ListPicker control crashes app inventor 2 (ai2) when selected - app-inventor

I am having a problem programming the Pizza Party example http://appinventor.mit.edu/explore/ai2/pizzaparty.html in ai2. The biggest problem is that I can't even connect to Pizza Party using the 6 letter code.
I am able to get around this by successfully connecting one of my other projects using the 6 letter code and then switching projects to Pizza Party. The app shows up on my android screen, but when I press either ListPicker, the list displays momentarily and then the screen goes black, subsequently prompting me for the 6 letter code again.
I am able to successfully press the submit button of the app so that's why I suspect the ListPicker. I disabled all the blocks to make sure the code behind wasn't crashing silently.
Can anyone shed light on why this is happening and how to overcome it?
PS: I have never been able to get the QR code scan to work

OMG I found the answer posted elsewhere! It was a Developer Option on the phone that caused the issue: https://groups.google.com/forum/#!msg/mitappinventortest/5xq5NlPXFA4/RBg6_gHcCgAJ
Thanks Peter Bowers!

Related

Minmizing OpenGL app while preserving EGL Context results in HUGE PROBLEM

I'm using opengl es 3.0 API with the android studio ndk to create apps.
But I've encountered a very huge problem. I've created a demo app, all it does it change the background color of the screen from white to black and vice versa, every frame. And so when I go to minimize this app, I still see it rendering the background, mostly at the edges of the screen, and not in full color but still very strongly apparent. And it doesn't go away when I close the app, when I restart the device, or when I run "kill apps" on it. Only a factory data reset fixes the issue, so it's not easy for me to debug this.
This is the relevant code that I'm using for when the app is minimized and receives the APP_CMD_TERMINATE event:
eglMakeCurrent(engine->display,EGL_NO_SURFACE,EGL_NO_SURFACE,EGL_NO_CONTEXT);
eglDestroySurface(engine->display,engine->surface);
engine->display = EGL_NO_DISPLAY;
engine->surface = EGL_NO_SURFACE;
I've error checked that eglDestroySurface() is successful.
And I've put debugging messages in to make sure that the main draw loop is NOT executing when the app is minimized. But the problem persists and I don't know what to do about it. Thanks for any help.
UPDATE: well, no one has responded, and I still don't know what to do. Could it be related to threads?
UPDATE: Still can't determine what it is, but for some reason it's messing with the System UI. Willing to upload my entire source code somewhere if someone would be willing to go through this with me, as I'd really like to be able to continue working on my game engine.
Is it the "Strict Mode" developer option on the device settings, perhaps?
That one flashes the screen if an app is blocking.
It would explain why a factory reset changes behaviour.
The answer is not a solution here. The above comment by the user columbo was correct.
I've demoed switching from black to white at high framerates on 3 different android devices, and also my Linux Desktop, all via the openGL api, and it has exhibited this issue on all the devices. So what he said must be correct: this is a problem with LCD monitor technology itself. Interestingly, doing completely random colors does not cause this problem.

How to track a customer only bug

Scenario:
A customer is reporting bugs in a near useless fashion "sometimes when i press button A it does not work".
There story is constantly changing every time you talk to them "button A seems to go wrong after pressing button B" "now button A goes wrong after pressing button C" "Button A goes wrong irrespective of buttons B and C it was all just coincidence"
I have a test rig in my office and can see button A working perfectly, i have never had any issue and cannot replicate the customers problem no matter how many times i try.
management are 120% sure the issue is in the code, no chance that the issue is with the customers button A hardware.
What steps can be taken to trace this issue ? What do you do to show you have covered all possible bases before informing management the code is not the problem and you cannot fix it.
Edit: the software is embedded firmware not an application running on a computer.
As your customer is on the other side of the world I'm guessing your office hours are different and that's what makes it difficult to see what they're doing remotely. If the office hours isn't an issue, then you could ask them to let you watch their screen whilst they attempt to reproduce the issue. Software which could help this remote viewing process includes:
Join.me (FREE)- http://join.me
LogMeIn - https://secure.logmein.com/
GoToAssist - http://www.gotoassist.co.uk/remote_support/
amongst others.
If remote viewing isn't a possibility, another option might be to ask them to record the process, by using Steps Recorder (this is built in to Windows 7 & 8, so only useful if they're using one of these). A guide on how to run it is available here:
http://pcsupport.about.com/od/toolsofthetrade/ht/problem-steps-recorder.htm
They could then send you this file which would mean you could see exactly what they're doing and what the outcome is.
Often what's going wrong is that the customer is omitting some detail that seems insignificant to them (always makes sure to submerge everything in water before use, for example), but is actually the other part of the cause. Ideally, you want as much detail as possible. If practical, visit in person to see the bug in action. If not, see if they can make a video recording of start to finish.

