Develop Reference

Having some trouble with android studio probably has a simple answer

I'm trying to install android studio, but while I was installing it I got this exception:
My question is what is the Android Emulator Hypervisor? what does it do or enable me to do? I tried looking it up online but I kept getting into these rabbit holes of information that kept expanding and expanding. I just want a concise answer for my small brain and maybe a quick and clear explanation to fix this.

The emulator essentially creates virtual machines running specific Android versions in order to run your apps. The Hypervisor driver is something that can help a lot with performance. If you want to check out the details, this documentation page might be a good start.
To fix your installation issue you only need to follow the link given in your error message, there's not much need to understand hypervisor workings.

Xamarin Forms Android This type of collectionView does not support changes to its sourceCollection from a thread different from the dispatcher thread

Here is the error I'm getting when trying to archive my app for deployment.
This error doesn't show up at any other time. The project builds and runs on emulators and devices without issue. This error has zero context or direction as to where to look to fix it. It also just randomly showed up out of nowhere, last time I built/archived (with zero functional changes) this error did not happen.
Main difference between this archival and the previous one is a newer version of VS 2017. Don't remember exactly the version from before, but am currently on 15.9.4 (stable).
Looking around on the interwebs, I've found that this error seems to have something to do with ObservableCollection's, which there are probably 10-ish in my app. Not really sure what to do here, because this has never been an issue previously, and I'm coming up on a deadline and with the structure of the app, am not in a good position to start making functional changes.
EDIT
I have also cleaned and rebuilt my solution, as well as deleting all bin/obj folders in my xamarin projects. Even tried deleting the .vs folder which can sometimes help. But still no go.
Going to try updating VS to 15.9.5 and see if maybe it was fixed in a release.
EDIT 2
Updating VS 2017 to 15.9.5 made no difference.
EDIT 3
I had my coworker try archiving the exact same project on his machine (running VS 2017: 5.9.3, and it archived fine for him. So far that's the only difference we've been able to find between our environments.

I saw the same problem using VS2017 15.9.9. Even the same code that could be archived a week ago threw the above mentioned error. It seems related to local data in the solution. A "clear" build was not sufficient. However manual deletion of the local obj and bin folders followed by archiving (build is done implicitly) solved the problem for me.

For my part closing Visual studio and deleting the .vs hidden folder did it.
It's actually a fix for many issues using Xamarin.
I had this other issue where I couldn't archive because the build process would just hang and never end. Deleting the .vs folder did it too.
https://github.com/xamarin/xamarin-android/issues/1760

Just go to project property then go to Android options-> Select Advanced then increase the Java Max heap size to 2G/3G -> it's working for me.

Leon Lu's suggestion worked. I don't particularly like it, as it took forever and repairing basically restores you to a base install (no extensions or personalizations). Took about 1.2 hours to complete, but once done I was able to again archive my android application. I guess something went wrong in vs at some point, perhaps during an update. There's no way to tell.

I tried ALL of the ideas above, but had no consistent reliable luck with any of them.
I found that Microsoft has had the problem reported to them (see link below). After a ton of time burn on this, I posted at the link below one way that I've been able to get around this archive-build issue.
Like the other fixes, it's not exactly logical, and nothing that you would think would work, but I've found the process to be repeatable, which is golden for me with tight timelines and having no time for this.
MS Visual Studio Developer Community Problem 507708
Posted on a Saturday morning, a sign of really needing to get around this urgently. I hope it helps you too.

Getting an App APK

Hey guys and girls for a the past week I've grown a lot of interest in android studio (even without knowing quite much about it) I decided to create an app that I deemed quite useful. However the app required maps to be integrated in it and I really did not know what I was doing and at one point I started messing with the settings and then all hell broke loose and I kept getting AAPT2 errors and I even tried to fix this issue with the gradle properties line that you add (I forgot the line of code to add). Anyways it still didnt work. However I rembered that I always kept the good version (before I broke everything) of the app on my phone. So when I go in my phone the app is there and it works just fine. Ive tried so many things to get the source code from the app on my phone without any succes. My question is, how can I get the source code back from the working app onto my laptop to continue coding in android studio? If it helps I am using Linux 18.04 LTS and running the newest version of android studio. Thank you for any help from you guys. This means a lot to me.

You can’t get back the ‘source code’ from an already compiled app.
You should consider using some version control platforms like git from the next time

Auto-repair for Android Studio?

Lately I've been having problems with Android Studio, mostly what it seems with code synchronization. For example, I'll comment out a section which is causing the issue and sync the project before running it again, only to have the Android Monitor point out to the line in comments, as if it still interprets it as code. I'm curious what you would recommend? A full reinstall? Is there any feature that restores default settings and would alleviate this issue?
Thanks in advance.

Akavache no such table: SchemaInfo

I am trying to use Akavache with Xamarin.
I've installed Akavache package from NuGet to Android and Windows Phone projects.
Initialization:
BlobCache.ApplicationName = "MyApp4";
BlobCache.EnsureInitialized();
BlobCache.LocalMachine.InsertObject("key", "Value");
Third line throws an error (on both Android and Windows Phone targets):
Akavache.Sqlite3.Internal.SQLiteException: no such table: SchemaInfo
What am I doing wrong?
Thanks in advance :)

The exception is a first change exception, but is handled. So just F5 and continue. Paul Betts explains the reasoning here https://github.com/akavache/Akavache/issues/195#issuecomment-66576874
"Yep, so to explain what this is doing, it's looking for a table that we internally use to do migrations (so that we can change the on-disk format of Akavache without breaking existing data); in new databases, this table is never found, so we have a first-chance exception."

I encountered this with Xamarin.iOS. It got "fixed" but may not be the same cause. And while I don't have a complete explanation of "why", for me the problem appeared to be something awry in the simulator files. By ditching all saved simulator state files the problem went away. The weird thing is that a simulator "Reset Content and Settings..." was not good enough, nor was just switching to a new simulator. (Nor restarts of simulator/XamStudio, nor full cleans/rebuilds etc.) It started working when I cleared all the files for all simulators found in the simulator hidden folders... Or maybe it was the chicken I sacrificed at the same time. Coulda been the chicken.
The location for the iOS simulator files on the Mac changed in iOS8. The following post has both the pre-ios8 and ios8 locations identified: Document Directory Path of iOS 8 Beta Simulator. (Unfortunately ios8 makes it quite a bit trickier to find.)
Possibly the same kind of weirdness can happen in the Android emulators...

I experienced the same issue using Xamarin. My fix was to turn off the System.Exception breakpoint.