Some time back while I was working on getting the Javascript Windows Store app platform running on Windows Phone (now available on the last Windows Phone release!) I had an interesting bug that in retrospect is amusing.
I had just finished a work item to get accessibility working for JS WinPhone apps when I got a new bug: With some set of JS apps, accessibility appeared to be totally broken. At that time in development the only mechanism we had to test accessibility was a test tool that runs on the PC, connects to the phone, and dumps out the accessibility tree of whatever app is running on the phone. In this bug, the tool would spin for a while and then timeout with an error and no accessibility information.
My first thought was this was an issue in my new accessibility code. However, debugging with breakpoints on my code I could see none of my code was run nor the code that should call it. The code that called that code was a more generic messaging system that hit my breakpoints constantly.
Rather than trying to work backward from the failure point, I decided to try and narrow down the repro and work forwards from there. One thing all the apps with the bug had in common was their usage of WinJS, but not all WinJS apps demonstrated the issue. Using a binary search approach on one such app I removed unrelated app code until all that was left was the app's usage of the WinJS AppBar and the bug still occurred. I replaced the WinJS AppBar usage with direct usage of the underlying AppBar WinRT APIs and continued.
Only some calls to the AppBar WinRT object produced the issue:
3 diff kinds of challenges: Three Trials 
Old war. New battlefield. 
var appBar = Windows.UI.WebUI.Core.WebUICommandBar.getForCurrentView();
// appBar.opacity = 1;
// appBar.closeDisplayMode = Windows.UI.WebUI.Core.WebUICommandBarClosedDisplayMode.default;
appBar.backgroundColor = Windows.UI.Colors.white; // Bug!
I eventually realized that predefined WinRT color values like Windows.UI.Colors.aqua would cause the issue while JS literal based colors didn't cause the issue (Windows.UI.Color is a WinRT struct which projects in JS as a JS literal object with the struct members as JS
object properties so its easy to write something like {r: 0, g: 0, b: 0, a: 0} to make a color) and I had been mixing both in my tests without realizing there would be a difference.
I debugged into the backgroundColor property setter that consumed the WinRT color struct to see what was different between Windows.UI.Colors.black and {a: 1, r: 0, g: 0, b: 0} and
found the two structs to be byte wise exactly the same.
On a hunch I tried my test app with only a reference to the color and otherwise no interaction with the AppBar and not doing anything with the actual reference to the color:
Windows.UI.Colors.black;. This too caused the issue. I knew that the implementation for these WinRT const values live in a DLL and guessed that something in the code to create these
predefined colors was causing the issue. I debugged in and no luck. Now I also have experienced crusty code that would do exciting things in its DllMain, the function that's called when a DLL is loaded into the process so I tried modifying my
C++ code to simply LoadLibrary the DLL containing the WinRT color definition, windows.ui.xaml.dll and found the bug still occurred! A short lived moment of relief as the world seemed to make
sense again.
Debugging into DllMain nothing interesting happened. There were interesting calls in there to be sure, but all of them behind conditions that were false. I was again stumped. On another hunch I tried renaming the DLL and only LoadLibrary'ing it and the bug went away. I took a different DLL renamed it windows.ui.xaml.dll and tried LoadLibrary'ing that and the bug came back. Just the name of the DLL was causing the issue.
I searched for the DLL name in our source code index and found hits in the accessibility tool. Grinning I opened the source to find that the accessibility tool's phone side service was trying to determine if a process belonged to a XAML app or not because XAML apps had a different accessibility contract. It did this by checking to see if windows.ui.xaml.dll was loaded in the target process.
At this point I got to fix my main issue and open several new bugs for the variety of problems I had just run into. This is a how to on writing software that is difficult to debug.
drug companies hiding the results of clinical trials.
(via I did a new talk at TED, on drug companies and hidden data.)
![[Seattle's Best Coffee logo in front of Pike Place logo]](http://www.seattlesbest.com/images/aboutus_b.jpg)
This past
Saturday Sarah and I took the Savor Seattle Tour of various food shops in Pikes Place. Sarah had suggested it at one point and when Jesse and Nicole
brought it up again when they came up to Seattle we decided to go. Surprisingly our tour group consisted of mostly locals. Except for the fish market I hadn't been to see any of the places on the
tour. I particularly enjoyed the chocolate cherries and the tea. Our tour guide Tim was funny and overall I enjoyed the tour and would recommend it. I've made a map of our tour including what free trials we got at each location. Yum!
Sarah and I have finished playing through the games "Paper Mario", "Paper Mario: The Thousand-Year Door", and "Super Paper Mario" last week (including the various Pits of 100 Trials). We played them all on the Wii, because even though Super Paper Mario was the only one released explicitly for that platform, Wii maintains compatibility with Game Cube games such as Thousand-Year Door and Paper Mario although originally released for the Nintendo 64 is now available as a pay for download game on the Wii's Virtual Console. So, yay for Nintendo!
I think my favorite of the three is Thousand-Year Door mostly because of the RPG attack system. In Thousand-Year Door and Paper Mario when you come into contact with an enemy you go into an RPG style attack system where you take turns selecting actions. In Super Paper Mario you still have hit points and such, but you don't go into a turn based RPG style attack system, rather you do the regular Mario jumping on bad guys thing (or hitting them with a mallet etc...). Thousand-Year Door and Paper Mario are very similar in terms of game play but Thousand-Year Door looks very pretty and has made improvements to how your party-mates are handled in battle (they have HP and can fall as you would expect) and there's an audience that cheers you on during your battles.
Even if the gameplay sucked the humor throughout the series might be tempting enough. Mario's clothing and mustache are mocked throughout and standard RPG expectations are subverted. I hate to describe any of these moments for fear of ruining anything but, for instance, an optional and very difficult enemy who may only be killed after hours of work only results in one experience point, or a very intimidating enemy who you imagine you'll have to fight actually challenges you to a quiz.
Despite how I personally rank them, all the games are great and I'd recommend any of them.
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