I tried to clean my project through Project->Clean and then suddenly all my R.java files in all my projects have been deleted. I don't know how to regenerate it now because I have hundreds of errors now...
How do I get my R.java files back?!
This happened to me yesterday, there are a few options you can try.
First try building the project again.
If that fails, try removing the gen file in eclipse and clean again
If that fails, try checking your xml files if there is any error
If everything fails, create a new project and copy-paste all layouts/src files to the new project.
EDIT:
I searched for this yesterday, and I tried every possible solution, but only creating a new project helped.
Do follwing tasks:-
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.
Or If no resource errors then try this step also 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.
Right click on your project in Package explorer in Eclipse. You will
get a number of options. Go to Android Tools-> Fix Project Properties
so see if that helps.
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).
R.java files are generated automatically by Eclipse. Check if you have Project > Build Automatically checked or not. If not, check it and it should resolve your issue. Alternatively, check your project for other errors, preventing the R.java files form being generated.
If the issue still persists, try restarting Eclipse.
I am working on one android application. Don't know why but i am not able to regenerate R.java file.
i also searched a lot about it. and also tried all the solutions i got from various place. but R.java is not generated.
if i import my project in another computer, then it is working fine. only have problem in my eclipse. :(
i also solved all the lint errors, warnings and also tried to clean and build project. i also checked my all .xml files as well as all images. all is perfect not any special symbols or uppercase. and and tried all the tricks which i got. but now able to generate R.java file.
please help me.. Thank in advance...
Edit :
right now i am getting one error like
Description Resource Path Location Type Error executing aapt: Cannot
run program "..\Android_SDK\build-tools\18.0.1\aapt.exe":
CreateProcess error=5, Access is denied: CreateProcess error=5, Access
is denied TestProject line 1 Android ADT Problem
Occassionally I am also fighting with this issue. Sometimes it's tough, but it's usually that something is wrong with your /res/ files. Usually XMLs.
First try to Clean your build, but you did that already.
Look for malformed XMLs, they do not have to be marked in red at first, but try to open them all if you don't see them popup in red. Check that you don't reference ids to another views in styles.xml, check for invalid characters in keys, check for invalid/unescaped characters in content of xml entities.
Also check properties of your project and make sure that all Java Build Path components are checked (Order and Export). Mainly Android one. Sometimes it happens to me, that it's unchecked making my project unbuildable.
If it works on another computer, it seems the code is fine. The problem seems to be either your toolchain or your Eclipse workspace.
Try the following:
If you use Android SDK Tools 17 or higher, make sure you install the corresponding Android SDK Build-tools in Android SDK Manager.
If the above doesn't help, create a new workspace and import your existing code into it.
This is common problem, which can be caused by many different situations.
What always worked for me:
If your R.java is not generated, your project is flooded with errors saying that class R is not recognized (obviously). Usually, somewhere between all those R.java errors, there was one other error (with different that all others) which is often overlooked because of hundredths R.java related errors. If i fixed this other error, R.java is generated after clean/build...
Edit: the "other error" i am talking about that is preventing your R.java to regenerate, is often found somewhere inside resource XML files...
The problem is in your installation path of Eclipse. Just check that your path doesn't have any spaces where you have installed Eclipse. And name should be proper for the Eclipse directory.
I also had the same problem because my Eclipse installation path got spaces in it, and my Eclipse directory name got changed to some symbolic name. When i renamed it to Eclipse and make the installation which contains no space, it got worked.
For example if Eclipse directory path is like
D:/New Folder/Android/Eclipse
Then it may got problem because of space between "New Folder".
Check your path and directory name and if it worked then check my answer please.
I was struggling with this issue for past one hour. I just solve it by
Remove the ".metadata" file from the workplace directory.
Then start the Eclipse.
Import the project from the workplace by File -> Import -> Existing project into workplace under General tab.
The R.java file will be generated. You need to import all other project that were in your workplace the same way.
Hope this will help someone
other answers relating to this did not help me out. Hence, I am posting a new question. I am trying to test a sample app of android that comes with their SDK. I get the error "R cannot be resolved to a variable". Looks like my R.java is not being generated. I don't know if I checked in the right place. I checked in the 'gen' folder of where I had downloaded my SDK and could not find the R.java file in the app which I am trying to test.
Could you please provide me with some ideas?
Thank you so much.
It happens when resources are not compiled. If you don't use automatic builds then just build your project. Otherwise it may happen because of some errors in resources.
