Can not create 8051 project in Eclipse on Mac - eclipse

I'm using macOS. I have downloaded sdcc for Mac and installed it followed INSTALL.txt inside the downloaded folder (simply copy it to Developer folder), and have Eclipse IDE for Embedded C/C++ Developer installed. Then I installed eclipseSDCC (I don't know if the plugin is platform specific). Seems everything in the right way.
However, when I new a project in Eclipse. I found the Toolchains is empty, so I can't create one. So, how can I deal with it?

Without knowing the prerequisites that renders a toolchain as "supported", these steps enables you to create an 8051 project:
Specify a project name.
Uncheck the checkbox at the bottom that reads "Show project types and toolchains only if they are supported on the platform".

Related

Eclipse Neon 2 & 3 keeps Resetting the Workspace and Plugins

Have installed Eclipse Neon 3 x86_64 bit on macOS Sierra...
Proceeded by picking a workspace folder and installed the following plugins:
Subclipse 1.10.13 (by dragging the icon on to the workspace from https://marketplace.eclipse.org/content/subclipse)
Installed the following plugins (by going to Help -> Install New Software -> All Available Sites and expanded Web, XML, Java EE and OSGI Enterprise Development):
Eclipse Java EE Developer Tools 3.8.0.v201701262139
Eclipse Java Web Developer Tools 3.8.0.v201702270442
Eclipse Web Developer Tools 3.8.2.v201702270442
JST Server Adapters 3.2.400.v201606081655
JST Server Adapters Extensions 3.3.501.v201609071751
JST Server UI 3.4.300.v201606081655
Everything works (plugin functionality) but everytime I close Eclipse, it brings up the default dialog asking for a workspace and is completely fresh (no plugins and preferences...). I have to manually install these plugins every single time I restart Eclipse!
I've deleted the following directories and files:
~/.eclipse (folder);
~/Library/Saved Application/org.eclipse.eclipse.savedState;
~/Library/Preferences/org.eclipse.platform.ide.plist;
~/Library/Caches/org.eclipse.platform.ide;
And, also unzipped Eclipse into a different folder and specified a new workspace and after installing the plugins and restarting Eclipse, its completely fresh again!
This is very annoying and also disappointing...
I even tried to put -clean as the first line of the eclipse.ini file but it didn't help any...
What's weird is that this is happening on my company issued MacBook Pro but not my personal MacBook Pro (which is the exact same model and year as the company issue one)...
Any suggestions would be most appreciated!
Have you checked Eclipse Bugzilla for a similar issue?
It looks like you are running into this:
Bug 507328 - Eclipse forgets about global settings and installed features
It's a feature of macOS introduced with Sierra called "App Translocation" or "Gatekeeper Path Randomization". Try unzipping Eclipse and moving it (drag and drop) with Finder to a different location. This should set a flag which disables Gatekeeper Path Randomization. However, it's important this this is done from within Finder.
The Eclipse Oxygen packages will ship as DMG which will motivate users to drag and drop the Eclipse.app bundle into the Applications folder using Finder. There is an Apple bug here where Apple explicitly states that Finder may be able to opt an app out of Gatekeeper Path Randomization.
To check whether Gatekeeper Path Randomization is happing in Eclipse perform the following:
Open Eclipse > About Eclipse
Click Installation Details
Navigate to tab Configuration
Check the value of osgi.install.area property
If it points to some random looking path with /var/private that path randomization is in effect.
The situation may become more complicated in future macOS versions, though.

ADT opens as Eclipse?

i downloaded ADT bundle for linux 64bit from developers android website
also downloaded adt plugin zip and installed developer tools form HELP --->> INSTALL NEW SOFTWARE.
but when i open eclipse from the folder it opens as eclipse juno (i.e.the splash screen) and not as Android Developer Tools.
can anyone tell me what is wrong or am i openeing it the wrong way?
and i am using fedora 20.
Not sure if I understand your question correctly but ADT is mainly context menus integration in Eclipse. If you are in the Java perspective you can see on the Window menu the options Android SDK Manager, Android Virtual Devices, etc. You also have a perspective to debug called DDMS. You can create new project with template Android Project (or import Android project from existing sources). If you right click in a project you also have and Android Tools context menu, etc.

