R cannot be resolved - Android error

Question

I just downloaded and installed the new Android SDK  I wanted to create a simple application to test drive it   The wizard created this code   package eu mauriziopz gps   import android app Activity  import android os Bundle   public class ggps extends Activity           Called when the activity is first created          Override     public void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout main             but Eclipse gives me the error     R cannot be resolved   on line  setContentView R layout main     Why   PS  I do have an XML file named main xml under res layout

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I just had this problem for the millionth time and realized what was causing it  I created an XML file with uppercase letters in the name  All your XML filenames in  res must match  a-z0-9

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This works   Step 1    Download https   www dropbox com s 7nwlrg05ke05tat GalleryImageview zip  Step 2    Load eclipse and load the project   Run and Test will work on the fly  Step 3    Update here if anything is wrong   Enjoy  Happy coding

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Right click on your project and click Refresh Or hit F5

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I had the same issue  but couldn t find out what xml file caused the error   Thanks to this post I installed build tools 18 1 1 instead of 19 and it showed me the defective file  It seems that version 19 doesn t show the actual error   Hope it helps someone  -

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R is auto generated resource in android project some times it happens don t exactly know why but have you try build automatically option from project     remove other import of R file of other project or android r    always remember if you always face problem with auto generate id or auto     deleting R file you can generate static id like string file and use that with  id instead of   id

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After tracking down this problem as well  I found this note in the Android documentation   http   source android com source using-eclipse html      Note  Eclipse sometimes likes to add an  import android R  statement at the   top of your files that use resources    especially when you ask Eclipse to   sort or otherwise manage imports  This   will cause your make to break  Look   out for these erroneous import   statements and delete them     While going through the Android sample tutorials  I would often use the Ctrl   Shift   O command to  Organize Imports  and generate any missing import statements  Sometimes this would generate the incorrect import statement which would hide the R java class that is automatically generated when you build

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I faced the same problem after putting some graphics in the drawable folder  There was some error and when I tried to clean  the R java file was not there   So I carefully checked and found that there was some files with uppercase file names and some files are having the same name but different file extensions  I renamed those files and had a unique name in lowercase for every file  Remember Android cares about the name of the file  not the extension   Maybe this can help to you or other readers

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Simplest solution - Sometimes you just need to save the XML file you were working on to get the autogenerator to kick in     Save the file  e g  main xml  then delete the R java file and see if the regenerated R java resolves the R resolve problem

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Every time I come to this error and always been landed on SO  and end of the day the reason is same    So Please Keep in mind always this small note  I found most of the time reason is - error in  XML layout     If your XML isn t correct  then the R file is not generated after a   build

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This worked for me   I had no  import android R  in the brand new project the eclipse wizard created  the default xml layout file was lower case as well   Problem was eclipse was not generating R java  No amount of cleaning restarting was having any effect   I commented the setContentView and getMenuInflator calls and the make succeeded after which Eclipse generated R java   Once R java was generated  I was able to uncomment setContentView and getMenuInflator

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Make sure that all your resources files doesn   t have upper case extension  I found out that I saved some images with upper case extension  PNG  I changed it to  png and everything got back to normal

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restart your computer  Nothing helped me except this way

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If you work with eclipse  Sometimes eclipse supresses the error messages in the ressource files   Solution  Save a temporary ressource that has no errors in the layout folder   Build the project new   Then eclipse shows the correct error in the ressource file   Delete the temporary ressource

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There are several reasons of R can t be resolved    Most of time this error occur for XML file fault  This error can be solved by Clean and rebuild your project  also you can restart your android studio  Sometime If you codeing some wrong thingin AndroidManifest  this error can be occur so Please check this  If your resources contain the same name or they have invalid characters  this error can be occur    If you already check those and yet you are facing with same problem then go ahead     This error can be occurs when Android Studio fails to generate the R java file correctly  so you have to follow those steps   Step 1  Safely delete the build folder from app directory  Step 2  In Android Studio  File - gt  Invalidate Caches   Restart Step 3  Build - gt  Clean Project Then Build - gt  Rebuild Project    so build folder will be regenerated and hope so error is gone     If Error still found then maybe you have performed refactoring the package name previously  This case you can press ALT   ENTER together for import the R

