Failed Win8 App Certification: 3.10 - If your app includes an ARM or a Neutral package it must support Microsoft Direct3D feature level 9_1 - windows-8

My C# app uses a C++ WinRT component I've written to get a list of system fonts using Direct X.
This is based on this example:
http://msdn.microsoft.com/en-us/library/dd756582(v=VS.85).aspx
My app is published in the store, but my latest update failed to pass the store review process on point 3.10 complaining about my use of Direct 3D and how this might not run on ARM tablets. As far as I know I'm not using Direct 3D and the only Direct X feature I'm using is GetSystemFontCollection.
How can I make sure I don't fail this requirement and do I need to remove some rogue reference in my component to Direct3D?
Also, why am I failing this now, when it passed before?

Did you target all three platforms or choose any cpu in your release?
Does this page help:
http://msdn.microsoft.com/en-gb/library/windows/apps/hh994923.aspx
It looks like you may have inadvertently requested a higher level.

I submitted again and included a note to the tester explaining that my app didn't use any Direct 3D features, and I told them the exact DirectX function I did use.
I still failed, but the Direct3D reason was no longer one of the reasons.
Apparently my app is crashing, which was another failure reason the first time round, but I thought this must be related to the Direct3D problem. I can't reproduce the crash, but at least I now know that I can stop looking at my use of DirectX. This was a red herring.

Related

Applying Non-Standard Power Assertions & Creating Virtual HIDs

I've got a big ask here, but I am hoping someone might be able to help me. If there's another site you think this should be posted on, please let me know.
I'm the developer of the free app Amphetamine for macOS and I'm hoping to add a new feature to the app - keeping a Mac awake while in closed-display (clamshell) mode while not having a keyboard/mouse/power adapter/display connected to the Mac. I get requests to add this feature on an almost daily basis.
I've been working on a solution (and it's mostly ready) which uses a non-App Store helper app that must be download and installed separately. I could still go with that solution, but I want to explore one more option before pushing the separate app solution out to the world.
An Amphetamine user tipped me off that another app, AntiSleep can keep a Mac awake while in closed-display mode, while not meeting Apple's requirements. I've tested this claim, and it's true. After doing a bit of digging into how AntiSleep might be accomplishing this, I've come up with 2 possible theories so far (though there may be more to it):
In addition to the standard power assertion types, it looks like AntiSleep is using (a) private framework(s) to apply non-standard power assertions. The following non-standard power assertion types are active when AntiSleep is keeping a Mac awake: DenySystemSleep, UserIsActive, RequiresDisplayAudio, & InternalPreventDisplaySleep. I haven't been able to find much information on these power assertion types beyond what appears in IOPMLibPrivate.h. I'm not familiar at all with using private frameworks, but I assume I could theoretically add the IOPMLibPrivate header file to a project and then create these power assertion types. I understand that would likely result in an App Store review rejection for Amphetamine, of course. What about non-App Store apps? Would Apple notarize an app using this? Beyond that, could someone help me confirm that the only way to apply these non-standard power assertions is to use a private framework?
I suspect that AntiSleep may also be creating a virtual keyboard and mouse. Certainly, the idea of creating a virtual keyboard and mouse to get around Apple's requirement of having a keyboard and mouse connected to the Mac when using closed-display mode is an intriguing idea. After doing some searching, I found foohid. However, I ran into all kinds of errors trying to add and use the foohid files in a test project. Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app? I'm not asking for code help with that (yet). I'd just like some help determining whether it might be possible to do.
Thank you in advance for taking a look.
Would Apple notarize an app using this?
I haven't seen any issues with notarising code that uses private APIs. Currently, Apple only seems to use notarisation for scanning for inclusion of known malware.
Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app?
Taking a quick glance at the code of that project, it's clear it implements a kernel extension (kext). Those are not allowed on the App Store.
However, since macOS 10.15 Catalina, there's a new way to write HID drivers, using DriverKit. The idea is that the APIs are very similar to the kernel APIs, although I suspect it'll be a rewrite of the kext as a DriverKit driver, rather than a simple port.
DriverKit drivers are permitted to be included in App Store apps.
I don't know if a DriverKit based HID driver will solve your specific power management issue.
If you go with a DriverKit solution, this will only work on 10.15+.
I suspect that AntiSleep may also be creating a virtual keyboard and mouse.
I haven't looked at AntiSleep, but I do know that in addition to writing an outright HID driver, it's possible to generate HID events using user space APIs such as IOHIDPostEvent(). I don't know if those are allowed on the App Store, but as far as I'm aware, IOKitLib is generally fine.
It's possible you might be able to implement your virtual input device using those.