I had the same problem(there was nothing under gen folder) and tried other solutions such as "cleaning project, checking if not android.R package is imported instead of mypackage.R, moving gen folder over src in java build path => order export tab and checking permissions of SDK executables" but none of them solved it.
Finally when I was checking one of the layout xml files in the res=>layout whether it has a problem or not Eclipse warned me with "The project target (Android 2.3.3) was not properly loaded" text. So I wanted to double check Android SDK Manager from Eclipse and found out that related SDK had an update. I did not see it before because it has a confusing structure with new or installed check boxes in my opinion.
When the 2.3.3 SDK updated all the problems gone...
Just clean the project and build again.
This is the most common problem I've found while developing for android.
Also try this Link for a detailed description about this issue.
Try to remove the read only in the properties of the sample sdk folder. That fix my problem i guest. Then remove the project in the eclipse. Restart eclipse. Then import it again.
I am developing a simple Android application. But when I run Eclipse, it shows the following error:
Your project contains error(s), please fix it before running it.
I can't find any error in my project or there is no error in my application.
There is a red cross under the application name but it is not under another file name.
Does anyone else have this issue?
That usually comes from errors in the build path.
If you're using eclipse, there is a view you can add that lists all the errors called "Problems":
Otherwise, you can try to clean the project, and that usually solves a few problems.
Finally, if you add or alter resources from outside your IDE, you'll want to reload the resources and clean.
EDIT (Comment by anonymous user)
This can also be caused by an out of date "Debug Certificate" fixed as follows:
IF ALL FAILS THEN THIS GOTTA BE THE SOLUTION:
Delete your debug certificate under ~/.android/debug.keystore (on Linux and Mac OS X); the directory is something like %USERPROFILE%/.androidon Windows.
The Eclipse plugin should then generate a new certificate when you next try to build a debug package. You may need to clean and then build to generate the certificate.
This is also another fix for the "setContentView(R.layout.main);" error that says it cannot find R.layout.main when it is actually generated. (R cannot be resolved to a variable).
This is also another fix for the error "Your project has errors..." and you cannot find any.
Clean and rebuild are still necessary after generating a new debug certificate.
First go to Window -> Show View -> Error Logs in menu. It will display error logs if you have any. Then try to clean the project and build it again.
Well, in my case some libraries were addressed twice in the:
Project >> Properties >> Java Build Path >> Libraries
I just had to remove the duplicate and it worked fine without any cleanings or refreshing.
I saw this with an existing project. I had made a few edits, but hadn't imported anything new. Restarting Eclipse didn't help.
Project->Clean did solve the problem.
I come across this error often when I import a new project in my workspace.
Reason: Some necessary files (Like R.Java) is not generated in its respective packages.
Cure: Clean and build projects, All the files that needs to be auto generated will be there on place after building the project.
Best Luck.
This is happened to me. After format of my system,
When i import project it shows same error
remove first debug.keystore file then goto -
Project -> Project properties -> select library -> remove -> add again libraries.
It's working for me......
Go to projects menu, click on clean menu item.
After that close the eclipse and reopen and try compiling..
It is software glitch you find some times.
it can also happen if you move required files. Simply check Problems View (menu window -> show view -> Problems) as told here
I had this exact same problem. One solution that would work would be to create a brand new project, but I don't think there's any need for that. For me the problem was that the debug certificate that gets auto-generated had expired. Deleting this file allowed Eclipse to rebuild that file, which solved the problem. You can't run an app with an invalid certificate, whether it be a debug or release certificate. Note that cleaning my project did not work. For more information, see:
"Debug certificate expired" error in Eclipse Android plugins
Recently I came across this error. I was really in a corner with no help, then I figured it out. This error can occur for the following reasons:
An error in the project code
Improper linking of external library files to the project
Most important: if your debug.keystore file is expired.
The first 2 cases are easily identifiable but the third one is like searching a black box in a dark room.
So in addition to Project -> Clean, remove your debug.keystore file also.
I am using Mac + Eclipse so to remove, I wrote the command rm ~/.android/.debug.keystore in a terminal.
Is there a way to ignore existing errors in project. Something similar what eclipse allows in case of java projects.
In my case the errors exist in jni directory. The errors are shown even though ndk-buid succeeds. So all i want to do is to ignore the errors reported by eclipse.
If the errors are indeed errors then i should get unresolved symbols during ndk-build.
I have ensured standard android includes are there in include path.
Also my project is of type android/c/c++.
I have two builders associated with the project
1. statndard android builder
2. custom ndk builder that ive explicitly created.