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And another thing which may cause this problem   I installed the new ADT  v  22   It stopped creating gen folder which includes R java  The solution was to also install new Android SDK Build Tools from Android SDK Manager   Solution found here

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just clean and rebuilt your project it sometimes help

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R is an automatically generated class that holds the constants used to identify your resources   If you don t have an R java file  it would be gen eu mauriziopz gps R java in Eclipse with the 1 5 SDK  I would recommend closing and reopening your project or going to Project   Build all  and selecting  Build Automatically  while there as recommended by Josef    If that doesn t work than try making a new project  if the problem is recreated than post here again and we ll go into more detail

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Yet another reason this might happen  Tonight  I met the dreaded error  and eventually discovered an errant mouse drag apparently moved one of my own packages  classes into the hierarchy of another  There is truly no end to the number of ways you can screw yourself in the Eclipse environment

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My solution  on Eclipse Juno  was to click on  Fix Project Properities  by    Click right mouse button on project  Choose Android Tools menu Click on Fix Project Properities   ps  First check if R library is not implemented and if all files in res  folder are ok

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One shoudn t try to import android R  Try to fix all errors that appear in XML files  including the manifest file  When all errors are cleared  R java will reappear

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just clean and rebuilt your project it sometimes help  Make sure that there is no error in your res drawable folder in android While naming images in this folder don t give numbers and capital letters

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Import R class with your package name  Do not import android R class

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Each time I had a problem with R not been generated  or even disappeared  this was due to some problem in the XML layout file that prevented the application from being built

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Of the many possible problems that could cause this  this is what fixed it for me     Right click on project -  properties -  Java Build path-  source     Then add the gen and src folders  For some reason  Android wanted me to only have the overall folder

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Just Restart Your Project     File  invalidate caches  Restart   Note    Android automatically creates a  R file not need to import Import android R    lt  lt  R java file auto created by android Studio Android studio has lots of caches hold and that s why some time it s occurred

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My R file disappeared and wouldn t generate - the console reported this    2010-09-22 16 19 40 - myproject  res drawable-ldpi downloadNow png  Invalid file name  must contain only  a-z0-9     So it turned out that resource names cannot have capital letters - confirm that they are all small letters and contain   and   only

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Whenever you get      R cannot be resolved   then check for the  res directory and there must be some file that have some error in it and that is preventing the application from being built  For example  it may be a layout file or it may be due to some missing resource is  but you already defined it in the XML file   If you have any additional  even unused     or unreferenced     images in a folder like res drawables-mdpi which do not comply to the file naming conventions  may contain only  a-z0-9      the R java class might not generate  causing the chain of events all the other posts referred to  Hope it helps

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first of all look at your gen file if it contains your package name and R java or no  if it was empty maybe you don t have permission to create new files so exit eclipse than right click  run as administrator and clean your project and everything will be correct   otherwise you should have an error in your XML file maybe or check the other answers

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This error cropped up on my x64 Linux Mint installation  It turned out that the result was a failure in the ADB binary  because the ia32-libs package was not installed  Simply running apt-get install ia32-libs and relaunching Eclipse fixed the error   If your x64 distro does not have ia32-libs  you ll have to go Multiarch   Check  4 and  5 on this post  http   crunchbang org forums viewtopic php pid 277883 p277883  Hope this helps someone

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Sometimes it helps when you manually create R java file just simple empty R java

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If you are on a Mac  check if a  DS Store has been added to a directory in  res  ls -al on the Terminal command line   Remove it and refresh rebuild

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Remove main out xml  I m new to this and don t yet know what this file is used for  but removing it cleared the problem

