Bitesized tidbits for building Modern (Metro) apps.
Windows Phone update codenamed Tango is coming soon and with it comes devices that have a lower amount of memory in them than the usual 512mb, specifically 256mb. Your app needs to take into account whether it should be able to run on phones with 256mb of RAM and is discussed pretty well on MSDN at http://msdn.microsoft.com/en-us/library/hh855081(VS.92).aspx. So is there a quick way in your app of seeing whether the device your app is running on is 256 or 512mb? Yes, and is touched on in that MSDN link, I decided to just extend the code they give to give a quick and easy property that you can have in your app/viewmodel.
The AppHub and Marketplace support private betas which as a developer is great, you get to give it to real people who might not necessarily have a developer unlocked (or ChevronWP7 unlocked) device. This is done by you submitting an app to the AppHub in the same way as you would with a normal app, but with one difference, in the first page, you change this option:
Once this goes through, you can then give your beta testers a zune link and they can access the app through their phone’s MarketPlace hub. Part of the process of submitting a beta app is providing a list of Windows Live IDs, and these WLIDs are the only ones that have access to the beta.
The acceptance on beta apps is a lot quicker than a normal app as there aren’t as many checks done so you should receive a confirmation within a few hours to say it’s approved and will give you your zune link. Now, here’s the problem: there’s no way of knowing exactly how long it will then take from approval to visibility, especially with how slow the marketplace is at the moment for displaying new apps. There’s no real way of seeing when your app is available in the marketplace to your testers. Or is there?
So you’ve published your paid for app, you included a trial to hook some people in, great. You look at your download figures in your app list on AppHub and the figures are looking good, great! Roll on that fat royalties cheque from Microsoft. But wait a minute, you included a trial, so could these figures just all be trial downloads? They could be, but it’s not quick to find out, so let me show you.
There are a few things I’ve been doing to work around a couple of scenarios when it comes to using the ListBox in Windows Phone. The first is when your ListBox has no items I want it to show something to the user stating there are no items, the other involved limiting the number of items that are enabled based on whether the app was in its Trial Mode.
The first scenario had seen me using a TextBlock and a ListBox and hiding one or the other depending on how many items were in the ListBox, it wasn’t really ideal. The other scenario, well, I didn’t have any workaround for that, but I already had what I’m about to show you done for the first scenario, so modified it for the second scenario. Read on to find out more.