C#

Making a reverse Autocomplete-TextBox on Windows Phone

I’m sure you’re familiar with autocomplete textboxes and maybe you’ve even used them in a project yourself. They provide a fast and easy way for the user to select something, but they lack one important feature: they don’t show what could be selected. ReverseAutocompletePopup is a mixture between an autocomplete text box and the kind of popup you get when a ComboBox has more than five items. At first it displays all options in a ListBox and as you type non-matching ones are filtered out. (And brought back when you delete the text!) EDIT: In the newer version, the user can hit Enter to select, or optionally use his input as the result. When working with it there’re a few things you need to have in mind: The Popup control is no real navigation-thing, so you are in charge to handle OnBackKeyPress according to the guidelines! The Options for the…

C#

Running a synchronous method in an asynchronous context

In WinRT a significant portion of all native methods are asynchronous. Using an asynchronous method is very easy an can help you to speed up you application. The requirement to use an async method is that the calling method has an async modifier. It’s easy to use async methods from a native API, but it can be useful as well to run synchronous operations off the UI thread. This should be done to prevent the UI thread from beeing blocked by time-consuming or resource-intensive operations like calculating ϖ or the answer to the ultimate question for the life, the universe and everything. To show you how to run things like this asynchronously we take the following synchronous method: private void synchonousMethod() { do { i++; } while (i < Int32.MaxValue / 2); } This method obviously lacks the async and await keywords and it’s usual implementation would be something like…