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Eclipse giving error, missing R.java file after recent update

I have updated my SDK and ADT to the latest version, I have also update the Eclipse to Kepler the latest one after Juno.
My ADT version is 22.0. After this update when I create a new project, I'm getting error, stating R cannot be resolved to a variable. I have imported import android.R;, but it is showing as unused import stating Don't include android.R here; use a fully qualified name for each usage instead.
Same thing is happening with Mac OS also with the latest update. I have tried renaming activity_main.xml to other name, but still my R.java is not generated.
Tried all the things which are possible. Cleaned the project, build the whole workspace. Nothing helping.
I think ADT or Eclipse compatibility is having problem after the update.
I have updated my whole SDK, here is the screenshot, but same problem is there.

After updating to SDK Tools to rev. 22 for the first time, you may need to relaunch Android SDK Manager again and install a new item: Android SDK Build-tools.
After installing this, clean your projects and rebuild.

Yesterday, I made an update with sdk manager, and I had the same problem as you. I fixed the issue: I have updated another time the android sdk (with the sdk manager tool), then I check update from eclipse for install the updated ADT plugin and I rebuid my project. "Android sdk Build-tools" from Android sdk manager is now rev 17 and now it is OK. I think the issue is from adt plugin from eclipse

import android.R - remove this statement from all your classes and then do a clean your R file will be generated. if this did not work then check all your xml files for any errors and then do a clean. These 2 are the most common reasons for R file to go missing

Changes in your Build target also can effect R.java in Eclipse so
Right Click Project >> Properties >> Android >> Select Latest(usually) Android API Platform >> Click OK
Hope this is helpful.

Follow These steps...
Right Click Your Project.
Select Properties->Android Check Project Build Target and API Level.
Again come back and open Android Sdk Manager Chekc the Tools and make sure you are installed Curresponding Android SDK Build Tools.
Eg : IF you selected api level 17 in properties you should install Android SDK Build Tools 17..

Try this:
make a backup of your projects on desktop
close eclipse
delete your workspace
restart eclipse and import your projects again.

I had same problem.. I solved by doing the following:
check all xml files and drawable files if there are any CAPITAL LETTERS in file name, if you have then change it to lower case, if you are using selector xml files then check the other files you are linking in those files..all should be lower case.
Go to java files which show error and remove IMPORT R.java file from imports list.
Go to Projects>>Clean.
This should fix the problem. This is how i fixed :)

My issue was that I had android:orientation misspelled in my activity_main.xml file and I was getting this error. I fixed the spelling and problem went away! So make sure activity_main.xml doesn't have any errors in it.

Sometimes when you extract your file it miss some part so better when its extracting make sure all file are extracting properly and then run eclipse after that run a simple file and install plugin of avd
it helped in my case

if the problem persists then try closing the other projects by
right click -> close Unrelated projects !
this worked in my case

For eclipse users:
Comment the lines including R.*
Clean and build.
R.java will be generated and then uncomment the R.* and rebuild.

the best solution for r.java missing for linux...
R.java is self generated in gen folder.. so better dont edit or create manually by urself ..
-open terminal(alt + ctrl + t)
-change directory to skd->tools
-then provide executive attribute to all executable file by(sudo chmod +x filename)
-do the same for files in sdk->platform tools .. (ie sudo chmod +x filename) ..
-----every executable file sud b provided with +x attribute...

just delete gen folder all of your error will be cleared

Proven successful method, check the file (AndroidManifest.xml) and delete all comments in it, and make sure there are no errors in this file, I tried and did work with me.

Eclipse Upgrade Not Working

My Eclipse out of the blue stopped building my Android so I removed the old version and have installed Indigo. When I try to import an Android project in I get this error:
Errors occurred during the build.
Errors running builder 'Android Resource Manager' on project 'ACCUWX_HoneyComb'.
java.lang.NullPointerException
Errors running builder 'Android Pre Compiler' on project 'ACCUWX_HoneyComb'.
java.lang.NullPointerException
Errors running builder 'Java Builder' on project 'ACCUWX_HoneyComb'.
java.lang.NullPointerException
Please help!

Try removing the .metadata folder from your workspace. This holds all your configurations, even after a new install. I think if you just delete this folder, assuming everything is in place, you should be up and running again.

The 21.0.1 version of the Eclipse ADT tools has a bug that prevents a project building if you have any files without extensions in them. This is a particular problem for users (like me) using subversion which has extenion-less files.
The solution is to install the 21.1 preview version of the ADT tools and SDK manager from Google. Clear instructions can be found here and you can read all the background add your voice to the angry mob of developers here.