Error in updating to ADT rev 23 for Eclipse [duplicate]

I updated Eclipse with the new SDK tools (rev. 23), but now when Eclipse starts I receive the error:
This Android SDK requires Android Developer Toolkit version 23.0.0 or above. Current version is 22.6.3.v201404151837-1123206. Please update ADT to the latest version.
No updates were found with "Check for updates". If I try "Install new software", I can see version 23, but I can't upgrade due to the following error:
Cannot complete the install because of a conflicting dependency.
Software being installed: Android Development Tools 23.0.0.1245622 (com.android.ide.eclipse.adt.feature.feature.group 23.0.0.1245622)
Software currently installed: Android Developer Tools 22.2.1.v201309180102-833290 (com.android.ide.eclipse.adt.package.product 22.2.1.v201309180102-833290)
Only one of the following can be installed at once:
ADT Package 22.6.3.v201404151837-1123206 (com.android.ide.eclipse.adt.package 22.6.3.v201404151837-1123206)
ADT Package 23.0.0.1245622 (com.android.ide.eclipse.adt.package 23.0.0.1245622)
Cannot satisfy dependency:
From: Android Development Tools 23.0.0.1245622 (com.android.ide.eclipse.adt.feature.feature.group 23.0.0.1245622)
To: com.android.ide.eclipse.adt.package [23.0.0.1245622]
Cannot satisfy dependency:
From: Android Development Tools 22.6.3.v201404151837-1123206 (com.android.ide.eclipse.adt.feature.group 22.6.3.v201404151837-1123206)
To: com.android.ide.eclipse.adt.package [22.6.3.v201404151837-1123206]
Cannot satisfy dependency:
From: ADT Package 22.2.1.v201309180102-833290 (com.android.ide.eclipse.adt.package.feature.group 22.2.1.v201309180102-833290)
To: com.android.ide.eclipse.adt.feature.group 22.2.0
Cannot satisfy dependency:
From: Android Developer Tools 22.2.1.v201309180102-833290 (com.android.ide.eclipse.adt.package.product 22.2.1.v201309180102-833290)
To: com.android.ide.eclipse.adt.package.feature.group [22.2.1.v201309180102-833290]
After download of the last ADT from the web site, it seems there's another problem.
With SDK Tools rev. 23 proguard is not installed, the folder SDK dir/tools/proguard is missing, and other tools are missing. This version contains several bugs.
Google has released ADT v23.0.2. This solved many problems of previous ADT version 23.
Step-by-step:
Menu Help → Install New Software...
For "Work with", select the Android source https://dl-ssl.google.com/android/eclipse
Tick ADT v23.0 for installation, then click "Next"
Eclipse will show "Install Remediation Page" since there is conflict with previous version. (If it does not, see below.) Select "Update my installation to be compatible with items being installed" to uninstall the old version and install the new one. After that, proceed with the usual steps.
Note: When I installed the new version of ADT, I didn't include the new version of "Android Native Development Tools" package. Instead, I installed the rest of packages first, and then installed "Android Native Development Tools". For a reason, if I try to install all the new packages including "Android Native Development Tools", the installation fails.
If there is no "Remediation page", the only way to remove the ADT plugin from Eclipse is to go to menu Help → About Eclipse → Installation Details and uninstall from there. But there is a risk of uninstalling Eclipse itself.
Google response:
This is a packaging bug. The entire proguard file is missing. We'll have an update asap, but until then just copy it over from a previous version of the tools:
http://dl.google.com/android/android-sdk_r22.6.2-linux.tgz
http://dl.google.com/android/android-sdk_r22.6.2-windows.zip
http://dl.google.com/android/android-sdk_r22.6.2-macosx.zip
and copy over the following files:
tools/hprof-conv
tools/support/annotations.jar
tools/proguard
So at the end if you started from a new ADT copy by hand the files :)
Edit: with the latest ADT release, the bundle should now work with auto-update, so install these new versions:
linux 64 bit vm: http://dl.google.com/android/adt/adt-bundle-linux-x86_64-20140702.zip
linux 32 bit vm: http://dl.google.com/android/adt/adt-bundle-linux-x86-20140702.zip
mac: http://dl.google.com/android/adt/adt-bundle-mac-x86_64-20140702.zip
win32: http://dl.google.com/android/adt/adt-bundle-windows-x86-20140702.zip
win64: http://dl.google.com/android/adt/adt-bundle-windows-x86_64-20140702.zip
Don't try to upgrade from previous version because it doesn’t work at all.
If you have got problems with zipalign, it's now under build-tools and no more under tools/ so you can do a symbolic link or just copy it into the expected folder.
None of the other answers worked for me using the ADT bundle published on developer.android.com.
I ended up downloading the latest version of Eclipse (not the ADT bundle) and then installing the ADT plugin via menu Help → Install new software → entering https://dl-ssl.google.com/android/eclipse (mentioned by #RED_).
I also had to update my workspace to point to my previous workspace, and most things seemed to be restored.
On a side note: This seems like a good time to migrate to Android Studio...
