In Windows Phone 7, 8 and 8.1 Silverlight apps this is very easy: you just set the Opacity of the Application bar to any value less than 1 as described here, and the app does not reserve space for the app bar – it just displays the bar on top of the main UI like this:
The problem is, if you set the opacity of what is now called the CommandBar in Windows Phone 8.1 Store apps, the Application bar is translucent indeed - which you can see if you open it - but the apps still reserves space for it in it’s closed state:
The fix for this is surprisingly easy, but also pretty hard to find if you don’t know what you are looking for. In the end I got a tip by mail from my famous fellow MVP Rudy Huyn. You just add the following, not very obvious line of code to your app. I added it to my App.Xaml.cs, just before the line “Window.Current.Activate();”
Right. And then you get what you want (as is displayed in the first image). And once you enter this line of code into a search engine, then you find hits enough, dating back to even April. But well, that did not help me much. Hopefully this simple article will save someone else a fruitless seach ;)
To make this code compile, you will need to add a “using Windows.UI.ViewManagement;” on top of your file. And although it is in fact an article about code, I will skip the sample download app this time – for just one line of code it feels like a bit of overkill.