Develop Reference

Why R.java is not imported automatically in my IDE?

In my new project I always have to import:
import com.abc.R;
or the problem: "R cannot be resolved to a variable" appears.
But in my other project I don't have to do that.
What is the difference and is there any problem?

This might happen when you have an error in your xml layout and then you try to clean the project, you get this error.
Try to build the project, if it doesn't work, start a new one and copy the contents. Now that should work.

In general, to make it work:
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.
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. Turn it on and build your
project.
Mistakes in your xml views could cause the R.java not to be
generated. Go through your view files and make sure all the xml is
right! Remove, if any import android.R;
Restart your IDE.

Perhaps in your other projects the classes referencing R are in the same package as R?

eclips project is not rebuild after clean

I have map Project in Eclipse IDE and I Cleaned It From Project Menu.It deleted mY BIN Folder and also Gen Folder.Now I Have tried Much BY Build Manually and also from Android Toold To Fix Project Properties But It is Not fixing the Problem and In Source Files R is Red underlined and Bin and Gen Folder are Not Being Created again.Please any oNe Help me to To Get Out OF this issue.

There may be Some Reasons :-
1.from Project-> checked Build Automatically.
2.There Should not any error in your xml otherwise R file will not build automatically.
3.Refresh the project & Restart eclipse.

First backup(e.g. zip) your whole workspace before you start experimenting. Then try to remove IDE specific files e.g. .project .classpath and setup it again. If it fails create new project with similar configuration and simply copy your libraries and source code into new project. Eclipse IDE is pure magic sometimes.

If you have imported this project, then try import as a general project, not as android project. then in build path see if all libraries are present, then run as android application

you have to try till you succeed process.
Try following steps:-
Make sure there is no error any any of your .xml files .. check in
Problem section..
Make sure all your impoert are correct, Eclipse sometimes do import
android.R; on its own, so remove that..
If that doesnt succed make some changes in Manifest file say remove a
word save it then again add that word save it.. I know it doesnot
make sence as code but making changes in Manifest files rebuilds the
workspace an so is the auto generated files. then clean build your
project.
Restart Eclipse as last resort..

try the following steps to help us
remove if imported import android.R; and after like example if your application package name is com.example.project you need import like import com.example.project.R;

Android R.java file is not creating for my applications

I am creating new Android application in my Eclipse.Application is created but the R.java file is not creating,I am getting errors R cannot be resolved.
IS there any issue in my android-sdk?
Thanks

Try Clean and Build
if it does not work please close the eclipse and open it again
It should work.

You can try following things.
1)in project tab(topbar) there is clean option try that, if your code is fine it will regenerate R.java file
2)if you imported import android.R.* statements, remove it, You should add your.project.name.R.* instead;
3) there may be errors in your xml files, check error viewer it should show errors there.

Check this. have you imported import android.R;in your project. If have means remove this import android.R;. clean and Rebuild your project
import android.R;

No generated R.java file in my project.
R.Java not generated.
R.java file not getting generated.
When you clean and build your project R.java gets generates automatically. Try the above links.

There are 2 ways to solve this problem:
1) In Project Explorer, Right Click on your Project, then go to Build
Project
2)in project tab Go to clean option, if your code is fine it will regenerate R.java file

Clean your project and try again it will help u

From Eclipse Menu Bar;
Enable Project -> Built -> Built Automatically

Android R.layout.main not getting resolved

I am new to android and making my first application.
I have a problem resolving R.layout.main
The main is auto generated in my res/layout.
I have already imported android.R
but it is still not resolving "main"

If you are creating a new application for android in eclipse, then R.java file is auto generated in your application's /gen directory, And your R.layout.main is resolved automatically, For that you don't have to import any R file in your activity class..
Just remove android.R any any other R file import statements, Clean and rebuild your project it works fine..
Also make sure Your project doesn't have a any error, If its present then it s prevent to generate R.java file in /gen directory..

Instead of android.R you must import the your package name.R...

Have you imported "your-package".R?
You can find it in "gen" directory.
If R.java is not auto generated, probably there is compile time error, check your ide's messages.
By the way, you define "your-package" in your AndroidManifest file.

Quick solution:
Remove android.R and just import your package.R file by doing Ctrl+Shift+O
More info:
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.
Look at your imports. There is android.R imported, 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.

R.java file should be auto generated, but I could not find it. So I just deleted my project and created it again and this time everything went fine - I've got R.java and the error resolving R disappeared.

Problem: Not resolving R.layout.main
Solution: In your Activity Java class import as following
import [Package Name].R
Example >> import com.example.tutorial.R

r.string error "cannot be resolved or is not a field"

I just opened an older android app project and all of a sudden numerous R.string._var_Name errors were found. If I add "import android.R" then the _var_name becomes an issue saying "cannot be resolved or is not a field". The translation is in /res/values/strings.xml . Any ideas why the error exists?

If your class files are not in your root package, you'll need to import them at the top of your file like this:
your.package.name.R

In my case import android.R was usually the problem. I then removed it and build again (eclipse) and than it worked. Cleaning the project often helps too.

Go to Project>Properties>Builders and see if 'Android Resource Manager' is checked.
Or go to Project and do 'Clean' to rebuild the project.

I had that problem when modify the samples of vuforia. I resolved that adding the string name=... necessary in the file strings.xml file.

add import com.example.android.yourprojectname.R to your imports at the top of the file in which the error is occurring in, replace yourprojectname with your project/app name. This should resolve it.