NOTE: Use this approach with caution because this might break your Eclipse installation (see comments).
This might help you if you installed the ADT plugin manually. But if you are using the version of Eclipse from the Eclipse ADT Bundle the below steps could break your Eclipse installation, and you may not be able to use Eclipse again!
Go to
Menu Help → About Eclipse SDK → Installation Details.
Now you will see all 22.0 versions and then click Uninstall button at bottom.
After uninstallation goto:
Menu Help → Install New Software → enter http://dl-ssl.google.com/android/eclipse/
Then install all the things, and now it is ready.
I was updating my build server today and came across the same issue. It has been reported here:
https://code.google.com/p/android/issues/detail?id=72419
The fix is in progress and the work around according to the project manager is:
Please wait for an updated version within a day or two. Until then, your workaround is to do download one of
http://dl.google.com/android/android-sdk_r22.6.2-linux.tgz
http://dl.google.com/android/android-sdk_r22.6.2-windows.zip
http://dl.google.com/android/android-sdk_r22.6.2-macosx.zip
and copy over the following files:
tools/hprof-conv
tools/support/annotations.jar
tools/proguard
[edit]
zipalign was missing for me too, check to see if you need to copy this as well
It works for me :)
If for some reason you installed an ADT preview and need to revert back to the current stable, you can't use the dialog to install "new" software since what you want is actually an older one. Instead do this:
Open Help > About Eclipse... on Windows or Linux. On Mac, use the app's menu > About...
Click the "Installation Details" button.
Select the "Installation History" tab.
Select one of the previous configurations.
Click the "Revert" button at the bottom.
is what they are saying about this:
OK, guys, sorry about all this trouble, and we apologize for the messed up releases. Here's the summary:
There is no way to update an existing ADT bundle that you might have downloaded.
You can do one of two options:
Install Eclipse from eclipse.org and install ADT by pointing to the update site: https://dl-ssl.google.com/android/eclipse
Download bundles from here:
Linux 64-bit VM: http://dl.google.com/android/adt/adt-bundle-linux-x86_64-20140702.zip
Linux 32-bit VM: http://dl.google.com/android/adt/adt-bundle-linux-x86-20140702.zip
Mac: http://dl.google.com/android/adt/adt-bundle-mac-x86_64-20140702.zip
Windows 32-bit: http://dl.google.com/android/adt/adt-bundle-windows-x86-20140702.zip
Windows 64-bit: http://dl.google.com/android/adt/adt-bundle-windows-x86_64-20140702.zip
Starting with ADT bundle 23.0.2, you should be able to update to future versions of ADT.
Source: https://code.google.com/p/android/issues/detail?id=72912
I have done following to resolve an issue.
Go to http://developer.android.com/sdk/installing/installing-adt.html and download the latest ADT ZIP file (at the bottom of page).
Go to Eclipse → menu Help → About Eclipse → Installation details
Delete Android DDM, Android Development Tools, Hierarchy Viewer, Native Development Tools, TraceView, etc., 22.X version.
Menu Help* → Install New Software → Add → Archive → *Select the downloaded ZIP file in step 1.
Select all the latest version of all 23 which I have deleted in step 3 and accept the license agreement.
Restart Eclipse, and it fixes my issue.
Only helped:
Fresh Eclipse installation (http://www.eclipse.org/downloads/packages/eclipse-ide-java-developers/lunar)
Help --> Install New Software --> https://dl-ssl.google.com/android/eclipse/
If you install a new Eclipse version it will work.
Here's what I did:
Installed the new Eclipse version, Luna
Made a backup of the current workspace.
Ran the new Eclipse, Luna, and updated the workspace
Installed the ADT plugin (Help -> Install New Software)
Restarted Eclipse
Done
There is a lot of confusion going around in this thread. There are two solutions depending on how you installed ADT.
If you installed the ADT plugin manually then I believe you can use the "Delete ADT" -> "Install New Software" approach.
If you are using the ADT Bundle then do not follow that solution! You will break Eclipse. Here is an update from a Google member - read #18:
https://code.google.com/p/android/issues/detail?id=72912
You must download a new version of the ADT-Bundle (yep, it's frustrating!).
Just uninstall the previous ADT.
Go to menu Help → About Eclipse → Installation Details
Uninstall all plugins which Id start with com.android.ide
Install ADT again from the update site.
DO NOT DO THIS
Warning: Please see the comments below this answer. These steps have had a negative impact for many people.
Click Help / Install new software...
Click on What is "already installed" (as in picture below)
In the new window you can uninstall the old ADT (uninstall Android Development Tools, Android DDMS, Android Hierarchy Viewer, Android TraceView, Android Native Development Tools and Tracer for OpenGL ES)
Restart Eclipse
Then again click on Help / Install New Software
Choose ADT... Install
