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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.

Changing and building parts of CyanogenMod

I have an assignment to take source code of CyanogenMod for certain device, to do some changes (at first, to disable tethering, set custom launcher that my team made, etc...). I managed to get source of CM, rebuilt it and flashed the device with it. I didn't use LineageOS deliberately, since its version is very unstable for this device.
Now, I wish to make some aforementioned adjustments and build ROM with these changes, could someone please point me to the right direction how to achieve it? I couldn't find anything similar to this on the net.
Thanks!

If it's not too late:
you need to find your phone here :
https://wiki.lineageos.org/devices/
and then go to https://wiki.lineageos.org/devices/addison/build
(change addison by your device codeName, which you can find in the "DEVICES" part of this website)
you will find all instructions to build lineageos from sources for your phone, you can then modify these sources to add your custom launcher, disable anything you want...
Cheers

Android game crashed after displaying unity's splash screen

I found this question on different forums but they didn't helped me to find solution of my issue. I had port unity(5.4) game on my android device (OS 4.4). When i opened the game it crashed after displaying unity's default splash screen. I wonder, it was working fine on unity's editor but didn't worked well on device.
Here is the logcat file link. Please let me know if i can provide any additional information that may help to track the issue. Many thanks.
Regards,
Ali

90% it's native plugins. Try to remove all your native android plugins. You can find them under Plugins/Android folder. You also need to remove all links or scripts that uses those plugins. Don't forget to make a back up. If your app won't crash, replace them with some others or connect with plugin development support.

I found the solution. I followed following steps.
Solution
Go to 'Player Settings' -> 'Other Settings'. Uncheck Auto
Graphic Api. Remove 'OpenGLES2' from list.
Test your game on better android device. In my case i tested on Samsung Glaxy S5.
If solution doesn't work
Remove all objects from scene. Port the project and test, if that
works, it means you need to remove unnecessary objects from scene
that need a lot of render power to load on mobile device.
Make sure your Android SDK is uptodated a long with JDK.

Just make sure Virtual Reality support is unchecked

Xamarin Android deployment not using the latest code?

I'm creating an Android app in Visual Studio. When I create the aligned APK to side load on my device (from the Tools -> Android -> Publish Android App), it installs and runs, but doesn't seem to have the very latest changes. The series of events I've experienced is as follows:
Installed a version of the app on my device
Updated a color on the login page and set the application theme (among other things)
Re-installed the app
Saw the new theme but not the new color on the login page
Made a random text change on the login page as a test
Re-installed the app
Saw the color change but not the random text change?!
Any suggestions on what I might be doing wrong?

I have experienced similar issues, my go to for fixing this issue has been the following
Clean all projects.
Build all projects (especially the project containing the xcml files).
Delete (remove application) from the device.
If for some reason this doesn't solve the problem, typically a full restart of Xamarin Studio or Visual Studio does.

I have a similar weird problem where old code from only a single project doesn't get updated. All other projects do get updated/deployed. It only happens on a single emulator, only in Debug mode, and only for that one project.
Cleaning+rebuilding the entire solution did not work. However, telling VS to rebuild the individual project does.
Why doesn't rebuilding the solution rebuild the project? I have no freakin' clue, but I can consistently reproduce this issue and workaround.

In my case, I had a similar problem with connected device, and no one proposed solution like Clean\Rebuild\Restart\Reinstall\etc could help me.
At the same time on the AVD everything worked perfectly, latest code deployed ok.
I found that asked issue depended on selected settings in the [USB Developer] section on the connected device (mine was Xiaomi smartphone). Because some vendors provide us with too many security settings...
What I found, you have to turn on both USB Debugging & USB debugging (Security settings), and turn off MIUI Optimization (it's true for Xiaomi vendor, but you can check your device for similar options). Hope this helps.

Android Apps wont update

i know that eclipse has a couple of glitches when it comes to updating your app and running it on the emulator, i have tried everything that i have found on the internet. Stopping the adb manually making a new emulator and starting it with "wipe user data" and restarting it even reinstalling all of the programs. What i have noticed is that it updates correctly until i start adding images to the drawable folder. After that it doesn't update at all. Can anybody help me its really frustrating also the pictures show up on the "graphic layout how they are suppose to it just doesn't update.

When you add images/resources to the project Eclipse sometimes (always?) doesn't realize anything changed. So then when you run the project, you are just running the last version.
A simple way around that is to change one character of code, change it back, and then run your project forcing Eclipse to recompile and upload the new project with the new resources to the device/emulator.

Do you use 9-patch images? If yes - they should be valid. Once I added an invalid 9-patch image and as a result my Eclipse failed to build the app while it had not informed me what was wrong, so I spent some long time figuring out what it could be.
Another idea - image file name should only consist of a-zA-Z_ chars. Yes, commonly used '-' (minus) char is not allowed.