I am trying to run a project but there is a red exclamation mark over the project name. When checked in Problems, its throwing an error "project is missing required library". The library is pointed to android.jar located in some path. When checked in package explorer, I found the android.jar in Android 2.3.1 folder structure of project in package explorer. The android.jar located in Android 2.3.1 folder is pointing to some other path. Is the build error occurring due to the difference in paths for android.jar files? I have imported the project.So, how should I modify the path which is shown in the problems window? I am newbie to android and so pls help me.
Thanks!!!
The easiest way to resolve this common problem is to re-associate your project with an SDK version. You do this by opening project properties, clicking on Android, select a different SDK version to that which is currently selected (if one is selected at all), click okay, and then repeat the process to switch back to the desired SDK version, if desired.
I tried Phillip's answer and it didn't work in my case. Another place to look is opening project properties and clicking on "Java Build Path" -- if your project used some external JARs, check to make sure the links haven't been broken. If they have, reimport them again and remove the missing ones.
Import your library through the option: File/ Import... / Android / Existing Android Code Into Workspace, and not by creating a New Project and referencing the other (if you did this way).
I had this same problem and solved that way. As example, there is a PDF which demonstrates how to import other projects [Look at the page 28] (The material are in Portuguese)
I'm working on a team project. I included a .jar file in Build Path and committed to SVN. When I updated code in my working directory, a new folder appears in Eclipse called "Android Dependencies". If I let it be there, my program runs; If I remove it, my program reports a ClassNotFoundException.
Now how to fix this ClassNotFoundException?
For the people whose heart dropped when they read the comment that deleting the Android Dependencies virtual folder will destroy your project, there is an easy fix.
Right click on the destroyed project
Select "Android Tools > Fix Project Properties" in the dropdown
I hosed my project dependencies when trying to set up my git repo, and this is fixed it.
Android Dependencies is a virtual folder where Eclipse shows what JAR files the project depends on. It's not a physical folder; you won't find it on your hard disk. And the folder is not checked in into Subversion.
Do not delete that folder. You will destroy your project.
To fix it, just revert to an older Subversion revision and check it in again.
I've had a similar problem after setting up a git repo with my project.
The problem was that the appcompat import lost its folder reference.
If the 'Fix Project Properties' mentioned doesn't work for you try this:
Go to Project > Properties
Go to the 'Android' tab
Under 'Libraries', if there's a red 'X' next to the appcompat folder, remove
it then hit 'add' and add it in again. The reference should show a
green tick now.
Save and clean the project if needs be
If you also have marked project build target below API level 16 in the Android project properties, the error is going to come because prior to this level, there was no Android dependencies.
This question already has answers here:
Developing for Android in Eclipse: R.java not regenerating
(64 answers)
Closed 9 years ago.
In Eclipse, I've created a project from a source and now it shows errors - "R cannot be resolved to a variable". From what I found here, I had cleared and rebuilt the project, but still the R file doesn't appear in the /gen folder.
Any ideas?
Dont worry. First you may clean the project, then run the project. If this does not work then follow the following links:
Here is the best way to solve this problem: [Android Development- Where is my R.Java file?][2]
R.java not regenerating
R cannot be resolved - Android error
R cannot be resolved to a variable
R cannot be resolved to a variable -- mailing list entry
Fixed: R cannot be resolved to a variable
If Clean/Rebuild Project doesn't work try to check our package name in AndroidManifest.xml.
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.
For me the error got fixed by making some changes in Android SDK Manager.
Whatever be the latest API level available, install its "SDK Platform". For me latest API level available was 16, so I installed its's SDK Platform as shown in the image below. It works fine now.
Cheers, Mayank
Did you just update both sdk and adt(from 21 to 22), then you need to install a new item: Android SDK Build-tools
Refer to:
Eclipse giving error, missing R.java file after recent update
For me somehow the Project properties; Android; Project Build Target was not set. I chose a Android version there (e.g. 4.2) and it fixed it.
for me, the best solution to suggest to people that have problems with the "R" file would be to try the next steps (order doesn't matter) :
update ADT & SDK , Eclipse and Java.
remove gen folder , and create it again .
do a clean-project.
right click the project and choose android-tools -> fix-project-properties .
right click the project and choose properties -> java-build-path -> order-and-export. make sure the order is :
Android 4.3 (always the latest version)
Android private libraries
android dependencies
your library project/s if needed
yourAppProject/gen
yourAppProject/src
make sure all files in the res folder's subfolders have names that are ok : only lowercase letters, digits and underscore ("_") .
always make sure the targetSdk is pointed to the latest API (currently 18) , and set it in the project.properties file
For me, there was a missing slash at the end of my SDK. In Eclipse > Preferences > Android > SDK Location
For example, change
/home/matt/android-sdk-linux
to
/home/matt/android-sdk-linux/
your android manifest must start with correct package
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="HERE - Correct package NAME"
android:versionCode="1"
android:versionName="1.0" >`
I got similar problem and solution I found out was in resources any of
the file aka background, sound etc must not contain capital letters or
any special symbol other than _
What you really need to do it just install "build-tools" from sdk manager,
and r.java will be generated automatically.