I hope it helps!
After trying the approaches in other answers without success, I just installed a new bundle from http://developer.android.com/sdk/installing/index.html?pkg=adt and that worked fine.
Do the following:
As you don't want to re-download all the platforms again, copy the existing one from /OLD_ANDROID_SDK_PATH/sdk/platforms to /NEW_ANDROID_SDK_PATH/sdk/platforms.
When opening the new Eclipse from the recent downloaded bundle, make sure you reuse the previous 'workspace' folder. That will ensure that all your previous settings will be remembered.
After opening the new Eclipse on the previous workspace, please check if the used Android SDK is pointing to the new one (Eclipse preferences -> Android). It might be pointing to the old one, as you've reused the previews workspace settings.
With these steps, you should't have to reconfigure everything, and you won't need to spend time troubleshooting this BUG on this upgrade from Google Developers.
Good luck! ;-)
You need to uninstall the old version and install 23
uninstall:
Help > about Eclipse SDK > Installation Details
select Android related packages to uninstall
And then install V23.
There is no way to update an existing ADT bundle that you might have downloaded.
You can do one of two options:
Install Eclipse from eclipse.org and install ADT by pointing to the update site: https://dl-ssl.google.com/android/eclipse
Download bundles from:
Linux 64 bit VM: http://dl.google.com/android/adt/adt-bundle-linux-x86_64-20140702.zip
Linux 32 bit VM: http://dl.google.com/android/adt/adt-bundle-linux-x86-20140702.zip
Mac: http://dl.google.com/android/adt/adt-bundle-mac-x86_64-20140702.zip
Windows 32 bit: http://dl.google.com/android/adt/adt-bundle-windows-x86-20140702.zip
Windows 64 bit: http://dl.google.com/android/adt/adt-bundle-windows-x86_64-20140702.zip
Starting with ADT bundle 23.0.2, you should be able to update to future versions of ADT.
I was getting the same "conflicting dependency" error on Mac OS X 10.9.3 and simply upgrading was not an option. What finally worked was downloading the latest Eclipse ADT bundle zip file from developer.android.com, extracting it and moving only "eclipse" folder to the place where my old eclipse folder was. (extracting the Eclipse ADT bundle zip file will give you "eclipse" and "sdk" folders).
If you decide to go the same route, first make sure you know what your Workspace path is. This can be found in Preferences. Then rename your old "eclipse" directory (not Eclipse.app) to something like eclipse-22.6.3, then move extracted "eclipse" folder into its place. Run new Eclipse.app inside, and when it asks you about Workspace, just enter the same path as you noted above. Or it can also be set later in Preferences.
Maybe worth adding is that to re-enable Android SDK Manager and Android Virtual Device Manager choose Window -> Customize Perspective -> Command Groups Availability and select Android SDK and AVD Manager. This will add these 2 items to the "Window" menu item for the current perspective (Java).
I didn't move the extracted "sdk" folder, because I already had sdk folder in the same directory as eclipse, which I have already updated to the latest Android tools. But if it makes you feel safer, you can also rename your old sdk folder (for backup purposes) and move the freshly extracted one into its place.
I faced the same problem and solved it. You need to uninstall the Android plugin entirely from within Eclipse (from the "about" section..), including trace view..
Then added the ADT Plugin again (https://dl-ssl.google.com/android/eclipse/) and install it.
The problem is solved!
I guess it's a bug with the SDK manager or ADT Plugin update mechanism...
How to update from 22.xx.x to 23.0.2 (my solution). This will beat the dependency issues.
I was suffering from this issue for days, and I have tried every single solution on this link, but no luck. I finally figured out a solution that actually works!
Please note that this solution works in Windows 7 (64 bit). It should probably work for other Windows operating systems.
Here we go:
download the latest ADT bundle from
http://developer.android.com/sdk/index.html#download
unzip it and open "eclipse" folder --> "plugins" folder
Now go to your old eclipse and open "eclipse" folder --> "plugins" folder, and copy everything inside.
Now paste them into the "plugins" folder of the (NEW ECLIPSE), but DO NOT overwrite anything.
While inside of the "plugins" folder of your new Eclipse, do the search. Type in 22. (notice 22 with a dot) and hit enter.
The search result will show up all the files or folders with .....22.6...... For example,
com.android.ide.eclipse.adt_**22.6.2**.v201403212031-1085508
Highlight all of these files/folders and hit delete key.
Make sure to update your old API/SDK to the latest version and load this sdk directory to work with your new eclipse.
or
You can watch this video, which shows you how to move all your SDK/API to your new SDK folder.
Link: https://www.youtube.com/watch?v=jPZpJdnbbN0