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I changed android versionName in file AndroidManifest xml from 1 0 to 1 1  That regenerated my R java file  and I m a happy camper  I hope this might help somebody

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reason R java might not get auto generated is if you have directories like            res drawable-hdpi   res drawable-mdpi   res drawable-ldpi   image name should be in a proper way   Check the Image Name     and check the  and layout any xml    and string xml

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It is worth checking in AndroidManifest xml  The attribute package has the correct value   That is    lt manifest xmlns android  http   schemas android com apk res android     package  your correct package name           After you change that  the R java will be re-generated

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I solved it for myself with Window- Preferences- Android and SDK Location  path to adt sdk e g  C  adt sdk

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Check the XML file names   Be sure that they re all in lowercase   Also make sure that any image resource names are also all in LOWER CASE  I had a capital letter in the name of my jpg file  and it caused the R unresolved error right across my project

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Press Alt enter and Import  or  Ctrl F9  and solved

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Yet another reason R java might not get autogenerated is if you have directories like res drawable-hdpi  res drawable-mdpi  or res drawable-ldpi     1 6  seems to be OK with these directories  but 1 5 doesn t want them  When I removed those directories  R java started autogenerating for me again

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Wow  I resolved my R issue by tracking down all possible errors in all XML files and related resources  I know that is a handful of layers  but simply you must    Make sure any referenced resource image is actually there Everybody already mentioned so much that this is just echo     Remove all Eclipse injected R   imports if need be  I like to restart Eclipse when I do the above  Make sure all XML files are properly structured  Like  just do your stuff  Hahaha Go through as many lines as you can  Get in the habit of hitting Ctrl   Shift   S often to get compiler results quickly changed    Hahah  Sure it is nice to get the R Cannot be resolved fixed though

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To resolve R   Make your all XML file correct   and then Clean Project in Build menu  This is the simplest way to do it  Hope it hepls

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Close all files  clean project  restart Eclipse

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Make sure if you re looking for R drawable   that the file exists in your drawable  folders

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Unfortunately none of the existing questions helped  Since my problem seems platform specific  this may only work if you are on Ubuntu 64 Bit  I am currently using Ubuntu 12   At first I did not see the  Problems  Window  which already hinted a solution  that on 64 Bit Environment you need the 32 Bit libs  which may be missing      sudo apt-get install ia32-libs   I installed the package and rebuild my project  which fixed the issue for me

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Change build target from 1 5 or 1 6 to 2 2  API version 8   and check if you have the   character in string xml  If yes  replace with

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Recently  I faced a similar situation with R that could not be resolved    Project -  Clean  it usually works  but this time it didn t   I tried to remove the gen  folder  which automatically gets built  - nope  Dummy modifying a file  Nope again  By now I was going grey  I checked in the AndroidManifest xml file if appName was present  It was - checked  Looked again at my res  folder      And this is where it gets weird    It gives an error  in some but not all cases                                I added the formatted  false  flag    lt resources gt       lt string name  blablah  formatted  false  gt       lt  string gt   lt  resources gt    Bingo

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In my case I was trying to convert my project into Maven  After while and thousands of random errors which were saying NOTHING  I tried to undo all of operations  What I didn t notice  project file was changed and it wasn t visible inside Eclipse    Only reverting  project file to before-maven version helped me fixing this error

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My problem was that I left out the   mark from the strings in strings xml e g    lt string name dialog grl     It did not appear to me even when the graphical layout of my  xml file could not show the strings  After a project clean all files got messed up

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Close all files  clean project  restart Eclipse    or   R is an automatically generated class that holds the constants used to identify your resources  If you don t have an R java file  it would be gen eu mauriziopz gps R java in Eclipse with the 1 5 SDK  I would recommend closing and reopening your project or going to Project   Build all  and selecting  Build Automatically  while there as recommended by Josef   If that doesn t work than try making a new project

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You may need to update install SDK tools  Relaunch Android SDK Manager again and install a new item  Android SDK Build-tools one by one delete fix which one work for you

