobile, Windows | No Comments

In my other life, I fence with swords. My wife and I also run fencing tournaments. We are known for running a tight ship and keeping things moving along. I hate starting events late, and I hate events running long. Even when you prearrange everything up front, your best plans can be blown apart with simple equipment failure. It’s good practice to have a simple timer for timing the fencing bouts. Several smart phone apps allow you to track all aspects of a fencing bout, like time, score, penalty cards, match count, and injury timer. All of this is represented…

Read More

Using Xamarin Forms DependencyService and Azure Mobile Services to Add Authentication to Cross-Platform Apps

By | Xamarin | 8 Comments

We previously looked how to create a Xamarin Forms App using Azure Mobile Services for storing and retrieving data. However, up until now, we have been saving the data globally so that it is accessible to all users. This post will explore how to add device-specific authentication to each app so that users can register and manage their own private data using any of the supported authentication providers.

Read More

Loading Indicators and Automatic ViewModel Refresh in Xamarin Forms

By | Xamarin | 7 Comments

This is post 4 of 5 in the series “Azure Mobile Services and Xamarin” This post continues the series on building a cross-platform app with Xamarin Forms. Although the focus is to demonstrate using Azure Mobile Services, there is a lot that we can do first to improve the user experience of the app. Today we will look at how easy it is to add a loading indicator as well as automatically refresh the app views when changes are made. ActivityIndicator Xamarin Forms includes a handy ActivityIndicator control which can be used to indicate that a long-running process is occurring….

Read More

Image Sprites made easy with Web Essentials

By | ASP.NET, Web | 2 Comments

In one of my previous posts, I showed you how to keep your Visual Studio Web Essentials settings in sync with the rest of your team. Today I’ll demonstrate one of the hidden gems in this great Visual Studio extension: creating image sprites. Image sprites will allow web browsers to load images dramatically faster and with Web Essentials, they can be created without much effort!

Read More