I am a new Android developer (4 weeks into porting my iPhone app to Android). I have 8 projects (the app, and 6 small UI experiments, and a vanilla Hello World project that I just created with Eclipse). All fail to compile, and the issue is that every reference to the generated file R is flagged as "R cannot be resolved to a variable".
Up until yesterday afternoon -- every project compiled and ran (albeit very slowly) in the Android emulator. I've changed something, and since yesterday, all projects fail to compile, all in the exact same manner "R cannot be resolved to a variable". I every case, the generated files are missing. I believe they disappeared as I tried to clean and rebuild each project in the course of debugging this problem.
Two things that I know changed when this problem started, but that I can't say caused the problem, were: 1) shifting to debugging on a real Android device (a Samsung Galaxy Tab 2, which worked like a champ after struggling with the slow emulators), and 2) allowing Android (and perhaps Eclipse) to update themselves from the web.
I've spent many hours trying other user's suggestions and none have helped. Most suggestions refer to file naming issues, xml syntax errors, but I haven't changed these files and filenames since compilation was working. I have tried:
cleaning and rebuilding the projects
checking for subsequent updates to the Android SDK (and there were 2 subsequent ones)
Eclipse->File->Android Tools->Fix Project Properties
making small source changes to force rebuilding
rebooting Eclipse, as well as the Mac host, adb, the emulator, the Android SDK Manager
deleting a project, restarting Eclipse, and adding the project back in (bad idea - this fails with an error "Failed to load properties file for project 'ListViewFragmentTest'"
creating a brand new Android App project, which has worked many times before, but now fails
There's something going systematically wrong, and while I won't claim all these projects are bug-free, they did run up until 6pm yesterday, and then all stopped compiling thereafter.
I wonder if anyone has other suggestions, before I embarking with a complete reinstall of the development environment?
My environment is:
Macbook Pro (OS X 10.7.5, 8GB RAM, 2.53GHx Core i5)
Eclipse (Indigo Service Release 2, Build: 20120216-1857) (too old?)
Android SDK Manager Rev 22
Android SDK Tools (22), Platform Tools (17), Build Tools (17)
API's 11-17, all up-to-date
Seems like lots of people experience trouble with missing generated files (R), and I have had trouble when I've had layout XML errors as well, but that doesn't seem to be causing this problem. Thanks in advance for your help!
I am not sure but you are facing issue of R.java file is not getting generated after updated with ADT rev 22.
If this is the case then here is the solution:
Hope you know Android studio has gradle building tool. Same as in eclipse they have given new component in the Tools folder called Android SDK Build-tools that needs to be installed. Open the Android SDK Manager, select the newly added build tools, install it, restart the SDK Manager after the update.
Check in the Java build path library, whether "src" check box is checked or not.
If you are using any additional Libraries then make sure libs/android-support-v4.jar is same for project as well as the Libraries.
Thanks everyone. None of these suggestions resolved my problem. And while I'm curious as to why it happened, I was more impatient with not making any progress. I've reloaded Eclipse and the Android tools (this time with the bundled version from developer.android.com), and everything is working smoothly again.
Related
I know there are a multitude of questions across various forums that touch on this issue but nothing has helped thus far.
I use Eclipse Photon for my IDE.
I installed the Android SDK via Android Studio.
I recently moved to a new machine and since then I get these errors when trying to build the project. Actually, the first image occurs when I first open Eclipse. The second image is what I see when building (I cleaned beforehand).
Many solutions suggest reinstalling platform tools/build tools/the entire SDK etc.
So, I did this:
1) Closed down Eclipse
2) Opened Android Studio and went to SDK Manager
3) Unchecked and uninstalled all the options highlighted in the images below.
4) Once uninstalled I restart Android Studio and reinstalled all of them.
5) The errors noted at the start of this post persist.
Any ideas what I can try next? It seems every machine move/upgrade causes build issues. It's the main reason I dislike coding for phones, it's not the coding, it's the dev environments!
I have a problem with creating Android Application project in Eclipse on my Mac. When I start Android Application Project Wizard after clicking "finish" in the last step, this window appears:
I've been trying to solve this for hours, but none of the solutions I've found on the internet worked for me (including this). I didn't try to reinstall eclipse itself, but to I don't want to do this. What's the solution to my problem.
UPDATE:
I removed Eclipse and sdk from my computer and downloaded the whole ADT Bundle from here and switched workspace but actually I am still getting the same Errors.
What I found up on the internet was that you could have upgraded your java. So this occurred. The solution to this problem for Mac is to edit the Eclipse.ini file to use java 1.6 .The code Below will work :
-vm/System/Library/Frameworks/JavaVM.framework/Versions/1.6.0/Commands/java
Start with a clean slate. Unistall Eclipse and redownload - Eclipse is a very big program and can be very buggy at times for no reason. While it is not the quickest solution, ensuring that Eclipse was properly downloaded and installed will provide a good foundation for the future development of you Android applications. Did you install Eclipse just for Android, or did you have a pre-existing copy and want to install the Android SDK?
