Tag Archives: windows store apps

Microsoft answers Windows Runtime questions

I watched the Windows Runtime (WinRT) “Ask the Experts” session from Build 2012; I did not get to attend in person as it conflicted with Herb Sutter’s session on C++. The session was chaired by Martyn Lovell.


Here is what I thought most significant or interesting.

  • Microsoft knows that certain types of apps cannot be implemented as Windows Store apps. The implication is either that the desktop will never go away, or that some future version of Windows Runtime will have extended capabilities. Kamen Moutafov: “There are certain types of system management, system configuration applications that you cannot write a Windows 8 style app for. The platform is not well suited for this type of application.”
  • The WebView control is a problem. An attendee reported z-order, memory, input, and performance issues. This is not only because it hosts the IE10 engine, but also because the system does not cope well with the runtime layers involved: JavaScript running within XAML in a C# app, for example.
  • Someone asked why WinRT apps cannot span or support multiple monitors. The answer, only half joking, “Jensen Harris said that is how it is supposed to be!” Second answer is that this may change in future, and perhaps was just too hard to do well in version 1.0.
  • There was considerable discussion of usage of asynchronous APIs (typically using Async and Await). Can you use them too much? The answer is that you can, and some apps perform badly as a result. An example of a bad usage would be to iterate through many hundreds of files in a directory and fire off an async call for each of them. Lots of aysnc calls returning together will choke your app. Advice is to try limiting the number you fire off, for example, only processing the first page or two that is visible in the user interface.
  • Someone asked how can WinRT apps communicate with desktop apps? This is meant to be restricted to protocol handlers and file types, so that the user is in control. Microsoft attempted to block all other routes.
  • Someone had an app in the marketplace that worked on x86 Windows 8, but he discovered that it crashes (does not even load) on Surface RT. How did it pass certification? Answer: Microsoft has seen instances where apps do not behave the same. Certification is not an exhaustive test. Even so, disappointing to make available an app that will not even load.
  • Can a WinRT app create UIs on multiple threads? Yes you can create two views on different threads. See CoreApplication.CreateNewView.
  • How can you detect if a file exists without raising an exception? Apparently this can’t be done. It may be addressed in future.
  • If you are creating a component to be used by other apps including JavaScript apps, it is best to create in in C++. JavaScript to C# to WinRT is apparently sub-optimal.

Watch the session yourself here.

Information Density in Metro, sorry Windows Store apps

Regular readers will recall that I wrote a simple blog reader for Windows 8, or rather adapted Microsoft’s sample. The details are here.

This is a Windows Store app – a description I am trying to get used to after being assured by Microsoft developer division Corp VP Soma Somasegar that this really is what we should call them – though my topic is really the design style, which used to be called Metro but is now, hmm, Windows Store app design style?

No matter, the subject that caught my attention is that typical Windows Store apps have low information density. This seems to be partly due to Microsoft’s design guidelines and samples, and partly due to the default controls which are so boldly drawn and widely spaced that you end up with little information to view.

Part of the rationale is to make touch targets easy to hit with fat fingers, but it seems to go beyond that. We should bear in mind that Windows Store apps will also be used on screens that lack touch input.

I am writing this on a Windows 8 box with a 1920 x 1080 display. Here is my blog reader, which displays a mere 7 items in the list of posts:


This was based on Microsoft’s sample, and the font sizes and spacing come from there. I had a poke around, and after a certain amount of effort figuring out which values to change in the list’s item template, came up with a slightly denser list which manages to show 14 items in the list. The items are still easily large enough to tap with confidence.


Games aside though, I am noticing that other Windows Store apps also have low information density. Tweetro, for example, a Twitter client, shows only 11 tweets to view on my large display.

The densest display I can find quickly is in Wordament, which is a game but a text-centric one:


I have noticed this low information density issue less with iPad apps. Two reasons. One is that iOS does not push you in the same way towards such extremely large-looking apps. The other is that you only run iOS on either iPhone or iPad, not on large desktop displays.

Is Windows 8 pushing developers too far towards apps with low information density, or has Microsoft got it right? It is true that developers historically have often tried to push too much information onto single screens, while designers mitigate this with more white space and better layouts. I wonder though whether Windows 8 store apps have swung too far in the opposite direction.