I have not tried to update from any other ADT versions, but I think it should work for any old ADT versions too.
Don't forget to backup stuff before attempting.
What I have just found is that you need to update your ADT plugin in your Eclipse (whether stand alone or ADT Bundle) before updating your build tool.
If your Eclipse installation points to the most recent Build Tool and your Eclipse is having ADT 22.x, it will show those errors.
What worked for me: (on Ubuntu 14.04 64-bit)
Installed an older version of Eclipse and ADT (from the Bundle)
This copy of Eclipse was pointing to an older SDK verion with old build tools (before 20)
Updated the ADT to v23 (via archive, in my case)
Pointed Eclipse to the latest version of build tools.
You may not have an older copy of Eclipse and Build tools, in that case you can uninstall latest build tool from SDK Manager and install the older copy.
Once everything starts working fine, do the above steps.
I am trying to upload older copies of such bundles somewhere on the Internet, will update the links here, once I am done uploading.
I found these instructions in a comment.
Download the newest version of ADT and use your existing workspace. This is actually the least pain-full upgrade you'll ever do. It didn't mess with the .android folder so I still had my original debug key. Only things missing were a couple of add ons I hardly ever use and they are easily installed into the new version.
Note don't install into your existing adt folder create a new folder so you can still fall back if the new install doesn't work.
On ADT-bundled Eclipse I had to first uninstall the ADT and then do a fresh install.
To remove the ADT plugin from Eclipse:
Go to menu Help → About Eclipse → Installation Details.
Select ADT plug-in, then click Uninstall.
After uninstallation install ADT from Help → Install new software.
For me it helped to delete Android 4.4W which is also API 20 and might be a cause for the conflict. So only install Android 4.4W or Android L until they fix it.
And (again this might only be for me) it only works in Android Studio not in Eclipse ...
I had to delete ADT and install it again.
However be warned, this caused me and one other person to have an annotations.jar missing errors in the Java Build path for certain projects, probably because it was trying to look for an old SDK, so upgrading projects is the next step I have to take.
The errors relate to libraries mostly, Google Play Services, Facebook SDK, ActionBarCompat.
For this step, you uninstall ADT, then put the URL back in to download them. The url is: https://dl-ssl.google.com/android/eclipse
I found a solution for the problem with "conflicting dependency". I don't have the same page of Daniel Díaz's response, but a page show "conflicting dependency", and I can't make anything.
The problem is that I'm not the owner of the file. Eclipse was installed in other session (on OS X). I have the right to read and write the Eclipse file, but I'm not the owner. Make a "chown" command on all Eclipse files to solve the problem. After, I have the same result as Daniel Diaz.
I hope this helps someone.
WARNING
There is now an update for ADT 23.0.1, but the Windows and Linux scripts are messed up, so wait with the upgrade!
You could check for example tools/proguard/bin/*.sh in http://dl.google.com/android/android-sdk_r23.0.1-windows.zip.
I did this to solve the same issue (in OS X):
Help > Install New Software > Add or select this repository "http://download.eclipse.org/eclipse/updates/4.3"
Under "Eclipse platform" select the newest version of Eclipse.
The installer will ask if you want to uninstall the ADT, click finish.
Restart Eclipse and install ONLY the ADT 23 using this repository: https://dl-ssl.google.com/android/eclipse.
Restart Eclipse and install DDMS, Hierarchy Viewer, Trace View etc.
Restart Eclipse again.
Hope it helps.
If Eclipse gives an error after uninstalling the ADT plugin from your Eclipse installation, try to edit file config.ini in the Eclipse folder → configuration. Find:
eclipse.application=
And change it to:
eclipse.application=org.eclipse.ui.ide.workbench
I hope it works for you too.
I simply went to my Android resources folder on my C:/ drive (C:/Android), deleted the 'eclipse' folder and all its contents. I downloaded Android Developer Tools once more and just moved over the 'eclipse' folder.
I started up and everything was fine; I had updated to version 23.
Hopefully this helps, possibly not suitable for everyone as some of you have Eclipse modifications but for someone who, like me, wanted a quick fix and get back to developing this seemed to be the easiest path.
I am using Eclipse v4.3 (Kepler), and this is how I solved my problem.
Goto menu Help → Install new software → click Add.
In the popup, give any name (I named it as Eclipse ADT Plugin), and in the link's place, use https://dl-ssl.google.com/android/eclipse/
Once you click OK, you will be displayed with new packages that will be installed and old packages that will be deleted. Don't worry about these packages. Click OK.
New packages will be installed, and this should solve your problem.