I had the same error. Error was that, I had placed a file in res/raw folder with invalid filename.
As soon as I corrected the file name to a valid one, error was resolved!
Allowed characters for naming a file:-
1. a-z
2. . _
3. 0-9
4. no capital letters
Capital letters were the issue in my case!
Sometimes you can accidentially add an import to "R", so if at the top of your code you see some weird import about that that you did not add yourself, delete the reference, and everything should go back to normal
My problem was strange and took some time to find. Somehow the package of the src file changed so that the last entry in the package was deleted. So for example initially my class MyActivity.java was in package com.abc.client.test.app but after I added a user permission, the app got removed and the package was renamed to com.abc.client.test. I don't know how it happened. Renaming the package and putting the java file in the correct place fixed the problem.
I found this problem when trying to run the Notepadv3 programme from Googles 'first lesson'..
For me it was an issue with the xml file, due to the API level I was using. I renamed each case of Match_Parent to the older type of Fill_Parent. Oh and if you have already auto-built the project then you need to delete 'import android.R' on NoteEdit.java and Notepadv3.java, clean the project (click 'Project', then 'clean...') before saving.
Solved it for me. Came from this post Android NDK r4 san-angeles problem
Can't believe Google dosen't warn of this problem - I have been setting up another PC to start programming again and even with a bit of prior knowledge this was a pain.. How do you set the API when importing an existing project??? Can't see where there is any dialogue option when you 'File' 'Import' etc ..
Scamparelli
Check the androidmanifest.xml file and layoutfolder xml files. They should be created properly as the starting and ending clause in xml should be placed properly. Update the files, clean and build. And all set!
I had this problem and none of the other guides helped, and then I realized I didn't have the java jdk installed on my system. If you haven't done this either go download the version corresponding to the version of eclipse you installed (x86 or x64)
It is possible you have an error in your *.xml files: layouts and etc.
Try to modify AndroidManifest file.
For example add space and delete this space. After this OPERATION, save project. Resources will be refreshed. It can help.
I solved the problem with resolving R resource on fc19.x86_64 and ADT v22.0.5-757759 by installing additional libraries after Fedora and ADT upgrade.
yum install ld-linux.so.2
yum install libstdc++.so.6
yum install libz.so.1
Those libraries are required by adb (Android Debug Bridge version 1.0.31).
Then restart Eclipse and perform project clean Project->Clean check project you would like to clean.
Hope it helps :)
Project > Clean...
usually regenerates R.java file located in gen/com.mypackage
In my case, R.java wasn't getting generated because of a hierarchical parent error, which in turn was cured by updated one or more Eclipse plugins (Go Eclipse-->Help-->Check for Updates)
I got this error when I added a js file to the res folder.
An error indicator was set on the res folder icon. In all the classes where I used R I got this error.
I moved the js file to the assets folder and everything worked.
Problem was eclipse was not generating R.java.
To resolve this issue please go to project->clean... and select your project and select ok and then clean and build project and import your package name R file(Ex com.demo.R). It works.
This can happen when the android naming convention isn't followed. Check if you have placed a file/photo into one of the android folders and make sure that the file name contains only lower case letters
I know this is an old question but I just solved my own version of it and perhaps this might help someone.
After two days of tearing my hair out with this, I finally got around it by deleting the raw folder, then recreating it and dropping the file(s) back in.
After that, another Project > Clean and it at last compiled.
I got this when I renamed a project. Although the project is renamed, some references are not. Clearing lint, and then rerunning lint helped. (Right click project > Android Tools > Clear Lint Markers, then Run Lint)
My setup was broken after a recent update where the SDK build tools need to be installed separately after the SDK installation. So build tools update + Eclipse restart fixed this for me.
Credit goes to the Android reply here
When other solutions fail, select your project and delete it. MAKE SURE YOU DO NOT REMOVE FILES FROM DISK.
Then use file>import>existing android code into workspace, and select the location of your project.
I been having this and i did trace it back to the layout files.. It happend to me again however i could not find noting in the layout files. I looked in the string.xml and there was it.. one of the string names started with cap and that was causing the problem.