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I think the problem is in layout xml  file or in import statement   Be sure that you have not imported R android   instead of import R YOUR PACKAGE NAME    It will work fine

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For me it was due to using  private  android drawables    2015-11-26 18 59 48 - MyAndroidApp    Users myname git MyAndroidApp res menu drawer view xml 24   error  Error  Resource is not public   at  icon  with value    android drawable ic menu home      The interesting thing is that this errors didn t show up in the Console until I removed the reference to the file using the icons  ugh     android entries   menu drawer view    Now the solution was quite obvious  copying the icons into my project  res drawable-XXXX   and switching to local references    drawable ic menu home   Hope this helps

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Install all Android SDK Build-tools and remove import android R in your Activity class  After click Project -  Clean  import android R

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There are two ways that R will an  error  1  Problem with your layout file ie xml file  2  If you update adt then the R problem will occure     - you have to check properties for the project    - goto- Properties - Java Build Path -  Order and Export and check for all the lib    It will solve the problem

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For me it was because of wrong java compiler version  Project Properities -  Java Compiler  enable  Enable project specific settings  and choose your  compiler compliance level

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Some answers suggest restarting the computer  I have found that restarting the adb server is enough -- this is particularly true if you ve just updated the Android SDK   Restart adb via a linux shell     cd  ANDROID SDK platform-tools     adb kill-server     adb start-server   You may need to restart Eclipse so it can reconnect to the restarted adb server  You may need to do a clean build if Eclipse doesn t compile projects automatically

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Check with the class files imports above and make sure that there is no import of android R  if it has then remove it and then press Ctrl   Shift    o and select the packagename R import not the other one

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my project have include a r java at the beginning  R layout main work good But after adding some code it doesn t work and the error is R layout main can t resolved what s the problem    Look at your imports  Chances are that the line   import android R    will be there  If that s the case  remove it  so that your project will resolve R not with the default Android Resources class  but with the one auto-generated from your  res  folder

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This could be an issue caused by manually renaming the package in the AndroidManifest xml  An alternative is to use the built in tool to rename the package  this will take care of most of the problems avoiding the R not found issue   Right Click on the project Click on Android Tools Click on Rename Application Project Enter the new package name   Then a pop-up will appear asking for changes to be applied  including the R workaround   Source  Rename package name in android

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From the many answers that were offered here  what helped me is to change the order at the  Order and Export  at the java build path   1 click on you project -  project properties  2 Java Build Path  3 Order and Export  Change the order of the Build class path to be  1  your-package-name  src  2 Android  version number   3 Android Dependencies   4  your-package-name  gen

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Another way this can occur is if you start a new project from one of the samples   When you later decide to change the package name from com example android foo to your own domain  you will need to modify several values in the manifest and in individual  java files    If you re in Eclipse  find the package statement for the  java file and choose QuickFix  There may be several choices there  but the one you want is the one that indicates to  Move  foo java  to package  com youdomain android yourapp    Save the file and it may autobuild or do as others have suggested and try  Project- Clean

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Same thing happen to me   and i passed a day to fix this  really this is a stupid error  i am just shearing my experience  may be it would helpful to you   First look carefully when you type this setContentView R layout activity to do list   hear your starting point R l then eclipse should open a suggestion for you look like this  you import the second one not layout-android R   the second one is created in your project hear com example gridtest is the project package name   then focus your imported section in your code   ok look this import com example gridtest R  its important   If you already import this android R then remove it  Thank you hope it works     you don t need to do this always but if you face this kinda problem then do this  hope it would help

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If cleaning the project doesn t work and if there is no problem with xml files If it is a new project   Then go to Androidmanifest xml edit it and add some spaces between the lines  save it  Now clean the project  error will vanish   This happens because of stale R java file  When we edit android manifest file R java is created again

