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How can I recover R.java file

My project was running properly.I just gave a Lint check and it gave me errors from all projects. So I just cleaned my project. But now its not generating R.java file. How can I recover it. I tried building..But its not working

Try to check you resource folder(res/), it is containing error, Fix all error in res/ folder. then clean up your workspace. and build the project again, it will works.
R.java is automatically regenerated for you as soon as your res/ is corrected.

My answer is assuming that you are using Eclipse. Cleaning a project deletes its bin and gen folders and rebuild them again. Don't clean while having errors in the project as it won't build R.java on cleaning. It will show a lot of R errors in project as R.java is no longer present. But it will be showing the actual error in the console window. Fix it and R will build automatically.

First you check Your *.XML files if there is any error If error then first solve it.
Remove all import android.R from your activity
Run Project->Clean it remove all auto generated files
Build project using Project - Build Project it rebuild your project OR Checked Auto Build ON
Wait for a while it regenerate all files including R.java
If steel R.java is not generate then it is problems related to Project Build Target
Right click Project Go Properties->Android see in right section Project Build Target and see it match with your AndroidManifest.XML
Make change accordingly and repeat above steps
This one help you..

R.java was deleted after cleaning the project

I accidently deleted my R.java after cleaning the project (Project->Clean). Is there any way to restore or re-create the file?
I tried to build the project but R.java still missing from the project.

Here's a the things I ahve tried.
Rebuilding the project (failed)
Manually creating R.java and wait until the adt will generate the content (failed)
Did Project->clean another time (failed)
Deleted the gen folder and waited until adt will re-create it (failed)
The answer:
Created new project and copied the files that not auto generated (succeeded)

You have to build the project to be able to use the newly added resources.
Cleaning a project removes all auto-generated files. Building the project it should automatically create them. When you Clean a project, there's an option to start a build immediately after clean up.
Here's a few things you can try (did the same procedure after manually deleting the "gen" directory.
After you have deleted the gen directory, go to Project > Clean ...
You should have errors indicating that R cannot be resolved to a variable. Right click on your project from the Package Explorer and select Build Project. Be sure Build Automatically option is turned off (uncheck in Project > Build Automatically).
Errors regarding R should have now disappeared. Now, perform a Project Clean once again. All errors should be gone.
Let me know if this works for you.

Build the project again an do not worry, R.java is generated each time the project is built

I will automatically create by eclipse no need to create by us. just build the project i.e save the changes will automatically build it for u.

R.java file is automatically created when you build the workspace, so it should be generated again with the next cleaning of project, unless you have errors in java or xml files, so check if you have errors in your project and correct them first.

In the eclipse you have down to the clean project you have option Build Automatically try to enable it....

Just click Project > Build Project
When you build the project, you don't get R.java.
You should check external library. Just remove the external library and add external library.
Android projects get tangled easily.

Just Restart the Eclipse will solve this Issue as the workspace will be freshly Build ! go to
File -> Restart
Try this method by first right click on ur project folder -> Close Unrelated Projects!
Its the fastest way to avoid frustration by going it into Build,preferencen,properties,blah blah.....
Moreover, this technique always works when the R.java file is deleted and not restored back immediately !
Evenafter the problem persists then make a new project and add copy ur xml and java files to that project , delete the previous one . . . .

I had a similar problem: building the project, the R.java file was missing. I built the project, but there were errors in the resource XML file. Correct them, then rebuild. When there were no errors anymore, the R.java was recreated and contained all the R.id.xxx items I had inserted in the resource.

This recently happened to me (10 mins ago) for my Android project, and my solution was a mix of things I read in some answers here.
What I did to fix was:
revert to older version (I used Github)
R.java still missing so I deleted "gen" and "bin" folders
R.java was generated and errors disapeared
This was done using Eclipse Luna. Good luck.

Gradle Project Tab
I tried clicking all the stuff under Gradle Projects tab, and noticed a few small errors, example: I had a capital letter in the drawable folder. I ran anything that had to do with processing or updating or generating resources. final one I did was "processDebugResources"
missing R folder
I had also noticed the folder circled in the above image was missing, running "processDebugResources" seemed to have regenerated the folder, although the others I clicked under the Gradle Projects tab could have also helped

"R cannot be resolved" may have wrong build path or libraries import

I know this question has been many times but trust me I have checked all. Most of the question suggests to remove import android.R , remove any error in the xml file, checking name of the files (no capital letters) then rebuild and clean the project or restart eclipse. I have tried all but none solved the problem.
The problem occured when i cleaned all the projects. Now all the projects are showing that error. Since all the project were running perfectly before i cleaned projects, there is no possibility that all of the sudden the layouts or the file names of all the projects have error in them.
Also there is no file in gen folder. As far as i can understand there is something wrong with the build path or preferences can anyne point me in a correct direction? !