Setting SDK version fallback resource values in UWP

My application is compiling against Windows Creators Update (15063), but is supposed to run on a minimum version of 10586; however, some colour resources we used seem to be missing on old versions.
The exact whereabouts of failing resources are unknown (as the incompatible resources are), so temporarily, I want to give a global fallback value to eliminate crashes on old SDKs.
Is there any programmatic C# or automatic XAML way I can do it?
You could check whether certain features are available at runtime. There are many ways how to achieve that. You can read more about how to write version adaptive code for example here and here.

Webkit Wrapper for Desktop Apps

I have a desktop app based on HTML/JS that needs WebKit to function at a reasonable speed. Normally, I would live with IE behaving badly, but its JS engine is just too slow.
I would normally go to Appcelerator for this, but it seems they have discontinued their desktop SDK and left it for the "community"...
This needs to function on Windows PCs, or I would just use Fluid (http://fluidapp.com)...
Is there a simple Webkit wrapper that I can use, or should I build one really quick in something like Qt. I haven't used Qt in a while, so I'd have to look at it again and make sure WebKit is implemented in it...
While it is somewhat node.js-oriented, AppJS may offer what you're looking for. If it doesn't already support other scripting languages, it might at least provide a good example to start from.
Update: in the time that's passed since my original answer, it seems node-webkit fills a similar role but has gathered and maintained more momentum than AppJS. It's a little more focused, in that it doesn't attempt to provide much additional "framework" on top of simply exposing the node.js API to the window's JS context.
There's also https://github.com/atom/atom-shell, which I just learned of and may be similar.
One other thing to note is that (presumably with either, but at least with node-webkit), you MUST be cautious of any XSS-like vulnerability in your app that an attacker could exploit to gain complete access to the user's native machine. So if you are simply needing to package an offline web app in a downloadable desktop distribution, you may wish to research more PhoneGap-like solutions (e.g. Mac OS X as PhoneGap platform) or a plain web view wrapper (like mentioned in the OP) that do not expose an entire OS-level native API — as node.js does — into the JavaScript environment.

Discover calls to methods not available in earlier iOS versions

I am building my app using iOS 5.0 as base SDK and iOS 3.0 as deployment target.
I know I need to check for existence of methods and classes when I work with features that are not available in the earlier iOS versions, but lately I've lost a few hours on a problem just to discover I was calling a method not available in some iOS versions. I simply did not notice it was a new method and did no check before to call it. The app of course compiled with 0 errors and 0 warnings.
This is a big problem because if I forgot some other check somewhere in the app, I will not know it until I or, worst, some user will activate that specific part of code.
Maybe I am missing something, is there some compiler option I can set to detect the calls I make to methods not available in the iOS deployment target? How do you deal with such a problem?
This link might point you in the right direction. Supporting mutiple ios Versions in your apps. It explains how to deal with taking advantage of the newer ios features while maintaining backwards compatibility. Hope that helps.
The only way to check for compatibility with a prior version of iOS, currently, it to test the app on an old non-updated device running that version of the OS.
If you can't find a device that old, even just to borrow for short time, then there may not be a good buiness reason to set the Deployment target that low.