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In my case this error was because i imported a image to the folder  res  and the image had a invalid name  Can t believe that i spend almost a hour with this problem until i realized that the image had a invalid name

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The real question is how to prevent the import android R  from returning   Window -  Prefs -  Java -  Editor -  Save Actions  Uncheck  Organize Imports     That will do it

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I was facing the same problem  I googled and tried suggestions I found but none of them worked for me   I changed my workspace and it worked  but before changing your workspace try other workarounds you have  Any one of them might work for you

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R is a generated class  If you are using the Android Development Tools  ADT  it is generated whenever the project is built  You may have  Build Automatically  turned off

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When you have just opened your project   it takes a while for android studio to load things up  It happens a lot with me  I just sit back and watch a youtube video for 5 minutes while it is done loading   By then the cant resolve symbol R is gone   -   If you have checked and re-checked everything mentioned above  made sure that the project has completed building  I d suggest you to patiently wait    If not clean and rebuild the project

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Along with the great suggestions in the previous answers  make sure your Android target is set    Right-click on your project Choose Properties  Choose Android in the left menu  Tick a box next to the appropriate Project Build Target  Click Apply and OK   Edit  A year later I found another cause   I had a  jpg image in my drawable folder with the same name as a  png image   Referencing this image in my code must have confused the program and it gave the  R cannot be resolved  error

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Check the content of your XML file  If layout width or layout height contain the match parent element  then change it to fill parent  It solved the problem for me

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I had this problem as well  It turned out that I had inadvertently deleted the  app name  string resource from the strings xml file  which was causing a silent error  Once I added it back  the R class was generated successfully and everything was back up and running

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I have got this same problem today  I ve tried to perform all sdk update using SDK manager   After finishing and restarting IDE problem has been resolved

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To resolve this issue please go to java Build path- order and Export and select all checkbox and select ok and then clean and build project and import your package name R file Ex com demo R   It works

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I had the same problem  In my case had to do with the layout XML file names  I had some of the file names with uppercase letters in them   screenQS xml - didn t work   screenqs xml - worked

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Just go to Android Top menu list  click on Build Menu  in under Build click on Rebuild Project

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i tried most method above   but not work my case  finally i found out the adb lost  for mac os   go to android sdk directory  type    adb start-server

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I tried most of the options on this thread  and many others  and nothing worked for me  Finally this one worked so I thought to share it with everyone     I have multiple versions of Eclipse IDE on my machine  because I also work on non Android related projects   Accidentally I created my Android project using a workspace that was being used by another  non-Android  version of Eclipse  Due to this I guess something weird was going on and my R java was never getting generated    To fix this  all I did is created a new workspace and magically R java started getting generated and everything went smoothly     So while you are trying all other options  give this one a shot too  And hope it ll work for you

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Check that the library projects that you ve imported into the app are all open   And for some reason  if you haven t added anything to the activity  like onCreate    it won t understand what R is

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First check is there any error in any xml layout or not  if then resolve it first   Otherwise remove junit dependency from project and rebuild the project

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When running x64 Linux you may be missing some x32 build libs  Ex for Debian make sure you have libc6-i386  amp  zlib1g packages installed

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What Will said was right     R is an automatically generated class that holds the constants used to identify your  resources  If you don t have an R java file  it would be gen eu mauriziopz gps R java in  Eclipse with the 1 5 SDK  I would recommend closing and reopening your project or going to  Project   Build all  and selecting  Build Automatically  while there as recommended by  Josef   If that doesn t work than try making a new project  if the problem is recreated than  post here again and we ll go into more detail    but I ve found out that there was another problem that was causing the first one  The tools in the SDK directory didn t have the permissions to be executed  so it was like the didn t exist for Eclipse  thus it didn t build the R java file   So modifying the permission and selecting  Build Automatically  solved the problem

