I am currently trying to compile and test a small Android Application.
I am using Eclipse, and have SDK 4.2 (Api Level 17) installed. I've set
<uses-sdk android:targetSdkVersion="17" android:minSdkVersion="8" />
although I've tried also different values (i.e. 17/17).
I do not use any GoogleAPI functions, nor do I use functions that are not available in API Level 8. Or at least I do not get any compile errors or warnings in that regard.
When I compile the project and run it on a real device running Android 2.2.1 the Application runs fine. However when I try to run the application on an emulator (Android Virtual Device) with Android 4.2, Api Level 17 I get the following error:
[2012-12-10 21:10:29 - SoftKeyboard] Installation error: INSTALL_FAILED_VERSION_DOWNGRADE
[2012-12-10 21:10:29 - SoftKeyboard] Please check logcat output for more details.
[2012-12-10 21:10:29 - SoftKeyboard] Launch canceled!
Logcat however is empty. I have really no clue, what this error even means...
It means you're trying to install an app with the same packageName as an app that's already installed on the emulator, but the one you're trying to install has a lower versionCode (integer value for your version number).
You might have installed from a separate copy of the code where the version number was higher than the copy you're working with right now. In either case, either:
uninstall the currently installed copy
or open up your phone's Settings > Application Manager to determine the version number for the installed app, and increment your <manifest android:versionCode to be higher in the AndroidManifest.