Building Cross Platform app - recommendation

I need to build a fairly simple app but it needs to work on both PC and Mac.
It also needs to be redistributable on a disc or usb drive as a standalone desktop app.
Initially I thought AIR would be perfect for this (it ticks all the API requirements), but the difficulty is making it distributable, as the app would require the AIR runtime to be installed to run.
I came across Shu Player as an option as it seems to be able to package the AIR runtime with the app and do a (silent?) install.
However this seems to break the T&C from Adobe (as outlined here) so I'm not sure about the legality.
Another option could be Zinc but I haven't tested it so I'm not sure how well it'll fit the bill.
What would you recommend or suggest I check out?
Any suggestion much appreciated
EDIT:
There's a few more discussions on mono usage (though no real conclusion):
Here and Here
EDIT2:
Titanium could also fit the bill maybe, will check it out.
Any more comments from anyone?
EDIT3 (one year on): It's actually been almost a year since I posted that question but it seems some people still come across it every now and then, and even contribute an answer, even a year later.
Thought I'd update the question a bit. I did not get around to try the tcl/tk option at the end, time constraint and the uncertainty of the compatibility to different os versions led me to discard that as an option.
I did try Titanium for a bit but though the first impressions were ok, they really are pushing the mobile platform more than anything, and imho, the desktop implementation suffers a bit from that lack of attention. There are also some report of problems with some visual studio runtime on some OSs (can't remember the details now though).. So discarded that too.
I ended up going with XULRunner. The two major appeals were:
Firefox seems to work out of the box on most OS version, so I took it as good faith that a XULRunner app would likely be compatible with most system. Saved me a lot of testing and it turned out that it did run really well on all platforms, there hasn't been a single report of not being able to start the app
It's Javascript baby! Language learning curve was minimal. The main thing to work out is what the additional xpcom interfaces are and how to query them.
On the down side:
I thought troubleshooting errors was a sometimes difficult task, the venkman debugger is kinda clunky, ended up using the console more than anything.
The sqlite interface is a great asset for a desktop app but I often struggled to find relevant error infos when something didn't work - maybe i was doing it wrong.
It took a little while to work out how to package the app as a standalone app for both PC and Mac. The final approach was to have a "shell" mac app and a shell pc app and a couple of "compile" script that would copy the shells and add the custom source code onto it in the correct location.
One last potential issue for some, due to the nature of xulrunner apps, your source code will be deployed with the app, you can use obfuscation if you want but that's something to keep in mind if you want to protect your intellectual property
All in all, great platform for a cross-platform app. I'd highly recommend it.
Tcl/Tk has one of the best packaging solutions out there. You can easily wrap a cross-platform application (implemented in a fully working virtual filesystem) with a platform-specific binary to get a single file executable for just about any modern desktop system. Search google for the terms starkit, starpack and tclkit. Such wrapped binaries are tiny in comparison to many executables these days.
Many deride Tk as being "old" or "immature" but it's one of the oldest, most stable toolkits out there. It uses native widgets when such widgets exist.
One significant drawback of Tcl/Tk, however, is that it lacks any sort of printing support. If your application needs to print you'll have to be a bit creative. There are platform-specific solutions, and the ability to generate postscript documents, and libraries to create pdfs, but it takes a little extra effort.
Java is probably your best bet, although not all Windows PCs will necessarily have Java (most should). JavaFX is new enough you can't count on it - you'll probably find a lot of machines running Java 1.5 or (shudder) 1.4. I believe recent Mac OS still ships with 1.5 (latest version may have changed to 1.6).
Consider JavaFX
It would run everywhere with a modern JRE ..!
AIR could be an option, but only if you don't mind distributing two different files (the offline runtime installer and your app), and expecting the user to run one and then the other. You do have to submit an online form at Adobe's site saying you agree to distribute the offline installer as-is, rather than digging out individual DLLs or whatever, before they give you the installer.
Unfortunately there's currently no way to get both an AIR app and the runtime to install from one file though. I'm not sure what the deal with Shu is, or whether it's doing anything that isn't kosher.
i would recommended zink. it has all the functionalities you require for desktop. however, the las time i used it it was a bit glitchy.
i was hung up by trying to write a 6M file to the disk. thought it trough and changed the code to write 512K chunks at a time (3min work, fast).
probably it still has some little annoying glitches like making you think on root lvl but the ease of use and the features are just way too sweet to ignore.