I’ve encountered this problem far too frequently since i switched over to Android Studio. This is indeed an issue with the repository not being accessible – either due to a network issue or, more likely, the repo being down for whatever reason.
The simplest work-around that I’ve found is to just select the “work offline” mode within the Android Studio preferences. This doesn’t help if you need to add a new dependency, but if you already have all your dependencies added it does the trick.
To enable this setting go to:
Preferences -> Gradle
In the right side options go down to “Global Gradel Settings” and check the “Offline work” box.
The box should look like:
You can periodically uncheck this box to see if the repo is back online.
NOTE: This option is the equivalent of setting the –offline flag when running a gradle build from the command line.