Install Eclipse without any Features

The standard/class edition of eclipse still includes JDT, CVS, GIT and various other features.
Is there a way to install it with only 'resource' management/project tools.
Essentially a version of eclipse built without any language or environment in mind.
A lot like an operating system without any programs installed other than what it needs to run itself and provide the means to install programs entirely at the user's discretion.
Post Answer:
http://download.eclipse.org/eclipse/downloads/drops4/R-4.3-201306052000/
The eclipse-platform section contains no-frills, just raw eclipse.
try this link (http://www.eclipse.org/downloads/moreinfo/custom.php) It should contain what is called a Eclipse Platform Runtime Binaries which is the most minimalist package available.
Same answer I wrote in: Eclipse without plugins for windows
You can download it from here: http://download.eclipse.org/eclipse/downloads/index.html. There you can find 'clean' builds of Eclipse, which do not ship with common development tools.
You still can uninstall the plugins you don't want this way :
Menu > Help > About eclipse SDK > Installation details
Install software tab
Select the plugin you don't want
Uninstall button
Goto https://download.eclipse.org/eclipse/downloads/
Choose a release
e.g. "Latest Release : 4.10" --> https://download.eclipse.org/eclipse/downloads/drops4/R-4.10-201812060815/
On this new page choose "Platform Runtime Binary"
It contains the Eclipse Rich Client Platform base bundles and do not contain source or programmer documentation.

Eclipse EGit and GWT/GAE

I have a central GIT repository, so that i can work on the project from different computers.
However when i pull the project on the other computer i get the error "Unbound classpath container: 'GWT SDK [missing]' in project 'Test Project'" (I also get a similar error for GAE).
So my question is: How do i setup my project so the same version of GAE/GWT is used on all computers.
I suspect the problem could be caused by the different versions of GAE and GWT on the machines. For example: GWT (1) is not the same version on the machines as it depends on when you updated GWT.
I ran into this problem too, and solved it by installing the GAE and GWT sdks under specific names, manually. That is, instead of relying on eclipse's software update tools, I downloaded the specific SDK version I wanted from the googlecode sites, and then added them manually to eclipse. This way their names include the numbers, and your git repository can store information about which versions it's using.
I do have to install the sdks manually on each developer machine, which is a drag.
To install an sdk manually:
Download it
Right-click on the sdk container in eclipse (in project explorer, it probably says GWT SDK [missing])
Choose properties
Click configure SDKs
follow the path to install a new sdk
You don't have to set the new sdk as default or anything - your project will pick it up immediately after you install it.
Note to any GPE developers: it'd be nice if the sdks were installed automatically with a version-specific name for the benefit of source control!
You can Change the project's SDK target.
In eclipse go to Marker [it is a tab next on the extreme left of the tabs including Console and Development] --> Left Click problem indication --> Click Quick fixes and choose the option which re-configures the project. This should fix the problem. Note that if your code uses features that changed between SDK versions you will have to make changes.
Combined with Rilev Lark's answer This is a chance to Update your projects or your environments whenever the problem occurs.