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Often times this is because of the MinSDK version number you supplied when creating the project   Example   If you want 2 1 to be the minimum  Android 2 1 is actually API Level 7   You can see what I am talking about when you browse the SDK you downloaded and installed   Navigate to the place you installed the SDK to  C  android-sdk-windows for example  and open the folder named  platforms   You will see something like  android-7  listed as a folder  and if you open that there is a source properties file that  when opened with a text editor  will show you the corresponding platform version   When you create a project  and you must select a  Build Target  API  the last column in that list named  API Level  shows the number you are looking for when populating the MinSDK setting   This is probably one of the most common mistakes that results in the R java file not being created under Project   gen   packagename   R java

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I had the examples of Android 8 and was trying to use Android 7 SDK   When I closed the project and reopened the application folder and chose to use Android 8 SDK  it was able to find the R file   Hope this helps

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I had tried all of the above with no prevail  It turned out PhoneGap was causing a conflict with the Android SDK  After uninstalling PhoneGap  the Resources file started regenerating again  Another project  needed PhoneGap so I re-installed  and once again  the Android project  a different project  stopped auto-generating the R file - Build Automatically was checked  did the Clean  and restarted Eclipse - no dice  I removed PhoneGap and it was working once again  This was PhoneGap v 1 5 with the MDS 1 1 plugin for Eclipse

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This error can also be caused by adding an activity to a namespace that is different to the root namespace for your package   For example  if com example myapp is the root namespace for your package  you can then add an activity to the com example myapp activities namespace   This will produce the  R cannot be resolved  error   To fix the import the R in the default namespace in your activity should be   import com example myapp R

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Oh God I am Linux  ubuntu  this is how I resolved it     First thing the problem is permission problem I was not seeing any perission realted error but that was the problem  The tools were not have executable permission    So just a a quick fix If you know the exact file that need executable perission apply the ff command specifically to them      change to the dir you put your sdk  then     sudo chmod  x -R     After that goto project- gt clean- gt select your project- gt clean  That worked for me

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So I have run into this problem multiple times when switching build targets   Usually doing a Project    Clean worked for me   This last time  however  it did not   Finally I tried to open my default properties file  located under the root project folder   I received an error message stating that it was out of sync with the file system   I actually deleted it and copied a coworkers version which allowed eclipse to rebuild my R file   I will paste what it looks like below   It is named  default properties      This file is automatically generated by Android Tools    Do not modify this file -- YOUR CHANGES WILL BE ERASED       This file must be checked in Version Control Systems       To customize properties used by the Ant build system use     build properties   and override values to adapt the script to your   project structure     Indicates whether an apk should be generated for each density  split density false   Project target  target android-3

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In my case  R java was not generating because there was a problem in AndroidManifest xml file wherein I had wrongly specified the name of an activity

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For me  I removed  import android R   and it fixed all my problems  What a nightmare

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a better and more promising solution   close Eclipse and open your Workspace directory  look for a folder named   metadata  and delete that folder  Open Eclipse    the Error should go away

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You may need to update SDK tools  Relaunch Android SDK Manager again and install a new item  Android SDK Build-tools

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1  First of all close all the file  2  Go to the Build -  Clean Project  3  Go to the Build -  Rebuild Project      This works for me

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It worked for me with Right Click Android Tools Fix project properties and some time aftr restarting Eclipse

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Solution   Project clean after Eclipse restart  They are auto generated  otherwise you are XML inner any component  like button  after Ctrl   Shift   O  It autogenerated the R file and then the error was solved

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Also  if you have extra files like  desktop ini  in your res folders that are added by the OS but are totally unnecessary  try deleting them  This apparently was one of the things blocking the generation of R java in an imported project of mine

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I would say  R can not be resolved  is something too general and can be misleading at times  I also had the same problem many times ago even when I first create a new project  which mean I did not mess with the code yet   Most of the time I just need to update my sdk manager  as some people have mentioned   But in my recent case  I found out that the path to my project file is too long  something like this E  R amp D ANDROID ANDROID BASIC Folder 1  Folder 2        Folder n MyProject   The folder names also contain spaces character  I thought it could be the case and indeed it s true  when I created a new project in another folder with shortest path possible  and none of the folders  names containing space character  it worked as normal

