Paneque's Technology Blog

While using Visual Studio 2015 to edit and android layout file ( axml ) I got this error:   The installed Android SDK is too old. Version 24.3.4 or newer is required The number version might be different in your case. Here are a few possible causes for the error: 1) You actually need to upgrade your Android SDK. 2) You have the wrong path for the Android SDK installation on Visual Studio. (change it on Tools->Options->Xamarin) 3) Mixed Xamarin extensions (this was my case) After reinstalling the Android SDK and checking the everything was fine on that part I went to check on Visual Studio extensions ( Tools -> Extensions and Updates ). It turns out that  I caused a mix up of versions, since I already had Xamarin and Visual Studio 2013 side by side. and now 2015 had another one, my Visual Studio 2015 ended up with 2 extensions for Xamarin. Disabling one of them solved the problem and the designer was working again. The one that I disabled was titled "...

Did you ever have a problem with a WCF client throwing exceptions you can't catch? If you have used WCF clients from Windows Phone, Silverlight or Xamarin.iOS, you might have noticed that it is not possible to create Synchronous or Task-Based operations; the functionality is reduced to the Event-based Asynchronous Pattern (EAP). That means that the way to call a WCF method and get the response is usually as follows: var client = new MyWCFClient(); client.DownloadDataCompleted += (sender, e) => { try { //accessing e.Result here might raise an exception in another //thread, that will not be captured by the 'catch' below. } catch(Exception ex) { } }; client.DownloadDataAsync(url); Our results are wrapped in an auto-generated class that inherits from  AsyncCompletedEventArgs , this class has a property  Error  of type  Exception , that will carry information about the error and a property  Result  with our expected return valu...

In addition to pizza, caffeine, and video games, a developer requires a lot of tools, and I mean "a lot". Each one is different so here I want to showcase what I use, and briefly explain why. The idea of this post rather than make any type of advertising (notice there are no links at all) is more to actually find out what other people use and share with you all my experience. So, the profile:  .NET Developer. The usual work: Web applications with ASP.NET (Web Forms and MVC) Windows Forms Windows Presentation Foundation Windows Phone Apps iOS Apps  Of course, I might code almost every day a bit of JavaScript and some HTML/CSS fixes, along with some other things, but that's not enough to consider it the main course. The Infrastructure Before coding, organization and planning is everything, and that means for me 3 things, since I am a SCRUManiac: Source Control Issue/Bug tracking Continuous Integration For source control, I prefer Git particularly, ...

One the first entry of this series I covered the issues with the keyboard in iOS not hiding automatically when needed. In this second - and final - entry on the subject I am going to go for the most of annoying issue when creating UIs in iOS. The keyboard overlaps a focused TextField  If you have a TextField below the keyboard top edge position, they will be hidden once the keyboard shows up. The keyboard size is 320x216 points* in in portrait mode, so anything below the 264 (iPhone 4/4s) or 352 (iPhone 5/5s) points won’t be visible.  It is so simple that is almost unbelievable, but it happens as you can see in the images. Since this default behavior is inconvenient we are going for the workaround. The solution is not pretty but it is trivial: we need to place the UI elements inside a UIScrollView  and will use notifications to monitor when the keyboard will Show/Hide and will scroll the content of the container to ensure that views inside are always vis...

When you are a developer for more than one platform, you might find that what is considered basic or pre-built in one, it’s incomplete or completely missing in another one. This entry is about fixing some issues with the virtual keyboard on iOS; especially when it hides your text fields or keeps the input focus. Xamarin Studio/Mono and XCode were used for this example. Hiding the keyboard Tapping inside the TextField will show the keyboard, but it won't be possible to get rid of it by tapping outside or pressing “RETURN” on it. This is something pre-built in Silverlight for Windows Phone. Tapping outside of the textbox or hitting the “back” key will hide the keyboard. But well, there is no back key on the iPhone. So let’s start by creating and extension method that we will use in the rest of the solution. The method will return the view that is the first responder or the “active” one. public static class Extensions { public static UIView FirstRespon...

Popular wisdom says "things happen for a reason". However experience has proved me that when it comes to programmers, that is not always true. Things can just happen for no reason at all. That's why we require feedback, here is one and I assure you is in good spirit. So let's me write about something I found when building an app for iOS using Xamarin/Mono. The invisible property. Ranging from windows forms (desktop or Windows Mobile) to WPF, Silverlight/XAML on the web or windows phone. ASP.NET Web Forms or Razor, MVC or classic. One thing I can say for sure: any visual element  has a way to check for its visual status. Call it "Visible" in windows forms, "Visibility" in Silverlight/WPF. There is always an intuitive, simple and trivial way to know if something - that might be visible - it is visible at a particular moment or not. You can't imagine my surprise when I realized that the UIViewController in iOS does not provide such mecha...