Windows Phone XNA Games Hangs on Resume when Guide is Visible on WP7.x

My Windows Phone XNA game calls Guide.BeginShowKeyboardInput to get the user's name. While the Guide's input screen is shown, if the user presses the Home or Search (hardware) buttons, the game is deactivated as usual - but if the user then presses the Back (hardware) button, the game should resume but it doesn't. Instead it shows the "Resuming..." message until Windows Phone gives up trying to resume the game and kills the process.
Please note:
My app is failing Microsoft certification because of this problem - I really need to fix it!
This only happens in my game when the Guide input screen is shown - when it's not shown, the game
resumes properly after being deactivated.
This problem only occurs when the game is run on WP7.x (verified problem on WP7.5 and
WP7.8) - although the game seems to resume properly on WP8 devices.
I've created a blank XNA game project, called Guide.BeginShowKeyboardInput and tested it using WP7.x devices, and this problem-behavior doesn't occur.
I've tested the game without enabling Music & my Trial License manager (they use timers) and it still does this.
Exact same behavior occurs in the emulator (resume-failure on WP7.x emulators, works fine on WP8
emulator)
I used threads to asynchronously download content during the loading screen - but they already completed and exited.
I don't believe other threads are running, although this seems like
it could be a thread-blocking issue.
Any other ideas on what could be blocking the game from resuming when the Guide.IsVisible or how to debug/resolve this problem?
The solution to this issue was simply to NOT use SuppressDraw when dealing with any operation that passes control outside of the app, e.g. Launchers, Choosers and the Guide.
Have you tried calling "Guide.EndShowKeyboardInput" in either the Deactivating or closing events?
So that the guide is closed before the app suspends, you do get 10 seconds to suspend so this might be worth looking into.
If you want the guide to re-show on resume, then in your state saving code just have a flag and open the guide if it's set.

WP7 Screen Shot Requirements

Microsoft declined to submit my application because I took a screen shot of the game which included the actual emulator.
Looking at this answer, the person says that I should us the snipping tool when I have made the phone emulator at 100%. And indeed, the snipping tools spits out an image of that screen at exactly 480x800 which is exactly what Microsoft wants. However, whenever I use the snipping tool, there is still the top black border of the WP7 remaining. I've looked at a few images on the Marketplace and other applications have it as well...I think. Some don't. Can anyone advice me on this please? How I can avoid getting penalised...again.
Will this suffice?
If you update to the Windows Phone 7.1 SDK and Emulator, the new emulator has a built-in screenshot function to take screenshots without these issues.
I have never had my app rejected due to a screenshot taken from the emulator, I can't say you wont have issues, but assuming everything else in your screenshot checks out; the images from the emulator are the correct size and should be approved.

I have built and made a .zip of my app. Now what?

I'm brand new to app programming, so hopefully, this should be a pretty quick question. After using XCode, I've built and made a .zip of my app. It's stored on my desktop for easy access.
Now what? Do I have to do anything specific before I begin the submission routine for iTunes? Or is the zip all I need to begin submission?
I've been reading http://www.idev101.com/code/Distribution/checklist.html, and it looks like I just finished Step 3. Step 4 shouldn't be too difficult, but I'm a little confused about Step 5. How and where do I select this SKU?
Once that's sorted out and Step 5 is finished and I'm on Step 6, how do I take these specific sized screenshots? Do I just open the iPhone simulator and cmd+4 the window content?
After that, what should I do? Help!!
As you can tell I'm a little overwhelmed! Any advice anyone can give me will be really helpful. I don't want my app to be rejected because I screwed up somewhere.
Which, brings me to my final, hopefully I'll never have to worry about them, questions... if my app is rejected for some reason or another, am I allowed to make changes and resubmit? Or am I out of luck?
Thanks so much!
Step 5 -- The SKU is just a # you put in that is supposed to help you keep track of your 'product' - the app. It can be anything, it's only used to help you (SKU = product ID #)... make one up for your app. Enter it on the same form you enter the description.
Step 6 - Yep, take the screenshots within the simulator, that's the easiest way IMO.
If your app is rejected, you can keep re-submitting til it gets in the store. Just remember it takes some time (was about a week for me) to review each app submission.
Hope this helps!
You can make screenshots easily by pressing the Home and the Sleep button on your iPhone / iPad simultaneously. The screenshot will be saved as a Photo on your Device.

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