Fix any XML formatting errors in the XML Files in your /res/menu folder.
Might be a compile time error from the XML file being improperly formatted.
If I run my project this error will come build path problem how to solve this error.
error:
Description Resource Path Location
Type Project 'videothumb' is missing
required source folder: 'gen'
videothumb Build path Build Path
Problem
The project cannot be built until
build path errors are resolved
videothumb Unknown Java Problem
Can any one help me?
Try to clean project and if it still doesn't help close and then open project.
IF you are using eclipse then do as follows:
right click your project.
select build path-->configure build path.
update all the broken links in all 4 tabs.
Go to project-->clean [project will be found at top menu of eclipse.]
Clean your project.
Its done. For any further explanation comment on my answer.
Hope this helps.
Edit:
Here you go:
As you can see i'm at source tab of configure build path and i have only one folder here named ATalk/Src. likewise you can have number of folders.
Check for red cross mark on folder. if its there then your folder path is wrong means link is broken for that folder.
Same way you can check in Libraries tab. There you will find list of jars in your project. If any of them have red cross then its path is missing. So update all such red cross paths.
As you can see i dont have a red cross on my folder means it is at correct location.
Hope you get my point.
EDIT:
I just noticed that, according to your screenshot, the problem seems to be that the adb tool is not found. Now I might be wrong but I think that as of Android 2.3 (maybe even earlier) the adb tool is expected to be in [path-to-your-sdk]/platform-tools folder, not in the [path-to-your-sdk]/tools folder. The later path was used in earlier SDK's and your problem might be caused by such a simple thing that you have an outdated Android plugin in Eclipse.
OLD, IRRELEVANT ANSWER:
I've seen these kind of issues in Eclipse environments when I have some kind of error in my XML files. Malformed errors (that violate the rules of the XML structure) are often treated as "syntax errors" and are shown directly when you write them or when you try to build your application.
Other errors, however, like giving invalid references (giving a dimension where an integer is expected, for example) are not always highlighted with file name and failing line number (I'm not sure if this is bug in Eclipse's android plugin or even if it's a bug at all).
These kind of errors you'll have to hunt down manually and rebuild your project (as dcave555 sugested). This is really boring work if you have many XML files with many changes in
I think the path should look like this: /home/embdes/projects/android/android-sdk-linux_86
The problem is because of your Android build path settings. Try to check:
Window > Prefereces > Android > Build path
it should properly set to your Android SDK
I created a Hello world app but get this strange error:
The project cannot be built until the build path errors are resolved
I haven't changed the project, jut created it and tried to run it.
to avoid that annoying problem i have 3 solutions that worked for me.
Solution 1)
delete your generated R.java file
inside your gen/ folder
Solution 2)
a)Delete your project from Eclipse
(i said ONLY from Eclipse, uncheck option: Delete project
contents on disk)
b) import your project to Eclipse:
file > Import > Existing Projects into
Workspace (Look for your project
previously deleted from Eclipse) >
Finish.
Solution 3)
make Solution 1 then Solution 2
It is either a spurious message you can solve by forcing Eclipse to recompute its library paths
I found the resolution for this at Scott D. Strader's blog.
To summarize the solution I only needed to add a library to my project and then remove it to force Eclipse to perform the necessary actions to resolve the problem. I would post the detailed steps here but I don't want to steal his content.
The resolution was to force a resave of the selected projects (and their .classpath files):
Open the project properties
Select Java Build Path > Libraries
Add a new, arbitrary library (to be deleted later) > OK
Wait for the workspace to refresh (or force a refresh of the project)
The error(s) will go away
Remove the dummy library
Note: as the OP mentions, a simple restart of the IDE can be enough.
Or you actually miss one critical library like a JRE library:
I needed to add the JRE library to the project for it to run. Not sure if this was due to the updated version or something else…. Any way this fixed the issue:
Project > Properties
Java Build Path
Libraries tab
Click add library
Select JRE System Library
Next
Finish
Sounds like you are missing an import or a jar. In your project in the project explorer there should be a red x on the file icon that contains the error.
In addition to the listed answers, there is one other scenario I've seen this error appear when using the sample projects included with the Android SDK. For some reason, the generated R.java file can be invalid or corrupt. You can get around it by expanding the "gen" folder in the Package Explorer and deleting the R.java file. It will immediately get regenerated and the error goes away.
Right click on your project, choose "Build Path", "Configure Build Path" -> and choose Android 2.2, or that target you specified when you created your project
I have had similar issues. for me simply closing the emulator and re-running the project works