Make sure you installed the Android build tool form sdk manager
project right click properties-> Java BuildPath select Library and add android-support.jar the follow these step.
Go to Project->Properties->Java Build Path than select Order and export tab. Set android-support .jar library checked and up it into top of the list. And clean and rebuild..It works for most of the cases

Check the answer here and the thread here. Check if your layouts contain any errors (this has to be done manually or automatically only with Android Studio). Search for incorrectly closed tags like <string> - </string>.
EDIT (taken from this thread):
Cleaning a project removes all auto-generated files. Building the
project it should automatically create them. When you Clean a project,
there's an option to start a build immediately after clean up.
Here's a few things you can try (did the same procedure after manually
deleting the "gen" directory.
After you have deleted the gen directory, go to Project > Clean ...
You should have errors indicating that R cannot be resolved to a variable. Right click on your project from the Package Explorer and
select Build Project. Be sure Build Automatically option is turned off
(uncheck in Project > Build Automatically).
Errors regarding R should have now disappeared. Now, perform a Project Clean once again. All errors should be gone.

How to regenerate R.java after clean projet on eclipse?

I'm working on android 2.3.3 , when I clean my project on eclipse the generated class R.java is deleted , I tried to fix the projects properties by a right click and choosing Android tools , but it does not works.
How can I regenerate the R.java ?
Thank you

In Eclipse :
Select Help > check Updates...
Select the Installed Software tab.
Click Update...
If an update for ADT is available, select it and clickFinish.
Restart Eclipse.

If there are any errors in the layout or any resource files there will be no build happening and the R.java file will not be created.
Please solve the errors and then try to clean the project.

Everytime you clean the project and it rebuilds, it imports
import.android.R
so, delete this import and remove all errors from xml files. It will work.

Also if you tried to speed up eclipse and unchecked
Preferences - > General -> Startup and Shutdown - > Android Development Toolkit
check it back and restart eclipse, then R will generate automatically

R.java deleted automatically: Android

When I changed some design in .xml file, R.java file automatically deleted. How can I get back that file and what is the solution to resolve this problem, that in future this problem does not occure.

check all your errors in xml files structure (layouts, string etc...) even if sometimes they are not easy to spot.
My advice is to undo the latest things you've done until you find where the errors were and fix them.
Once they are all fixed the R file will be created again (maybe you need to clean your project: project -> clean)
In the future just try not to break the xml files and this won't occur again xD

You can also disable automatic build in your Eclipse IDE(Menu -> project- > Uncheck build automatically). This way the R file will be recreated only when you manually build the project and not when you save changes in an xml file.

Fix your errors and the R.java file will return...e.g when i added an image in my resources folder its name was in uppercase....when i changed it to lowercase,immediately after doing it my R.java file returned...its all due to errors...just fix them and it will return

I agree with #maid450.
I also have faced similar situations.
If your problem isn't resolved after all this, ultimate option is to create a new project, and copy files to it.

one solution is that Go to Eclipse project tab -> uncheck Build Automatically -> Clean the project.Make sure that there is no error in your project also don't try to edit the R.java file one it will created. Then manually build the project. you will get the r.java file.

The best solution for Mac/Eclipse user is to go to the SDK Manager and re-install the Android SDK Build-tools, and then restart Eclipse.
For some reason after performing a Clean action on a project the R.java file for all projects happens to be deleted from the system.

Clean the project.
Menu [Project] -> [Clean...] -> Select you project -> [OK]
Project will rebuild automatically, if not, chek
Menu [Project] ->[Build Automatically]

The R file deleted automatically when I changed my activity_main.xml in Android Studio.
What I did was copy the R java file from another project and paste it into the project in which it got deleted.
Hope it helps. :).
Location for R file.
Project/app/build/generated/source/r/debug/com.android.'projectname'/R.java
Where is the R.java file in Android Studio?