Upon reopening Android Studio after an improper shutdown, my gradle project sync failed and many errors like: "Failed to resolve: junit:junit:4.12" started showing up in the Event Log. Screenshot is given below.
I tried the following things to no avail:
- Updated Android Studio to ver 2.3.1 and thus also the Gradle
- I also had error for "Plugin Error: required plugin "xyz" is disabled" so i deselected all the plugins showing errors from settings and reselected them which removed the error.
- Then i went to Files -> Invalidate caches/restart
What should i do?
UPDATE: After clicking on "Disable offline mode and sync project", this is what happened.
From your first screenshot
Gradle is in offline mode, which means that it won't go to the network to resolve dependencies.
Go to Preferences > Gradle and uncheck "Offline work".
After that try cleaning the project and Re-running again?
Here is a working solution..
Step 1) In Android Studio go to File > Project Structure
there unticheck "Use Embedded JDK" and below choose your JDK location..
Step 2)
Go to file gradle > wrapper > gradle-wrapper-proparties change gradle version to 3.5-all
Step 3) close the project and reopen
What worked for me;
Go to Preferences > Gradle & uncheck "Offline work"
Goto File > Invalidate caches and restart.
The project would restart and can begin to install dependencies. Dont worry if it takes a time, that could be due to slow network. Just go and sip coffee while you wait ;)
来源：https://stackoverflow.com/questions/43447360/gradle-project-sync-failed-in-android-studio-2-3-1