Simulate your self some error in class. Then save it and it would show more errors than you simulated. For me it was incorrect import and this helped.
I have had a similar problem.
Under "problems" tab I have found an error saying "Error generating final archive: Debug Certificate expired on 2/22/12 1:49 PM"
So my advice is to look in the problems tab to get some more info.
Bye
If none of the above solution work, you should check the READ ONLY property of the Project folder, if it is Read-Only, the compiler will not be able to overwrite the resources, R.java and other dex APK etc files and hence this will occur..
This happened to me and I fixed after a long struggle..
Happy Programming.
For some reason eclipse only showed a ! error on root and didn't specified what error it was.
Go in Windows -> Show Views -> Problems. You might find all previous errors there, delete them, do a clean build and build again. You'll see the exact errors.
Eclipse shows an error on android project but can find the error
I had this exact problem when trying to run the Doodlz app, from the book Android for Programmers, on Mac OS X with Eclipse Juno.
After downloading and unzipping the demos from the book, I forgot to change the permission of the files. They were read-only on my system so this was the first issue.
The second issue was solved by selecting a build target on Eclipse. This was fixed by going to: Project > Properties , and clicking the Android field on the left panel to be able to select one option as the Project Build Target, which in my case was:
Target Name Vendor Platform API Level
> Google APIs Google Inc. 4.0.3 15
Then cleaning and rebuilding the project showed no errors.
Finally, to run the app right-click the package (at the Package Explorer tab) and then select:
Run As > Android Application
Simply Deleted my debug certificate under ~/.android/debug.keystore and Project->Clean did solve the problem.
Delete the .android folder from your Documents&settings\User\ on XP and \User\ on Win7. Recreate the AVD again and create a new project.
What caused this problem for me was none of the above, but simply that I'd left the "debuggable" attribute to false in the manifest.xml file after doing a release. D'oh!
Of course neither the LogCat, Error log, Console, or Problems window alerted me to this..
I had the same error, when I copied a project to another computer.
I then checked all properties of the project on both machines, and the only thing that was different was the order of items in Java Build Path - tab Order and Export.
I moved the items Android X.X.X and Android Dependencies above the other 2 in the list (in my case, src and gen folders) and voila, it worked again!
I'm not really sure if the different order was actually the problem, but at least changing it (and saving the properties again) seemed to help...
I had the exact same problem after updating the SDK and ADT.
My issue was resolved by deleting the .android folder (hidden) under C:\Users\USERNAME\
This happened to me when I was experimenting with Maven.
Right click project -> Maven -> disable maven nature
corrected the problem for me.
Yes, this is a rather cryptic message. If you've got a faulty project (say one you've been working on in the past) then you'll get this message (and no messages in your current project's Problems / Error Log panes).
You may just want to run your current project. This may be perfectly fine. Just click on the down arrow to the right of the Run button to select your project.
Try changing your workspace. I am not sure this is the exact solution . I did face the same issue for sometime untill i changed my workspace.
In my case, it happens with ADT 22.
I choose not to create Activity.
After I remove the "appcompat_v7" as library project. I works.
I had similar problem where I couldn't run my project yet didn't see any problems in the code. In Error Log panel it said something like "Cannot add P/ to the list of segments P/ in as a parent".
Restarting Eclipse solved the problem.
I have a problem I can't seem to get around. I've created a project in Eclipse (I recreated it from another project that I thought was corrupted). There are no visible errors in any of the files, including the .xml files. However, the project root [project name] itself has an error (red 'x') and so I can't run it.
On a side note, in the default properties file the line:
target=android-4 is underlined in red with the note that 'android' is not spelled correctly. I have not altered this file since it was generated.
Any clues? Target is 1.6, sdk 4. And I'm new at this :)
You may have already tried this unsuccessfully, but if not, you might want to try the Android Tools > Fix Project Properties action from the context menu of the project root.
Eclipse also thinks android-4 is misspelled in my default.properties, so I doubt that is the cause of your build problem.
Does the Problems view describe any issues? (Window->Show View->Problems)
You could also try cleaning the project in eclipse. Project->Clean..
if the error message you get is
The project cannot be built until the build path errors are resolved.
this might help:
Open the Project -> Properties
Select Java Build Path -> Libraries
Add any new library (to be deleted later) -> OK
Wait for the workspace to refresh or force a refresh
The error should go away
Remove the dummy library
You can stop the spelling error by adding that word to a user dictionary, but a spelling error wouldn't prevent a run.