This happened to me today with ADT v21.0.1-543035 and it turned out to be the .svn directories throughout the directory structure. See http://code.google.com/p/android/issues/detail?id=42051
Worked around the issue by upgrading svn client and working copy to 1.7.

For me, the source of the NullPointerException problem was a host-side Junit test project that references (and tests) code from an Android project. It didn't have a project.properties file. It's not an Android project, but for some reason the newer version of the SDK somehow expects the file there. To fix the problem, I just copied a project.properties file from an Android project to the host unit test project.

I had something similar. The problem was created by having some files without extension inside the /src folder.

In my case, a branch tool, changed the encode of the file project.properties, I changed the encode to Windows-1265 and the problem was solved.

I had the same issue and fixed it by following comment number 6 in this page:
Issue 42051: Subversion folder causes NPE in PreCompilerBuilder
Let me quote the comment:
Solved it by installing subversion support packages for eclipse:
http://gan.so/VgYT
It's still a bug but...

same problem here, I closed Eclipse, manually removed any files in folder gen for the project, started Eclipse again, and made a build.

For also me, the source of the NullPointerException problem was a host-side Junit test project that references (and tests) code from an Android project. It didn't have a project.properties file. I added it and problem got fixed.

I found the solution on this website(https://code.google.com/p/android/issues/detail?id=68755)
So basically, what we should do is :
Bring up $ADT_DIR/eclipse/Eclipse.app/Contents/MacOS/eclipse.ini in an editor. Before the -vmargs line, insert these two lines:
-vm
/System/Library/Frameworks/JavaVM.framework/Versions/1.6/Commands/java
you can find the eclipse.ini following this
(On a Mac OS X system, you can find eclipse.ini by right-clicking (or Ctrl+click) on the Eclipse executable in Finder, choose Show Package Contents, and then locate eclipse.ini in the MacOS folder under Contents)

Upgrades did not work for me (on Linux), so I just installed IntelliJ Idea (build 123.155). Had to modify idea.sh to set JDK_HOME=/usr/lib/jvm/jdk1.7.0 (the Oracle JDK) and to select [menu] -- Run -- Run... -- Edit Configurations... -- Target Device -- USB device to make it work with the real device.

The project was not built since its build path is incomplete

Every time I try to import a project downloaded from googlecode into Eclipse but I get some errors:
The project was not built since its build path is incomplete. Cannot
find the class file for java.lang.Object. Fix the build path then try
building this project
Unable to resolve target 'android-10' (this changes from 1 to 15)
I've already checked the other answers on the site but no solution worked.
In
Properties -> Java Build Path -> Libraries
there's 1 item:
Unable to get system libraries for the project

Right click on project -> Properties -> Java Build Path (From Left List) -> Libraries (Tab) -> Add Library (Button on right) -> JRE System Library -> Next -> Workspace default JRE -> Finish
This should solve at least one of your errors. Any others might require you to add further libraries.

Close eclipse and re-open worked for me. You may have to do this two or three times. Each time give it a minute for the auto build startup process (check bottom right hand corner) to complete, as these errors often disappear at this time.
Or try to clean the affected projects.
'Turn it off and on again'

It seems that you lack JDK (java.lang.Object comes from there )
The problem is that you used the same Android API on different PC. Eclipse is lost with path names that are differents but with same API.
To solve it, first re-select Android API version (set to another one and valid, then restore the on you want and validate it -> it will force Eclipse to reload API).
Then go into project->properties-> java build path. Then remove "Unable to get system library for the project" then "Add library" and select "Android Classpath container".

Initially I was trying to import an android project from github and encountered the above problem
cannot configure build path
unable to get system libraries
Package Explorer -> Right click the project -> “Properties” ->
"Android" -> "Project Build Target" = 2.3.3
Note: Also try Clean (On Windows: Project -> Clean) then Refresh (F5) at random. There's a good chance this will magically solve all your problems.
courtesy: KYLE CLEGG
reference link

None of this worked for me. I created a new workspace for the projects. That worked for me! Switching to a new workspace usually miraculously solves a lot of these configuration problems. Simply create a new folder where you would want your new workspace to be and then use 'import project from existing code'.

Goto eclipse → Preferences → Java → Build path.
Do you see a JRE_LIB configured there? If not, add JRE_LIB from JDK/jre lib location. These can be overridden per project. It seems your eclipse isn't aware of Java libraries.