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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

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I followed the advice to install the platform build tools  Then The message   lt package gt  gen already exists but is not a source folder  Convert to a source folder or rename it    appeared in the console  So I followed the advice and set  gen  as a source folder  This fixed the issue

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Each time I had a problem with R not been generated  or even disappeared  this was due to some problem in the XML layout file that prevented the application from being built   R is a generated class  If you are using the Android Development Tools  ADT  it is generated whenever the project is built  You may have  Build Automatically  turned off

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R java is a file that the Android Eclipse plugins creates while building your application  R java is created under the  gen  directory  This file is generated from the information in the  res  directory  If you run select  Project  -   Clean     on the Eclipse menu  it will remove and then regenerate the R java file   The problem  R cannot be resolved  happens when you change your package name in the AndroidManifest xml file  It uses your Android package name to create a subdirectory under the  gen  directory where it stores the R java file   Eclipse may have problems executing clean  because it is confused about where the R java file is when you have changed the Android package name  You can either rename the subdirectory under gen to match your new package name  or you can change your package name back to the old name  Do the clean and then change the package name to the new name you want  This works best if you stop Eclipse from trying to build while you are changing the package name  Under the  Project  menu uncheck the option to  Build Automatically  and also when the  Clean     dialog asks if it should  Start a build immediately  uncheck the box so it doesn t try to build while you are changing the package name  After you have changed the name you can turn  Build Automatically  back on again   Note that if your AndroidManifest xml file package name does not match your Java package name  Eclipse will end up automatically adding an  import  lt your Android package name  R   line in all your  java files that have any references to R  If you change your AndroidManifest xml package name  sometimes Eclipse does not update all of these added imports  If that happens  use the Eclipse refactoring  ALT   Shift   R  to change the import statement in one of your Java files to your new AndroidManifest xml package name  It is best to do this while you have disabled  Build Automatically

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I had this problem many times and I found that some times  R wont resolve  accrue because    some bad named Resource have exist like  an image with name My imge png or some error in Resources like error in xml files or Error in defining Resource in your forms that won t exist    in these case you even can t import your own package R to your project  so Go to your resource folder and search for 2 above points   this will work

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This is a very old thread  I had a new finding today  I have created an activity  I put it in another package by mistake   In the newly created class  eclipse was not able to resolve R   I tried all the ways mentioned in many places but I failed to notice that I put it in a different package  After struggling for few minutes I noticed that I put it in wrong package    If you are not keeping your Activity in the activity package  you will get this error

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What worked for me is installing  Android SDK Build-tools   Open the Android SDK Manager and install the Android SDK build-tools  It also helped to update the Andriod Development Platform in Eclipse  Help   check for updates

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I m guessing you just copy and pasted the codes  or not  Either way check your AndroidManifest xml file  see if the package name is correct

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I solved my issue with this by putting the resource files directly in the directory specified by Android   I had mistakenly believed that R raw could contain the entire file directory of my resources   All files must have R raw as their direct parent directory

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In case anyone is interested  I might be saving your life here   I had the error  R xml cannot be resolved  slightly different on a GLS project  Hmmmm  After looking in R java  I found an auto-generated class  XML java   I think  was not there   Solution  It needed a new folder in res  res xml and a file called default values xml in there  Then all was OK   Just in case you have not got that file  it s    lt  xml version  1 0  encoding  utf-8   gt   lt PreferenceScreen     xmlns android  http   schemas android com apk res android  gt   lt  PreferenceScreen gt

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In my case  I had an error in my AndroidManifest xml  Others have said that your XML files must be free from errors  but I was only looking in the res  folder  Find and fix as many possible errors and the problem may well resolve itself

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Try to make your new XML layout file name lower case  For example  use my file xml instead of myFile xml

[android] R cannot be resolved - Android error

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