I'm trying to learn to develop Android applications and I'm using eclipse, I Installed the android SDK and eclipse and I was able to make a couple of basic examples but suddenly I updated the SDK with the lates reviews and eclipse is not generating the R.java anymore, I read a lot of forums with the same problem but all responses are releated with errors one the code and errors on the xml's but I just create a new project with all defaults and not touching any line or any configuration and I don't have the R.java so I can't run the project I've clean the project 100 times and I reinstalled everything a couple of times but nothing works, so totally frustrate, I change from my Windows 8 PC to my MAC and I found exactly the same problem. Does anyone have a suggestion?
Thanks
Although I know this question has been asked a million times, I have tried going through many of the stackoverflow questions and none of the answers have worked.
I have an old version of my project that I know worked and built correctly, which I added back into my eclipse workspace. When I clean and build the project, I am given with errors with the R cannot be resolved..
What I've tried:
- Building/Cleaning project
- Was going to clear the gen folder, BUT R.java didn't even exist in there
- Checking through my XML files to ensure there's no errors
- Restarting Eclipse
Extra note:
- My ADT plugin and Android SDK was the LAST version directly after Google released it's updates to merge everything over to Android Studio.
I just solved this problem for myself. I was using the Eclipse Android SDK on Windows 7. The problem was that the Eclipse program did not have permission to create the R file. To fix it I went to "User Account Control" settings in the Windows Control panel and lowered the slider to a lower security level. After rebooting the computer and cleaning the application in Eclipse Android SDK there were no more errors.
I've experienced the same problem a week ago. After installing the beta version of android studio I was unable to run android projects in eclipse. Uninstalling android studio fixed all the "R cannot be resolved to.." errors.
After trying everything I tried one last thing.. which was to update all of my plugins and libraries for Android. This actually solved the issue. I'm sure not that many people will probably have my specific issue since it will eventually go away, but it is a different problem I have not found and a different solution I have also not found...
I faced Simmilar problem, i cleaned project, Restarted Eclipse, and many other things like remove errors from problems,
but it was DUE TO: an Image Name in Drawable it contained Capital Latter i did Re factor -->Rename and Problem solved..
I had a working Eclipse setup with 3.6.2 and SDK tools from version 11, and it has been building my main project just fine for quite a while.
For a different project, I thought I needed to upgrade my SDK to the latest and greatest - at this point API 14 (ICS 4.0).
I cannot even reconstruct the steps I went through, but what happened was that my project would seem to build, but I would see that it would say that it was skipping a post-compiler step, and at the end I would have no APK.
I also noticed that it updated my .classpath so that the output path was bin/classes instead of .bin.
Along the way I tried updating my Eclipse to the latest version (Indigo 3.7.1) but this didn't help.
I solved the problem eventually with help from this post on the Google Android forum:
http://code.google.com/p/android/issues/detail?id=21031
For me personally the biggest issue seemed to be solved as follows (qutoe from comment 25 in the forum post)
"I seem to solve the problem with .apk files not being built automatically until run/debug is used (comments #10, #11 etc.). Go to Windows -> Preferences -> Android -> Build and uncheck "Skip packaging and dexing until export or launch" then restart Eclipse. Works for me."
But there is other useful material there. Different people with different projects seem to have different problems with this setup.
I still don't understand the change in the classpath, but it doesn't seem to matter.
In addition, I found a discussion of installing the ADT with Eclipse Indigo which was helpful here in Stackoverflow:
Eclipse Indigo - Cannot install Android ADT Plugin
I also found that I guess because of various uninstalls/reinstalls, for some reason it stopped excluding my .svn directories from the sources. This Stackoverflow post was helpful with that:
Why is eclipse trying to copy my .svn folders from src to bin, and how can I make it stop?
Finally: a tip for really and truly uninstalling Eclipse - everybody says there is no uninstall, and there isn't, but there is a directory that Eclipse leaves in your home directory (in windows 7 under c:\users\) called .eclipse -
Zap it if you really want to start fresh.
In addition, for less extreme measures, there is Project->Clean inside Eclipse, and you can invoke eclipse with "eclipse -clean" for additional cleansing effects. No idea what, but various helpful people along the way suggested trying that to solve problems.
Ah yes - when I first installed Indigo and tried to build, I got a warning that my Java Compiler Compliance level was not up to snuff, which was simply not true - I have only Java 1.6 installed on my machine.
See this post for somebody who had similar experience:
http://marakana.com/forums/android/general/374.html
For me, what worked was simply going to Project, Properties, Java Compiler, then click on Configure Workspace Settings, and click on Ok in the dialog. Didn't need to actually change anything. Just showed it that everything was ok!
Eventually I indeed did clean out my Eclipse and Android installations (including the aforementioned .eclipse directory, and there's also an .android directory in your home directory which you may want to erase if uninstalling the Android SDK Tools doesn't do that - this actually is uninstallable). Installed everything from scratch and then used the additional information provided above and now it's building my APK.
I hope this saves somebody the hours I spent getting my build back in shape.