I have seen such errors in past while importing projects in eclipse. The solution to that is to go to properties->Android and select project build target appropriately (Android x.x.x or Google APIs)

Was struggling with this while trying to load the Vuforia Sample App for way too long today. The solution that finally got my project to build was:
1) Window->Android SDK Manager and Install the latest updates
2) Project->Build Path->Configure Build Path->Android and under Project Build Target mark Android 4.4.2 and click OK
3) Clean, Build and Run
I hope this solves somebody else's issue as well, Eclipse is frustrating as F$##!!!

I encountered with the similar problem.....
Make sure that
You create your project within your workspace. If your project is not in the default workspace where .metadata folder within which other plugin folders, and etc. will be present, then it will ask you to configure build path as the project is not build because of incomplete build path.
If the first step is clear, then go for this.....
Right click on your project -> build path -> configure build path -> libraries -> Add libraries -> JRE system libraries -> Apply and close.

I've had similar problem. Exact same error, but in Ubuntu after I worked on project in dropbox folder from Windows.
I've just added android.jar to project. Somehow it disappeared from build path.

For me this problem was related to OpenJDK 6 on Ubuntu.
Update your JRE or install Sun's proprietary JRE instead and restart Eclipse.

I know this is too late. but I am also facing this issue and I fix this by following below steps.
This issue is occurred only if the project shared between different machines.
For me I found java JDK is the problem.
My colleague used mac system and using jdk 1.7. but in my system I used jdk 1.6.
I guess that may be the issue. So I select project and open properties and change my jdk to 1.7
Change target=Google Inc.:Google APIs:19
Clean & Build
Finally issue is fixed. I think this is because of If you build your project with higher JDK version thereafter you should build with same version.
NOTE : we are not facing this issue before until my colleague build with JDK 1.7. After he started to using JDK 1.7 only this issue occur.
Hope it will work for some one. And no need for install new eclipse.

I had my "Build Automatically" turned off in "Project". I turned it off, because the Eclipse was not loading the projects correctly, for various unknown reasons. Turning this on, solved my problem.

if the project is not very big, you can copy the packages and paste it into a new project, you won't see the errors in the new project.

I was having target-18 in my project.properties. But I wasn't having android-18 sdk. So I changed 18 to some other version which I had in my SDK manager, and it fixed the issue.

You just exit eclipse once or twice to reload. It works for me.

Steve's answer does help for some projects, but still, for some projects, it remains the same. I guess that projects were previously build-in early JDK 1.5 (in my case). But I found a workaround for them:
Find the class that causes the problem (Keep expanding the project in the Package Explorer).
Copy the class's contents after the import block.
Delete the whole class.
Right Click on the project then Android Tools >> Fix Project Properties
Create a class with the same name under the same package the deleted class was before. (If the project is imported and the deleted class was an Activity/Service/Provider/Reciever, I guess the class is already included in the AndroidManifest.xml).
Paste the content of the class and import packages.
Clean the project.

I had to delete R.java in the gen folder, then do a clean build. This solved my issue.

Gen folder is empty for Android project

I'm starting to learn Android in Eclipse. But every time I try to create a project the gen folder is empty. So I don't get the R file(or whatever else is in that folder, if anything). Clean does NOT work. There was never an R to begin with. Do I need to download something to make it generate it?

had the same problem. Check in the Android sdk manager, tools and check if you have installed android sdk build-tools. had the same problem because i hadn't installed it.

I had this problem because I had two projects in the same folder and one was the library of the other. Then Eclipse built the projects in the wrong order. What I did to fix this was close the non-library project and then open it again (after the built of the library project), which made it work.

None of the solutions posted here worked for me: Clean, changing options, build errors, etc. The problem was caused by importing the Android project as a normal project, i.e. using:
Import > General > Existing Projects Into Workspace
instead of using
Import > Android > Existing Android Code Into Workspace

One of those
Getting rid of 'import android.R' line.
Cleaning the project and then building it again.
Closing project and then opening it again.
may help.

May be your problem was related to incorrect target build settings.For example if you use an element in your layout that is available in greater Android targets.You can see more details here.

