Develop Reference

Android 3.4+ file encoding error causing projects to fail in loading and file to become unreadable

Ever since i upgraded to android studio 3.4 and going forth to 3.5.3 and i been experiencing projects that i used to work on earlier in the day suddenly fail to load and modules can't be read and opening any files .xml , .gradle all i see is the something like below:
I tried :
resetting the encoding to UTF8 from android studio settings > editor
invalidating the cache and restart
delete the .idea folder and reloading project
Nothing works, unless i have a copy of the same project or have it on Github and clone it again and re open it.
Note:
while the files look like the image you see in android studio, opening any of them in an editor like VScode shows the correct contents of the file
Anyone have a clue, because this is really frustrating

TL;DR
disable Dart and flutter plugins in File > settings > plugins menu,
reopen your project like you usually do.
Extra steps that could help:
clear cache
delete the .idea folder
delete all .iml files from you project as suggested by #Max Shwed
How i got there:
The issue mentioned above kept happening in a number of android projects old and new.
before uninstalling AS an reinstall i thought i give it one last try, i cleared the cache, delted all the the .iml files manually along with the .idea folder.
After that i imported the project and let AS regenerate the deleted files, one weird thing happened is that my build.gralde file was looking totally different there was Dart code inside it and package import from dart, while the file was completely unaltered when opened in any text editor (thankfully AS didn't re-write the file) it was simply built differently in AS view.
Suspecting Dart plugin to be the problem since i have some demo Flutter apps i been working on , i disabled the Dart plugin and just re-opened my project and Voila everything looks fine and project built successfully and run.

i think it's flutter framework issue
but i have a solution that i tried and fixed this
just make right click in your distributed file -> local history -> show history -> and revert one step
it will get your original code without any formatting
and wait for the next flutter plugins to update

Android studio strange behaviour with some files appearing different than how they are

I have a problem with Android Studio that happened all of a sudden today when I opened AS.
As you may see in the pictures, some files are strange.
In this picture you may see that some of the .java files have different icon
And totally wrong content
Same thing happens with SOME of the XML files which have different content
Also some of the PNG images are not displayed in AS.
All files are ok, if for example I open them externally (notepad...) they are ok (luckily).
Is there a way to fix it?
I've already tried to invalidate cache/restart but it didnt work.
Thanks

So, it happened once again, but I've found a quick fix.
I post it as an answer so people can easily spot it.
Quick fix:
Go to the folder "C:\Users\"your user"
Rename the folder ".AndroidStudio3.2" in ".AndroidStudio3.2backup"(name is example)
Launch Android Studio, It will not find configuration files, so it will ask you if you want to import them from the folder ".AndroidStudio3.2backup"
Click yes, few seconds and now you can delete the backup folder cause it will be created another ".AndroidStudio3.2" folder. Notice that I've renamed the original folder instead of delete it for security, and so to avoid to reconfigure Andoid Studio again, but you can choose to start a new configuration if you want.
Once launched Android Studio, click import (gradle...) and import your project.
Everything worked fine after this few seconds quick fix.
Hope it helps.

In fact this problem has been reported to the Android Studio team already.
A workaround would be to delete the caches folder of the Android Studio directory:
C:\Users\USERNAME\.AndroidStudio3.3\system\caches
This at least is the recommendation from the issue tracker and worked for me as well.

The same happened to me when I updated the libraries in gradle kotlin, etc. what I did was to download my project from my version manager and update the libraries one by one and prove the project works.

How to refresh A Project in Eclipse

I have been studying Android on Eclipse Mars for some time and i have been facing a constant problem everyday-the changes made in a folder/file are not recognized by some other folder/file. For example, if i create a new layout in the layout folder and then use it in the setContentView, it shows me an error ("layout-name cannot be resolved or is not a field). It works if i save the project,close it, and open it again, but this takes up a lot of time if i have more than one error, so the question-is there a way to save and refresh the project (without having to close it) so that the newly made files and folders are recognized by the java files?
Thank you.

You can refresh your project in Eclipse by right clicking on the project root folder in your Project Explorer and selecting "Refresh".
You may also want to consider checking if you have "auto build project" turned on. In your top toolbar go to Project -> Build Automatically.
If build automatically is turned off you will have to manually build your project, by Right Clicking on the project in your Project Explorer and selecting "Build Project".
However, I do agree with Pankaj Nimgade that Android Studio is likely a better entry point IDE for Android development.

Real advice: Switch to Android Studio as soon as you can. There you would sometimes have another problem called "sync" though. But it's a much better IDE and you are at least in line with Google.
on Eclipse, F5 should do the trick. Or right click your project and Refresh. Or Clean all projects. If you are still stuck, simply close Eclipse and run it again.

