Use Converters in your Windows Phone Apps

In a recent post I have covered several approaches to store data in a Windows Phone application. Another important problem is presenting data in an easy and controllable way that would not interfere with other layers of your app. To some extent XAML handles this task well, but from time to time just markup is not enough and one needs to introduce a portion of imperative code to present data nicely. To make this possible each binding in a XAML-based app may specify a converter, which will be responsible for transforming data between internal and external representations.

XAML: Event Handlers for Templated Items of Collection Controls

Recently, while fighting my way through XAML required to create a relatively simple UI for a Windows Phone 8 application I have come across some unexpected difficulties. When it comes to hacking markup I prefer to modularize it as much as possible – many of us do. Here we follow the same ideas that govern us when we write imperative code and break it into relatively small and simple functions and classes to assemble them into something bigger on higher levels. The benefits of this approach are well known: better isolation, finer specification of responsibilities and less code duplication. With markup we usually behave worse – the code for pages frequently feels quite monolithic and it is difficult to explicitly split it into parts each of which pursues its own goals. Here XAML gives us ControlTemplate and DataTemplate allowing to improve the state of affairs to some extent. The DataTemplate is primarily used with collection controls so that we can specify the way each element should be displayed. In my specific case the parent control was LongListSelector, which should have displayed a list of more or less complex items.