STRUGGLING FROM THIS BUG FROM LAST TWO DAYS. FINALLY SOLVED IT :)
The best way to get rid of this is to go to WINDOWS option on the tool bar -> ANDROID SDK MANAGER -> and tick TOOLS option on the top tools bar (i.e. all all android sdk tools , android sdk platform tools , android sdk build-tools.) and install.
After updating all these too latest versions , go to HELP and hit CHECK FOR UPDATES and install all these new version plugins.
Last step is to go to PROJECT option in the tool bar and uncheck the BUILT AUTOMATICALLY option and go to CLEAN and perform clean on required or on all projects.
I know this method might consume some of your net mb's but will definitely solve your problem.
E.njoy...:)

I ran into the same problem. I had incorrectly set the path of the Android SDK. Setting the path in Windows -> Preferences -> Android did the trick for me.

I had the same problem. Just add these two line in your project.properties file
target=android-19
android.library.reference.1=../appcompat_v7

I happened to have the same problem, solved by "Right click on your project and then click Build Project".

Try this,
Right click your project
Select properties.
Select Java Build Path
Click add Folder
Select the gen folder
Click OK.

Could not find ****.apk + android

Whenever i am trying to run my project, i am getting this error in the console.
"Could not find **.apk"
Operating system: windows XP
IDE: Eclipse SDK
Version: 3.4.2
Build id: M20090211-1700
Android: 1.6
ADT: ADT 10.0.0
FYI: it is only happening with a single project, other projects are running fine..

I think this can happen when you rename the library project out from underneath the dependent project. Eclipse is reasonably good about about updating dependencies in most cases but this one seems fragile.
First try removing and then re-adding your library in Project > Properties > Android > Library.
If that doesn't work try cleaning your projects, exiting Eclipse, and opening the ".classpath" file in your project's root directory. If you see a line that references your library project under a previous name, just delete it, save the file, and relaunch Eclipse. Build the library project and then your dependent one. You may need to re-add the library like I mentioned above. This is what worked for me at least.
Edit note: I also found some stale references in my .project files. They didn't seem to be causing any problems but I removed them too. If you do that, be sure to search for the old name in that file as there was a whole "link" section near the bottom that also referenced it.

Make sure after updating your android sdk sdk build tools are updated properly.
You can check it by Open sdk manager -"Android Sdk Build Tools" status must be installed.
if the status is not installed then install Android Sdk Build Tools for the same.

restart your eclipse and try again
check this it might be helpful to you

Make sure your project imported the Android 1.6 library correctly. That is, under your project, you should see 'Android 1.6', which expands and displays 'android.jar'.
If it says Referenced Libraries > android.jar, you will need to fix this by manually altering the .classpath for the project.
Open .classpath for the project and type the following:
The important line is the 3rd classpathentry, which is the actual link to the Android SDK libraries.
source

clean your project and check . eclipse is not building apk file.
check this thread. It might help you.
http://groups.google.com/group/android-developers/browse_thread/thread/2c3e45540b915945/f06e10bcda3ad68b?lnk=raot&pli=1

Run eclipse as administrator and then import your project

Update Android SDK, is what did it for me.
I was building a game with the LibGdx Framework and got the same error. I tried several solutions from various posts at stackoverflow and others.
Found help in a post at the LibGdx Forum:
http://www.badlogicgames.com/wordpress/?p=3010 Posted by Mario, on May 18, 2013
Just updated to ADT 22, so should you. However, the process wasn’t all that smooth. What you need to do:
Update the ADT plugin in Eclipse (Help -> Check for Updates)
Open the Android SDK Manager, either from within Eclipse, or from
your Android SDK folder
Fetch all the updates
Fetch all the updates again
Fetch the updates one more time…
The end result should be an updated ADT plugin, as well as up to date SDK packages. Make sure you have all three of the ones in the following image, with the exact version numbers.
I needed to update them only once and from there on it worked.
Even if this post is outdated I figured I'll share this, because I lost a day finding nothing.

I experienced that problem, too, when I created an android project that was using an android library. Obviously I didn't know how to incorporate a library into an application the right way. I wrongly used project dependencies (Java Build Path/projects) or adding a library (Java Build Path/Libraries). While all I had to do was go to the Android tab and import my android library by means of the add button from the Library section.

I am using PhoneGap and I checked several solutions about configuration (properties, build path). However, my problem was that I tried to run everything with the default setup for Eclipse. Then, I solved it going to the SDK manager to install: Android SDK Build-tools, and it worked.

Mine was caused by this problem (incompatibility between ADT and SDK), and was fixed thus:
Eclipse > Help
Install New Software
Add 'https://dl-ssl.google.com/android/eclipse/' to 'Work With'
section and press enter
After developer tools appears on the list, check it and click Next
Restart eclipse once download is finished

Make sure put correct SDK Location (I have 2 instances of SDK and update wrong once).