Messed up in Eclipse after viewing a sample project

I imported a sample 4.0.3 project and after deleting it from the Project Explorer list every thing is lost, now there are none of the projects that I was working before in Package Explorer??
Moreover now on importing these old project For Example name "On" are coming with the name "OnActivity" but still not able to run.
Else in workspace every file is ok, I tried to CLEAN but still no effect.
I'm new to devlopment kindly guide me.

Recover the source code from your workspace in the Windows file browser. If all attempts to recover fail, you can just create the projects from existing (recovered) code.
And what project are you trying to run? If APIDemo or QAActivity, the log shows you why you can't run them.
And instead of using the Play button (start) to launch, use the dropdown triangle and select the project to run, else the XML will be run (obviously that won't work).
Furthermore, make sure Eclipse knows it's a Android Project you're trying to run.

"Android Library Update” eclipse task randomly stuck my eclipse on start

It is stuck in cleaning output folder for “Project”. It is not always the same Project. So is there some workaround ?

I tried the method of cleaning the project, but the library update happens too fast. I even assigned a custom keyboard shortcut to Clean and I still couldn't get it in there before it started.
I really didn't want to delete the .metadata folder because it is a pain in the arse to lose your workspace settings/preferences/setup.
So I tried:
Make a copy of the .metadata folder
Delete the original
Launch eclipse (it will open with a default/reset workspace), but it will open fine.
Quit eclipse
Delete the new .metadata folder
Make another copy of your original copy and rename it .metadata (basically put the original back)
Eclipse should now launch fine. In my case the Android Library Update still ran but it actually finished within a few seconds instead of hanging.
Then for me the underlying issue was one of my library projects got into a really broken state. I went into the properties for it, unchecked isLibrary in the Android tab and then refreshed the project. Afterwards I turned the library flag back on and did a clean.
I also had a build error in the library code that had to be fixed.
Any how, hopefully that helps if you find yourself in a similar position. Good luck!

So while I asked this question I found workaround for me , and possibly for others. You have to kill eclipse and on next start , do clean up on all projects before eclipse start that “Android Library Update” task and it will not stuck eclipse.

Deleting the .metadata folder works to get Eclipse back up and running, but after importing Android projects into the workspace the problem came right back for me.
In my case the underlying cause turned out to be the "Android Library Task" being stuck on trying to access the network. I'm connecting to the network via a proxy, and despite being configured in the global OS network settings and all other applications working fine, Eclipse was still unable to access the network. The only thing that worked was, after deleting the .metadata folder to get Eclipse running, manually entering the proxy configuration in "Preferences->General->Network Connections" to match that of the OS network settings.
Now the "Android Library Update" takes a second on startup instead of getting stuck.

In my case the other mentioned methods did not work for me
but "Reinstalling Eclipse and its all plugins" related to my project did.
After doing that it came to the normal state.
My env;
Eclipse Juno (under OS X Mountain Lion)
GWT
ADT
SVN

Another trick that works is to kill Eclipse, delete the ".metadata" folder from your workspace and restart Eclipse.
It'll force your workspace back to its initial state and clear up any hung conditions.

Since installing Eclipse 4.2 I have had to resolve this problem twice. The second time I knew that the only thing that worked for me was to create a new workspace and import the projects from the "broken" workspace. It is very fast and is a good opportunity to de-clutter by leaving obsolete projects behind.
Specifically,
choose File/Switch Workspace/other and put in the name of your new workspace.
Then right click in the Package explorer of the new workspace and choose Import and select Existing Android Code into Workspace.
Then browse to the root of a project that you wish to import and also select Copy projects into workspace.
Hit Finish.
You will have to do the same for any projects that this project is dependent on such as google-play-services.

Recently experienced this, caused by an Annotation Processor throwing an uncaught exception. Killed Eclipse, removed references to the offending Annotation from one project .java file, and started successfully.

In my case, within Eclipse, I had set up a C/C++ Builder to invoke build_native.sh, which is needed to build cocos2d-x. Interestingly, the Android Library Update indicated that it was invoking build_native.sh ! For me this explains why it was taking so long sometimes and seemed to be taking a LONG time to finish. I basically replaced this with an echo command. echo "do nothing" and I think this resolved the hanging issue.
This seems pretty goofy to me -- AFAIK, there's no way to configure 'Android Library Update', and I'm not sure why it's doing what it's doing, since Eclipse has a number of build options which the user can manually control.