问题
I just updated my Android Studio to the current 0.3.1 version. Consequently I've started getting a few issues that I can't seem to understand. First I get this message about problems with the plugin on launching Android Studio. The message is as follows:
Plugin Error
Problems found loading plugins: Plugin "Android Designer" was not loaded:
required plugin "Android Support" is disabled.
Plugin "Google Cloud Tools For Android Studio" was not loaded:
required plugin "Android Support" is disabled.
Disable not loaded plugins Enable Android Support Open plugin manager
The most worrying - which has essentially halted my progress at the moment - is that the IDE can't resolve XML files in the R.xxx. Such as this line:
setContentView(R.layout.activity_lists);
It suggests I use android.R which brings up further errors due to incompatibility. I'm not sure how to fix this. On another occassion when this happened, further updates automatically resolved this issue.
回答1:
In Android SDK Manager, select the following items and then click Install packages:
Extras/Google Repository
Extras/Android Support Repository
After install restart Android studio
回答2:
I try to remove and reinstall Extras but the problem is not solved , I find a solution to correct that to reset AndoidStudio.
You have to remove this directory and restart AndroidStudio to detect the SDK location
~/Library/Preferences/AndroidStudio*
~/Library/Caches/AndroidStudio*
~/Library/Logs/AndroidStudio*
来源：https://stackoverflow.com/questions/19681234/android-studio-updates-have-led-to-errors